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The Astrometric Performance of the China Space Station Telescope(CSST)Sky Survey in Extending the Gaia Celestial Reference Frame

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Research in Astronomy and Astrophysics 2024年第8期24卷 133-140页

作者： Jun Yao jia-Cheng liu Niu liu zi Zhu Zhen-wei Wang School of Astronomy and Space Science Key Laboratory of Modern Astronomy and Astrophysics(Ministry of Education)Nanjing UniversityNanjing 210023China University of Chinese Academy of Sciences Nanjing 211135China

The multi-color imaging sky survey conducted by the China Space Station Telescope(CSST)holds significant promise for advancing the development of the celestial reference *** this study,we focus on assessing the astrometric performance of the CSST celestial reference frame(CSST-CRF)in extending the Gaia Celestial Reference Frame 3(Gaia-CRF3).First,the orientation precision of the CSST reference frame is evaluated using a simulated set of extragalactic sources with CSST g magnitudes ranging from 18 to 25 *** estimated orientation uncertainty caused by random error insignificantly affects the alignment between Gaia-CRF3 and the ***,the systematic effect of incomplete CSST sky coverage on the alignment between CSST-CRF and Gaia-CRF3 is discussed by analyzing the differences between the subset of Gaia-CRF3 in the CSST observation region(Gaia-CRF3′)and Gaia-CRF3 as a *** the third International Celestial Reference Frame(ICRF3)S/X band as an intermediate reference frame,the orientation offset between Gaia-CRF3′and GaiaCRF3 is estimated to be 20μ*** offset is marginally larger than the orientation offset between Gaia-CRF3 and the ICRF3,approximately 15μ*** residual spin and glide rate of Gaia-CRF3′are derived from the proper motions,consistent with that of Gaia-CRF3 within the formal ***,we explore the role of CSST in establishing a multi-band celestial reference frame by comparing its limiting magnitude and observation accuracy with existing catalogs in the infrared and ultraviolet *** to its broad wavelength coverage and highprecision measurements,CSST is well-positioned to make significant contributions to the development of a multiband celestial reference frame.

关键词： astrometry-reference systems-surveys

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SnO_(2)/metal organic complex composite derived from low-temperature activated metal organic complex for advanced lithium storage

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Rare Metals 2024年第7期43卷 3032-3043页

作者： gui-Long liu zi-Han Zhao Jin-Ke Shen zi-Bo Zhao Nai-Teng Wu Dong-Lei guo wei-wei Yuan Yong liu Ye-Hua Su Xian-Ming liu Luoyang Key Laboratory of Green Energy Materials College of Chemistry and Chemical EngineeringLuoyang Normal UniversityLuoyang 471934China School of Materials Science and Engineering Henan University of Science and TechnologyLuoyang 471023China Inner Mongolia Shijie Chemical Co. Ltd.Alxa League 737300

Sn-based metal organic complexes with coordination bonds,multi-active sites,and high theoretical capacity have attracted much attention as promising anodes for lithium ion ***,the low electrical conductivity and huge volume changes restricted their electrochemical stability and practical ***,Snbased anode with superior electrochemical performance,including a high reversible capacity of 1050.1 mAh·g^(-1)at 2 A·g^(-1)and a stable capacity of 1105.5 mAh·g^(-1)after 500 cycles at 1 A·g^(-1),was fabricated via a low-temperature calcination strategy from Sn metal organic *** low-temperature calcination process regulates Sn-O bond and prevents the agglomeration of SnO_(2),generating highly dispersed SnO_(2) decorated metal organic complexes and providing sufficient active sites for ion *** situ characterizations expound that the undecomposed Sn-based metal organic complexes could be transformed into SnO_(2) during lithiation and delithiation,which enhances the electrical conductivity and induces a strong pseudo-capacitive behavior,accelerating the electrochemical kinetics;the multiple solid electrolyte interface with inflexible LiF and flexible ROCO_(2)Li buffers the volume variation of the electrode,resulting in its high electrochemical *** work provides a simple strategy for preparing excellent Sn-based anodes from metal organic complexes and reveals the lithium storage mechanism of the prepared Snbased anode.

关键词： Metal organic complex Lithium ion battery Electrochemical activation Low-temperature activation Partial decomposition

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Dynamical switchable quantum nonreciprocity induced by off-resonant chiral two-photon driving

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Science China(Physics,Mechanics & Astronomy) 2024年第6期67卷 31-37页

作者： Da-wei liu zi-Hao Li Shi-Lei Chao Ying Wu liu-Gang Si School of Physics and Institute for Quantum Science and Engineering Huazhong University of Science and TechnologyWuhan 430074China

Optical nonreciprocity,which refers to the direction-dependent emission,scattering and absorption of photons,plays a very important role in quantum engineering and quantum information ***,we propose an all-optical approach to achieve the optical dynamical switchable quantum nonreciprocity by an off-resonant chiral two-photon driving in a single microring cavity,which differs from the conventional nonreciprocal *** is shown that the optical field with time-dependent statistical properties can be generated and the nonreciprocity flips periodically,with switchable photon blockade and photon-induced tunneling *** find that the dynamical system is robust and immune to the parameter variations,which loosens the parameter range of ***,the time window for one-way quantum information is sufficiently wide and *** work opens a new idea for the current quantum nonreciprocal research,which can facilitate a memory functionality and be used for future inmemory superconducting quantum *** other nonreciprocal quantum devices,i.e.,dynamical switchable nonreciprocal squeezing and entanglement,may be inspired by our method,which is expected to have important applications in future quantum technology.

关键词： dynamical switchable nonreciprocity single-photon source chiral two-photon driving

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Tongxinluo Activates PI3K/AKT Signaling Pathway to Inhibit Endothelial Mesenchymal Transition and Attenuate Myocardial Fibrosis after Ischemia-Reperfusion in Mice

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Chinese Journal of Integrative Medicine 2024年第7期30卷 608-615页

作者： wei Ya-ru HOU Yun-long YIN Yu-jie LI Zhen liu Yi HAN Ning-xin WANG zi-xuan liu Lu WANG Xiao-qi HAO Yuan-jie MA Kun gu jiao-jiao jia Zhen-hua Graduate School Hebei University of Chinese MedicineShijiazhuang050090China Shijiazhuang Yiling Pharmaceutical New Drug Evaluation Center Shijiazhuang050035China Hebei Institute of Integrated Traditional and Western Medicine Shijiazhuang050035China National Key Laboratory for Innovation and Transformation of Luobing Theory Shijiazhuang050035China Department of Cardiology Hebei Yiling HospitalShijiazhuang050091China Graduate School Hebei Medical UniversityShijiazhuang050017China

Objective To investigate the potential role of Tongxinluo(TXL)in attenuating myocardial fibrosis after myocardial ischemia-reperfusion injury(MIRI)in *** A MIRI mouse model was established by left anterior descending coronary artery ligation for 45 *** to a random number table,66 mice were randomly divided into 6 groups(n=11 per group):the sham group,the model group,the LY-294002 group,the TXL group,the TXL+LY-294002 group and the benazepril(BNPL)*** day after modeling,TXL and BNPL were administered by *** injection of LY-294002 was performed twice a week for 4 consecutive *** was used to measure cardiac function in *** staining was used to evaluate the degree of myocardial fibrosis in *** and quantitative analysis of endothelial mesenchymal transition(EndMT)after MIRI was performed by immunohistochemistry,immunofluorescence staining and flow cytometry,*** protein expressions of platelet endothelial cell adhesion molecule-1(CD31),α-smoth muscle actin(α-SMA),phosphatidylinositol-3-kinase(PI3K)and phospho protein kinase B(p-AKT)were assessed using Western *** TXL improved cardiac function in MIRI mice,reduced the degree of myocardial fibrosis,increased the expression of CD31 and inhibited the expression ofα-SMA,thus inhibited the occurrence of EndMT(P0.05).In addition,the use of the PI3K/AKT pathway-specific inhibitor LY-294002 to block this pathway and combination with TXL intervention,eliminated the protective effect of TXL,further supporting the protective effect of *** TXL activated the PI3K/AKT signaling pathway to inhibit EndMT and attenuated myocardial fibrosis after MIRI in mice.

关键词： myocardial fibrosis endothelial mesenchymal transition myocardial ischemia-reperfusion injury phosphatidylinositol-3-kinase/protein kinase B(PI3K/AKT)pathway

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Exploring mechanism of hidden,steep obliquely inclined bedding landslides using a 3DEC model:A case study of the Shanyang landslide in Shaanxi Province,China

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China Geology 2024年第2期7卷 303-314,I0001-I0003页

作者： jia-yun Wang zi-long Wu Xiao-ya Shi Long-wei Yang Rui-ping liu Na Lu Xi’an Center of China Geological Survey/Northwest China Center for Geoscience Innovation Xi’an 710119China Xi’an University of Science and Technology Xi’an 710054China Wuhan Design&Research Institute Co. Ltd.of China Coal Technology&Engineering GroupWuhan 430064China

Catastrophic geological disasters frequently occur on slopes with obliquely inclined bedding structures(also referred to as obliquely inclined bedding slopes),where the apparent dip sliding is not readily *** phenomenon has become a focal point in landslide ***,there is a lack of studies on the failure modes and mechanisms of hidden,steep obliquely inclined bedding *** study investigated the Shanyang landslide in Shaanxi Province,*** field investigations,laboratory tests of geotechnical parameters,and the 3DEC software,this study developed a numerical model of the landslide to analyze the failure process of such *** findings indicate that the Shanyang landslide primarily crept along a weak interlayer under the action of *** landslide,initially following a dip angle with the support of a stable inclined rock mass,shifted direction under the influence of argillization in the weak interlayer,moving towards the apparent dip *** slide resistance effect of the karstic dissolution zone was increasingly significant during this process,with lateral friction being the primary resistance force.A reduction in the lateral friction due to karstic dissolution made the apparent dip sliding characteristics of the Shanyang landslide more ***,deformations such as bending and uplift at the slope’s foot suggest that the main slide resistance shifts from lateral friction within the karstic dissolution zone to the slope foot’s resistance force,leading to the eventual buckling failure of the *** study unveils a novel failure mode of apparent dip creep-buckling in the Shanyang landslide,highlighting the critical role of lateral friction from the karstic dissolution zone in its failure *** insights offer a valuable reference for mitigating risks and preventing disasters related to obliquely inclined bedding landslides.

关键词： Landslide Steep obliquely inclined bedding slope Failure mode Failure mechanism Apparent dip creep-buckling Lateral friction 3DEC model Landslide numerical model Geological hazards survey engineering

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Visible-Light-Driven Four-Component Radical Relay Aminocarbonylation of Unactivated Alkenes

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Chinese Journal of Chemistry 2024年第9期42卷 990-996页

作者： Bin Lu Feng-Shuo Bao zi-wei He Wen-Jing Xiao jia-Rong Chen Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction College of ChemistryCentralChina Normal University152 Luoyu RoadWuhanHubei 430079China Wuhan Institute of Photochemistry and Technology 7North Bingang RoadWuhanHubei 430083China Key Laboratory of Organo-Pharmaceutical Chemistry of jiangxi Province Gannan Normal UniversityGanzhouJiangxi 341000China

Catalytic four-component radical carbonylation of unactivated alkenes has recently been recognized as a robust protocol for rapid construction of various structurally diverse carbonyl *** the significance of fluorine-containing groups,this reaction class has been extensively applied to assembly of a variety of perfluoroalkyl carboxylic acid derivatives by transition metal ***,we report a visible-light-driven radical relay 1,2-perfluoroalkylation aminocarbonylation of unactivated alkenes using CO gas as carbonyl source and 4CziPN as organic photocatalyst.A wide range of alkenes and amines were well tolerated,providing the valuableβ-perfluoroalkylated amides with generally good yields and high chemoselectivity.

关键词： Visible light Photoredox catalysis Radical aminocarbonylation Multicomponent reaction Carbon monoxide Unactivated alkenes AmidesIReactionmechanisms

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Micro segment analysis of supercritical methane thermal-hydraulic performance and pseudo-boiling in a PCHE straight channel

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Petroleum Science 2024年第2期21卷 1275-1289页

作者： Qian Li zi-Jie Lin liu Yang Yue Wang Yue Li wei-Hua Cai Laboratory of Thermo-Fluid Science and Nuclear Engineering Northeast Electric Power UniversityJilin132000JilinChina School of Energy and Power Engineering Northeast Electric Power UniversityJilin132000JilinChina

The printed circuit heat exchanger(PCHE) is receiving wide attention as a new kind of compact heat exchanger and is considered as a promising vaporizer in the LNG process. In this paper, a PCHE straight channel in the length of 500 mm is established, with a semicircular cross section in a diameter of 1.2 *** simulation is employed to investigate the flow and heat transfer performance of supercritical methane in the channel. The pseudo-boiling theory is adopted and the liquid-like, two-phase-like, and vapor-like regimes are divided for supercritical methane to analyze the heat transfer and flow *** results are presented in micro segment to show the local convective heat transfer coefficient and pressure drop. It shows that the convective heat transfer coefficient in segments along the channel has a significant peak feature near the pseudo-critical point and a heat transfer deterioration when the average fluid temperature in the segment is higher than the pseudo-critical point. The reason is explained with the generation of vapor-like film near the channel wall that the peak feature related to a nucleateboiling-like state and heat transfer deterioration related to a film-boiling-like state. The effects of parameters, including mass flow rate, pressure, and wall heat flux on flow and heat transfer were *** calculating of the averaged heat transfer coefficient of the whole channel, the traditional method shows significant deviation and the micro segment weighted average method is adopted. The pressure drop can mainly be affected by the mass flux and pressure and little affected by the wall heat flux. The peak of the convective heat transfer coefficient can only form at high mass flux, low wall heat flux, and near critical pressure, in which condition the nucleate-boiling-like state is easier to appear. Moreover,heat transfer deterioration will always appear, since the supercritical flow will finally develop into a filmboiling-like state. So hea

关键词： Printed circuit heat exchanger Vaporization Supercritical methane Pseudo-boiling Micro segment analysis

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Reinfection and Risk Factors of SARS-CoV-2 during an Omicron Wave 2022 in Shanghai

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Biomedical and Environmental Sciences 2024年第2期37卷 204-209页

作者： WANG Pei Qin WANG Xiao Hang WANG jian SHI Zhi Wen chu Dong Mei WANG Zhi Fei ZHANG Mu Bai liu wei ZHOU zi Jie XIE wei Fen Department of Gastroenterology Changzheng HospitalNaval Medical UniversityShanghai 200003China Health examination center Changzheng HospitalNaval Medical UniversityShanghai 200003China

Multiple waves of coronavirus disease 2019(COVID-19) outbreaks have affected numerous countries worldwide. The first case of SARS-CoV-2 reinfection was reported in Hong Kong in August 2020^([1]), leading to increased interest in the effectiveness of natural immunity acquired from primary infection. While data reports vary across countries, all findings indicate that prior SARS-CoV-2 infection provides substantial protection against reinfection^([2]). However, natural immunity from infection with previous non-Omicron or early Omicron sub-lineages offers lower levels of protection against Omicron reinfection, with rates below 60%^([3]) and approximately 75%[4], respectively.

关键词： immunity infection Omi

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Relation Between the Eventual Continuity and the E-property for Markov-Feller Semigroups

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 1-16页

作者： Yong liu zi-yu liu LMAM School of Mathematical SciencePeking UniversityBeijing100871China

We investigate some relations between two kinds of semigroup regularities, namely the e-property and the eventual continuity, both of which contribute to the ergodicity for Markov processes on Polish *** precisely, we prove that for Markov-Feller semigroup in discrete time and stochastically continuous MarkovFeller semigroup in continuous time, if there exists an ergodic measure whose support has a nonempty interior,then the e-property is satisfied on the interior of the support. In particular, it implies that, restricted on the support of each ergodic measure, the e-property and the eventual continuity are equivalent for the discrete-time and the stochastically continuous continuous-time Markov-Feller semigroups.

关键词： Markov-Feller semigroup ergodicity e-property eventual continuity

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Establishment of predictive models and determinants of preoperative gastric retention in endoscopic retrograde cholangiopancreatography

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World Journal of Gastrointestinal Surgery 2024年第8期16卷 2574-2582页

作者： Ying jia Hao-Jun Wu Tang Li jia-Bin liu Ling Fang zi-Ming liu Department of Thyroid Surgery West China HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina Division of Biliary Tract Surgery Department of General SurgeryWest China HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina Division of General Surgery West China Hospital-Chengdu Shangjin NanfuWest China HospitalChengdu 611730Sichuan ProvinceChina

BACKGROUND Study on influencing factors of gastric retention before endoscopic retrograde cholangiopancreatography(ERCP)background:With the wide application of ERCP,the risk of preoperative gastric retention affects the smooth progress of the *** study found that female,biliary and pancreatic malignant tumor,digestive tract obstruction and other factors are closely related to gastric retention,so the establishment of predictive model is very important to reduce the risk of *** A retrospective analysis was conducted on 190 patients admitted to our hospital for ERCP preparation between January 2020 and February *** baseline clinical data were collected using an electronic medical record *** were randomly matched in a 1:4 ratio with data from 190 patients during the same period to establish a validation group(n=38)and a modeling group(n=152).Patients in the modeling group were divided into the gastric retention group(n=52)and non-gastric retention group(n=100)based on whether gastric retention occurred *** data of patients in the validation group and identify factors influencing preoperative gastric retention in ERCP patients.A predictive model for preoperative gastric retention in ERCP patients was constructed,and calibration curves were used for *** receiver operating characteristic(ROC)curve was analyzed to evaluate the predictive value of the *** We found no statistically significant difference in general data between the validation group and modeling group(P>0.05).The comparison of age,body mass index,hypertension,and diabetes between the two groups showed no statistically significant difference(P>0.05).However,we noted statistically significant differences in gender,primary disease,jaundice,opioid use,and gastrointestinal obstruction between the two groups(P<0.05).Mul-tivariate logistic regression analysis showed that gender,primary disease,jaundice,opioid use,and gastrointestina

关键词： Cholangiopancreatography Gastric retention Influencing factors Predictive model Endoscope

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