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Thirty-day Outcomes of First-in-man Implantation of a Novel Transcatheter Edge-to-edge Mitral Repair System in Patients With Severe Mitral Regurgitation

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Cardiology Discovery 2024年第2期4卷 142-147页

作者： Kai Xu Yan Wang Shaoliang Chen Xiangbin Pan Ben He Ruiyan Zhang Bin Wang Junjie Zhang Zhengbin Zhu Bin Wang Da Zhu Yaling Han Department of Cardiology General Hospital of Northern Theater CommandShenyangLiaoning 110016China Department of Cardiology Xiamen Cardiovascular Hospital Xiamen UniversityXiamenFujan 361102China Department of Cardiology Nanjing First HospitalNanjingJiangsu 210006China Department of Structure Heart Disease Fuwai Yunnan Cardiovascular HospitalKunmingYunnan 650102China Department of Cardiology Shanghai Chest HospitalShanghai 200030China Department of Cardiology Rujin Hospital Shanghai Jiaotong University School of MedicineShanghai 200025China

Objectives:The aim of this multicenter,prospective,single-arm pilot study(*** number:NCT05040074)was to observe the procedural and 30-day results of the novel transcatheter mitral valve repair system,SQ-Kyrin■-M Clip(Shenqi Medical,Shanghai,China),in patients with severe mitral regurgitation(MR).Methods:The heart team considered patients from 5 centers in China with clinically significant functional mitral regurgitation≥3+despite optimal medical therapy or degenerative mitral regurgitation≥3+with high surgical risk as candidates for transcatheter *** patients received transcatheter edge-to-edge mitral valve repair under general *** primary outcome was technical success,which included all of the following measured at the exit from the catheterization laboratory:(1)absence of procedural mortality;(2)successful access,delivery,and retrieval of the device delivery system;(3)successful deployment and correct positioning of the frst intended device;and(4)no emergency surgery or reintervention related to the device or access *** secondary outcomes included all-cause mortality,serious adverse events,device success,and procedural success 30 d after the ***:From June 2021 to December 2021,18 patients were enrolled in this study with age(75.7±7.4)*** patients had MR 4+,while 3 had MR 3+.Technical success was achieved in all patients,including 6 degenerative mitral regurgitation and 12 functional mitral regurgitation *** was no all-cause mortality at 30 *** patient had single leaflet device attachment within 30 d,which was regarded as a serious adverse event,and the patient was successfully treated with reintervention by implanting another *** patient's transmitral gradient was 6 mmHg(>5 mmHg),with an effective orifice area of 2.57 cm^(2) after the *** patients had device success and procedural success at 30 d *** patients had MR 1+,3 had MR 2+,and only 1

关键词： Heart failure Mitral regurgitation Transcatheter mitral valve repair Transcatheter edge-to-edge repair

Stable hydrogen isoscape in precipitation generated using data fusion for East China

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Science China Earth Sciences 2024年第9期67卷 2972-2988页

作者： Jiacheng CHEN Jie CHEN Xunchang John ZHANG Peiyi PENG State Key Laboratory of Water Resources Engineering and Management Wuhan University Hubei Key Laboratory of Water System Science for Sponge City Construction Wuhan University USDA-ARS Oklahoma and Central Plains Agricultural Research Center Southwest Research Institute for Hydraulic and Water Transport Engineering Chongqing Jiaotong University

The stable hydrogen isotope in precipitation is an effective environmental tracer for climatic and hydrologic ***, accurate and high-precision precipitation hydrogen isoscapes are currently unavailable in China. In this study, a data fusion method based on Convolutional Neural Networks（CNN） is used to fuse the hydrogen isotopic composition（δ2Hp） of observations and isotope-equipped general circulation model（iGCM） simulations. A precipitation hydrogen isoscape with a temporal resolution of monthly and a spatial resolution of 50–60 km is established for East China for the 1969–2017 period. Prior to building the isoscape, the performance of three data fusion methods（DFMs） and two bias correction methods（BCMs） is compared. The results indicate that the CNN fusion method performs the best with a correlation coefficient larger than 0.90 and root mean square error smaller than 10.5‰ when using observation as a benchmark. The fusion methods based on back propagation and long short-term memory neural network perform similarly, while slightly outperforming the bias correction methods. Thus, the CNN method is used to generate the hydrogen isoscape, and the temporal and spatial distribution characteristics of the hydrogen isotope in precipitation are analyzed based on this dataset. The generated isoscape shows similar spatial and temporal distribution characteristics to observations. In general, the distribution pattern of δ2Hpis consistent with the temperature effect in northern China, and consistent with the precipitation amount effect in southern China. The trend of the δ2Hptime series is consistent with that of observed precipitation and temperature. Overall, the generated isoscape effectively reproduces the observations, and has the characteristics of time continuity and relative spatial regularity, which can provide valuable data support for tracking atmospheric and hydrological processes.

关键词： Precipitation Precipitation isotope General circulation model Data fusion Dataset

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Machine learning noise exposure detection of rail transit drivers using heart rate variability

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Transportation Safety and Environment 2024年第2期6卷 122-132页

作者： Zhiqiang Sun Haiyue Liu Yubo Jiao Chenyang Zhang Fang Xu Chaozhe Jiang Xiaozhuo Yu Gang Wu School of Transportation and Logistics Southwest Jiaotong UniversityChengdu 611756China Lanzhou Rail Transit Co. Ltd.Lanzhou 730000China Sichuan Tourism university Chengdu 610100China PagerDuty Inc.905 King StWTorontoON M6K 3G9Canada

Previous studies have found that drivers’physiological conditions can deteriorate under noise conditions,which poses a potential hazard when *** a result,it is crucial to identify the status of drivers when exposed to different ***,such explo-rations are rarely discussed with short-term physiological indicators,especially for rail transit *** this study,an experiment involving 42 railway transit drivers was conducted with a driving simulator to assess the impact of noise on drivers’physiological *** the individuals’heterogeneity,this study introduced drivers’noise annoyance to measure their *** variances of drivers’heart rate variability(HRV)along with different noise adaptions are explored when exposed to different noise *** machine learning approaches(support vector machine,K-nearest neighbour and random forest)were then used to classify their physiological status under different noise conditions according to the HRV and drivers’self-noise *** indicate that the volume of traffic noise negatively affects drivers’performance in their *** with different noise adaptions but exposed to a fixed noise were found with discrepant HRV,demonstrating that noise adaption is highly associated with drivers’physiological status under *** is also found that noise adaption inclusion could raise the accuracy of ***,the random forests classifier performed the best in identifying the physiological status when exposed to noise conditions for drivers with different noise adaptions.

关键词： noise exposure detection noise adaption heart rate variability(HRV) machining learning simulator experiment

Mechanism of SrS∶Ce Thin Film Electroluminescence

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Journal of Rare Earths 1999年第2期17卷 25-28页

作者： Xu, Zheng Xu, Chunxiang Lou, Zhidong Xu, Xurong northern jiaotong univ Beijing China

The influence of the delocalization probability on the mixing interaction between excited levels of Ce3+ and the conduction band of SrS was analysed. The observation of emission wave forms of SrSCe thin film electroluminescence showed that only leading edge emission peak was observed for one sample and the leading and trailing edge emission peaks were observed for another in a half period of sinusoid applied voltage. This difference is related to the influences of sulphur vacancies on the excitation and emission processes. The leading edge emssion is dominated by discrete luminescence caused by direct impact excitation and the trailing edge emission and a part of leading edge emission belong to recombination luminescence caused by impact ionization and delocalization.

关键词： Rare earths Cerium Strontium sulphide Thin film Electroluminescence mechanism

Study on Method of Comprehensive Evaluating for Information System Projects

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Journal of Systems Engineering and Electronics 2000年第2期11卷 17-24页

作者： Xu, Weixiang Zhang, Quanshou northern jiaotong univ Beijing China

In this paper, a new method of evaluation for information system project is proposed on the basis of the meta-synthesis methodology from qualitative analysis to quantitative analysis. DHGF is an integrated method of improved Delphi, analytic hierarchy process, grey interconnect degree and fuzzy comprehensive evaluating. It gives full play to their advantages and controls theirs disadvantages. The feasibility and effectiveness of DHGF are shown in the practical example.

关键词： Computer systems programming Fuzzy sets Mathematical models Response time (computer systems)

Interpreting Larix principis-rupprechtii radial growth in northern China based on the Vaganov-Shashkin model

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Journal of Forestry Research 2024年第3期35卷 99-110页

作者： Jiachuan Wang Shuheng Li Qiang Li Yili Guo Yijie Han Qi Liu Yiqi Zhao College of Urban and Environmental Sciences Northwest UniversityXi'an 710127People's Republic of China Institute of Global Environmental Change Xi'an Jiaotong UniversityXi'an 710049People's Republic of China Shaanxi Key Laboratory of Earth Surface System and Environmental Carrying Capacity Northwest UniversityXi'an 710127People's Republic of China State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi'an 710061People's Republic of China

Changes in annual radial growth is an important indication of climate change. Dendroclimatology studies in northern China have focused on linear statistical analysis,but lacking studies based on the process of ring formation to clarify the radial growth of trees. Tree-ring width standard chronology(STD) was established using samples of Larix principis-rupprechtii collected at 2303 m altitude on Luya Mountain. Using the Vaganov-Shashkin(VS) model to simulate growth and development, the internal physiological mechanism of radial growth is identified. It was concluded that:(1) the growing season of L. principis-rupprechtii was May to September;(2) soil moisture was a significant factor in the early and late growing seasons, and temperature was the dominant factor in its main growth period;and(3) formation of narrow ring widths was closely related to drought stress, the development of wide ring widths will be restricted by increasing future temperatures. The VS model is applicable for radial growth simulation of subalpine coniferous forests and for guiding the cultivation of local tree species in the future.

关键词： Vaganov-Shashkin model Larix principis-rupprechti Tree-ring width Annual growth

Large contributions of emission reductions and meteorological conditions to the abatement of PM_(2.5)in Beijing during the 24th Winter Olympic Games in 2022

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Journal of Environmental Sciences 2024年第2期136卷 172-188页

作者： Yaping Jiang Shaocai Yu Xue Chen Yibo Zhang Mengying Li Zhen Li Zhe Song Pengfei Li Xiaoye Zhang Eric Lichtfouse Daniel Rosenfeld Key Laboratory of Environmental Remediation and Ecological Health Ministry of EducationResearch Center for Air Pollution and HealthCollege of Environmental and Resource SciencesZhejiang UniversityHangzhou 310058China College of Science and Technology Hebei Agricultural UniversityBaoding 071000China Chinese Academy of Meteorological Sciences China Meteorological AdministrationBeijing 100081China Aix-Marseille univ CNRSColl FranceCNRSIRDINRAEEuropole Mediterraneen de l’ArboisAvenue Louis Philibert13100 Aix en ProvenceFrance Xi’an jiaotong university State Key Laboratory of Multiphase Flow in Power EngineeringXi’an 710049China Institute of Earth Sciences The Hebrew University of JerusalemJerusalemIsrael

To guarantee the blue skies for the 2022 Winter Olympics held in Beijing and Zhangjiakou from February 4 to 20,Beijing and its surrounding areas adopted a series of emission control *** provides an opportunity to determine the impacts of large-scale temporary control measures on the air quality in Beijing during this special ***,we applied the WRF-CMAQ model to quantify the contributions of emission reduction measures and meteorological *** show that meteorological conditions in 2022 decreased PM_(2.5)in Beijing by 6.9 and 11.8μg/m^(3)relative to 2021 under the scenarios with and without emission reductions,*** emission reduction measures implemented in Beijing and seven neighboring provinces resulted in an average decrease of 13.0μg/m^(3)(-41.2%)in PM_(2.5)in *** the entire period,local emission reductions contributed more to good air quality in Beijing than nonlocal emission *** the emission reduction scenario,local,controlled regions,other regions,and boundary conditions contributed 47.7%,42.0%,5.3%,and 5.0%to the PM_(2.5)concentrations in Beijing,*** results indicate that during the cleaning period with the air masses from the northwest,the abatements of PM_(2.5)were mainly caused by local emission ***,during the potential pollution period with the air masses from the east-northeast and west-southwest,the abatements of PM_(2.5)were caused by both local and nonlocal emission reductions almost *** implies that regional coordinated prevention and control strategies need to be arranged scientifically and rationally when heavy pollution events are forecasted.

关键词： PM_(2.5) WRF-CMAQ Meteorological conditions Emission reductions Winter Olympic games

DETERMINATION OF CLOSURE EFFECT IN FATIGUE CRACKING BY MEANS OF COMPLIANCE TECHNIQUE AND NUMERICAL METHOD

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Acta Metallurgica Sinica(English Letters) 1992年第1期5卷 38-42页

作者： Cheng Yuren Shi Xiaofeng Peng Xiang Hou Binglin northern jiaotong univ Beijing China

The crack tip strain gauge method in the compliance technique was used to determine the opening load of notched crack of axle steel,and the nonlinear finite element ADINA program, to which the cyclic stress-strain curve of axle steel was applied,was used to analyze the stress-strain field ahead of the crack tip and the opening load of notched *** results of both the compliance technique and the numerical method were in good *** this pa- per,the concept of the sensitive point is proposed and the key to the determination of the crack opening load in the experiment is to place a strain gauge at sensitive *** is certified by both experimental and numerical methods that the sensitive point has the best linear relation- ship character and the value of strain is much greater.

关键词： crack closure effect compliance technique numerical method axle steel

Study on the Performance of the nonlinear Joint Transform Correlator

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Chinese Journal of Lasers 1997年第2期B6卷 122-130页

作者： QIN Yuwen GE BaozhenCHEN Ximing ZHANG Yimol JIAN Shuisheng(Institute of Lightwave Technology,northern jiaotong university, Beijing 100044)(Institute of Optoelectronic and Precision Engineering , Tianjin university, Tianjin 300072 China) northern jiaotong univ Beijing China

We present the nonlinear joint transform correlation computer simulation results and the optical experimental results of the scale and rotation varying objects, as well as the statistical experimental results of the autocorrelation peak distribution of the object. The given experimental results show clearly that the optical experimental system is a nonlinear joint transform correlation system and the distribution of the autocorrelation peak is to some extent random. Correlation peak signal intensity of the nonlinear joint transform correlation system has no obvious variation when the scale variation of the object is less than 10% or the rotation angle variation of the object is less than 5 degrees.

关键词： optical pattern recognition real-time joint transform correlation nonlinear joint transform correlation