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Anemia and risk of periprocedural cerebral injury detected by diffusion-weighted magnetic resonance imaging in patients undergoing transcatheter aortic valve replacement

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World Journal of Emergency Medicine 2022年第1期13卷 32-39页

作者： Stella ng Qi-feng Zhu ju-bo Jiang Chun-hui Liu Jia-qi Fan Ye-ming Xu Xian-bao Liu Jian-an Wang Department of Cardiology the Second Affi liated Hospital of Zhejiang University School of MedicineHangzhou 310009China Zhejiang University School of Medicine Hangzhou 310058China

BACKGROUND: Anemia is prevalent in patients undergoing transcatheter aortic valve replacement(TAVR) and has been linked to impaired outcomes after the procedure. Few studies have evaluated the impact of anemia and new ischemic lesions post ***: We prospectively enrolled 158 patients who received TAVR in our center. Anemia was defined according to the World Health Organization criteria as hemoglobin ng(DW-MRI) procedure before and within 4–7 days after TAVR. RESULTS: Anemia was present in 85(53.8%) patients who underwent TAVR, and 126(79.7%) patients had 718 new DW-MRI positive lesions with a mean of 4.54±5.26 lesions per patient. The incidence of new ischemic lesions was 81.2% in patients with anemia versus 78.1% in patients without anemia(P=0.629). Moreover, anemic patients had bigger total volume/lesions in the anterior cerebral artery/middle cerebral artery(ACA/MCA) and MCA regions compared to the non-anemic patients(31.89±55.78 mm^(3) vs. 17.08±37.39 mm^(3), P=0.049;and 54.54±74.72 mm^(3) vs. 33.75±46.03 mm^(3), P=0.034). Anemia was independently associated with the volume/lesion in the ACA/MCA(β=16.796, 95% confidence interval [95% CI] 2.001 to 31.591, P=0.026) and in the MCA zone(β=0.020, 95% CI 0.001 to 0.040, P=0.041). CONCLUSIONS: Patients with pre-procedural anemia may have bigger total volume/lesions in the ACA/MCA and MCA regions compared to the non-anemic patients. Whether the consequences of bigger total volume/lesions impact neurological and cognitive outcomes remains to be investigated.

关键词： Aortic stenosis Anemia Cerebral ischemic lesions Transcatheter aortic valve replacement

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Review on cryogenic technologies for CO_(2) removal from natural gas

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Frontiers in Energy 2022年第5期16卷 793-811页

作者： Yujing BI Yonglin ju Institute of Refrigeration and Cryogenics Shanghai Jiao Tong UniversityShanghai 200240China

CO_(2) in natural gas(ng)is prone to condense directly from gas to solid or solidify from liquid to solid at low temperatures due to its high triple point and boiling temperature,which can cause a block of ***,CO_(2) will also affect the calorific value of *** on the above reasons,CO_(2) must be removed during the ng liquefaction *** with conventional methods,cryogenic technologies for CO_(2) removal from ng have attracted wide attention due to their nonpolluting and low-cost *** integration with ng liquefaction can make rational use of the cold energy and realize the purification of ng and the production of byproduct liquid CO_(2).In this paper,the phase behavior of the CH_(4)-CO_(2) binary mixture is summarized,which provides a basis for the process design of cryogenic CO_(2) removal from ***,the detailed techniques of design and optimization for cryogenic CO_(2) removal in recent years are summarized,including the gas-liquid phase change technique and the gas-solid phase change ***,several improvements for further development of the cryogenic CO_(2) removal process are *** removal process in combination with the phase change and the traditional techniques with renewable energy will be the broad prospect for future development.

关键词： cryogenic CO_(2)removal purification of natural gas(ng) biogas upgrading CH_(4)-CO_(2)binary system

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Ascending aortic dilatation rate after transcatheter aortic valve replacement in patients with bicuspid and tricuspid aortic stenosis: A multidetector computed tomography follow-up study

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World Journal of Emergency Medicine 2019年第4期10卷 197-204页

作者： Yu-xin He Jia-qi Fan Qi-feng Zhu Qi-jing Zhou ju-bo Jiang Li-han Wang Stella ng Xian-bao Liu Jian-an Wang Department of Cardiology the Second Affiliated HospitalZhejiang University School of MedicineHangzhou 310009China Department of Radiology the Second Affiliated HospitalZhejiang University School of MedicineHangzhou 310009China

BACKGROUND: Current data is lacking about the progression of ascending aortic dilatation after transcatheter aortic valve replacement(TAVR) in aortic stenosis(AS) patients with bicuspid aortic valve(BAV) and tricuspid aortic valve(TAV). This study aims to assess the ascending aortic dilatation rate(mm/year) after TAVR in patients with BAV versus TAV using a multidetector computed tomography(MDCT) fol ow-up and to determine the predictors of ascending aortic dilatation ***: Severe AS patients undergoing TAVR from March 2013 to March 2018 at our center with MDCT follow-ups were included. BAV and TAV were identified using baseline MDCT. Baseline and follow-up MDCT images were analyzed,and the diameters of ascending aorta were measured. Study end point is ascending aortic dilatation rate(mm/year). Furthermore,factors predicting ascending aortic dilatation rate were also ***: Two hundred and eight patients were included,comprised of 86 BAV and 122 TAV patients. Five,4,3,2,and 1-year MDCT follow-ups were achieved in 7,9,30,46,and 116 patients. The ascending aortic diameter was significantly increased after TAVR in both BAV group(43.7±4.4 mm vs. 44.0±4.5 mm;Png aortic dilatation rate was found between BAV and TAV group(0.2±0.8 mm/year vs. 0.3±0.8 mm/year,P=0.592). Multivariate linear regression revealed paravalvular leakage(PVL) grade was independently associated with ascending aortic dilatation rate in the whole population and BAV group,but not TAV group. No aortic events occurred during ***: Ascending aortic size continues to grow after TAVR in BAV patients,but the dilatation rate is mild and comparable to that of TAV patients. PVL grade is associated with ascending aortic dilatation rate in BAV patients post-TAVR.

关键词： Transcatheter aortic valve replacement Aortic dilatation Bicuspid aortic valve

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High spectro-temporal compression on a nonlinear CMOS-chip

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Light(Science & Applications) 2021年第7期10卷 1347-1361页

作者： ju Won Choi Ezgi Sahin Byoung-Uk Sohn George F.R.Chen Doris K.T.ng Anuradha M.Agarwal Lionel C.Kimerling Dawn T.H.Tan Photonics Devices and System Group SUTD-MIT International Design CenterSingapore University of Technology and DesignSingapore 487372Singapore Institute of Microelectronics A*STAR(Agency for ScienceTechnology and Research)2 Fusionopolis Way#08-02Innovis TowerSingapore 138634Singapore Microphotonics Center Massachusetts Institute of Technology77 Massachusetts AvenueCambridgeMA 02139USA Materials Research Laboratory Massachusetts Institute of Technology77 Massachusetts AvenueCambridgeMA 02139USA Department of Materials Science and Engineering Massachusetts Institute of Technology77 Massachusetts AvenueCambridgeMA 02139USA

Optical pulses are fundamentally defined by their temporal and spectral *** ability to control pulse properties allows practitioners to efficiently leverage them for advanced metrology,high speed optical communications and attosecond ***,we report 11×temporal compression of 5.8 ps pulses to 0.55 ps using a low power of 13.3 *** result is accompanied by a significant increase in the pulse peak power by 9.4×.These results represent the strongest temporal compression demonstrated to date on a complementary metal–oxide–semiconductor(CMOS)*** addition,we report the first demonstration of on-chip spectral compression,3.0×spectral compression of 480 fs pulses,importantly while preserving the pulse *** strong compression achieved at low powers harnesses advanced on-chip device design,and the strong nonlinear properties of backend-CMOS compatible ultra-silicon-rich nitride,which possesses absence of two-photon absorption and 500×larger nonlinear parameter than in stoichiometric silicon nitride *** demonstrated work introduces an important new paradigm for spectro-temporal compression of optical pulses toward turn-key,on-chip integrated systems for all-optical pulse control.

关键词： pulse optical nonlinear

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Estimating canopy closure density and above-ground tree biomass using partial least square methods in Chinese boreal forests

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Journal of Forestry Research 2012年第2期23卷 191-196页

作者： LEI Cheng-liang ju Cun-yong CAI Ti-jiu J1ng Xia WEI Xiao-hua DI Xue-ying School of Forestry Northeast Forestry UniversityHarbin 150040P.R.China College of Geomatics Xi'an University of Science and TechnologyXi'an 710054P.R.China Department of Earth and Environmental Science University of BritishColumbia(Okanagan)3333 University wayKelownaBritish Colum-biaCanadaV1V 1V7.

Boreal forests play an important role in global environment systems. Understanding boreal forest ecosystem structure and function requires accurate monitoring and estimating of forest canopy and biomass. We used partial least square regression （PLSR） models to relate forest parameters, i.e. canopy closure density and above ground tree biomass, to Landsat ETM＋ data. The established models were optimized according to the variable importance for projection （VIP） criterion and the bootstrap method, and their performance was compared using several statistical indices. All variables selected by the VIP criterion passed the bootstrap test （p〈0.05）. The simplified models without insignificant variables （VIP 〈1） performed as well as the full model but with less computation time. The relative root mean square error （RMSE%） was 29% for canopy closure density, and 58% for above ground tree biomass. We conclude that PLSR can be an effective method for estimating canopy closure density and above ground biomass.

关键词： above-ground tree biomass bootstrap method canopy clo- sure density partial least square regression (PLSR) VIP criterion

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The first two cases of transcatheter mitral valve repair with ARTO system in Asia

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World Journal of Emergency Medicine 2020年第1期11卷 33-36页

作者： Kai-da Ren Zhao-xia Pu Lei Yu Feng Gao Li-han Wang Stella ng ju-bo Jiang Hua-jun Li Yong Xu Wei He Min Yan Xian-bao Liu Jian-an Wang Cardiovascular Department the Second Affiliated Hospital Zhejiang University School of Medicine

BACKGROUND:MAVERIC(Mitral Valve Repair Clinical Trial)validates the safety and effi cacy of the ARTO *** here report the fi rst two successful cases of utilizing the ARTO system in patients with symptomatic heart failure(HF)with functional mitral regurgitation(FMR)in ***:Two patients,aged 70 and 63,had severe HF with *** echocardiography confirmed that the left ventricular ejection fractions were less than 50%with severe mitral regurgitation(MR)in both *** drug treatment could not mitigate their ***,we used the ARTO system to repair the mitral valve for these patients on March 5 and 6,2019,***:Mitral valve repairs using the ARTO system were successfully performed under general anaesthesia for these two *** was decreased immediately after the procedures in both *** 30-day and 3-month transthoracic echocardiography(TTE)revealed a moderate to severe MR in both patients,and the New York Heart Association(NYHA)scales were also partially ***:The first two cases in Asia indicate that the ARTO system is feasible for patients with heart failure with FMR,and the patient selection appears to be crucial.

关键词： Mitral regurgitation Mitral valve repair ARTO system

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Optomechanical control of stacking patterns of h-BN bilayer

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Nano Research 2019年第10期12卷 2634-2639页

作者： Haowei Xu Jian Zhou Yifei Li Rafael Jaramillo ju Li Department of Nuclear Science and Engineering Massachusetts Institute of TechnologyCambridgeMA 02139USA Center for Advancing Materials Performance from the Nanoscale State Key Laboratory for Mechanical Behavior of MaterialsXi'an Jiaotong UniversityXi'an 710049China Department of Materials Science and Engineering Massachusetts Institute of TechnologyCambridgeMA 02139USA

Few-layer two-dime nsion al(2D)materials usually have differe nt(meta)-stable stacking patterns,which have distinet electronic and optical *** spired by optical tweezers,we show that a laser with selected freque ncy can modify the gen eralized stacking-fault en ergy Iandscape of bilayer hexagonal boron nitride(BBN),by coupling to the slip-dependent dielectric ***,BBN can be reversibly and barrier-freely switched betwee n its stacking patter ns in a controllable *** simulate the dyn amics of the stacki ng transition with a simplified equati on of motion and dem on strate that it happe ns at picosec ond *** one layer of BBN has a nearly-free surface boundary condition,BBN can be locked in its metastable stacking modes for a long *** a fast,reversible and non-volatile transition makes BBN a potential media for data storage and optical phase mask.

关键词： phase change materials two-dimensional materials opto-mechanics density functional theory

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Toughness and characterization of reactive powder concrete with ultra-high strength

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Science China(Technological Sciences) 2009年第4期52卷 1000-1018页

作者： Yang ju HongBin Liu Jian Chen YuDan Jia PeiHuo Peng State Key Laboratory of Coal Resources and Safe Mining China University of Mining & Technology Beijing 100083 China Department of Mechanical & Manufacturing Engineering The University of Calgary 2500 University Drive NW Calgary AB T2N 1N4 Canada The University of Illinois at Urbana-Champaign 1110 West Green Street Urbana IL 61801 USA Building Design Division China Nuclear Power Engineering Co. Ltd Beijing 100840 China School of Civil Engineering University of Nottingham University Park Nottingham NG7 2RD UK

A number of three-point bending and fracture tests of 200 MPa-level reactive powder concrete (RPC) with the various fiber contents have been conducted to probe the nature and characteristics of toughness of RPC200. The contribution of the embedded fibers to improving the crack-resistant capacity, energy absorption capacity and toughness with various deformation mechanisms has been analyzed. Taking account of that the first-crack deformation, peak-load deformation and their improvement varied with the fiber contents and that the deformation mechanism affected differently the performance at the first crack and the peak load, we took the peak-load deformation of plain RPC200 as the reference deformation to measure the toughness of fibered RPC200. Two toughness indices T 2(n−1)(n) and FT 2(n−1)(n) have been formulated based on P-δ responses and P-CMOD responses. The indices quantify the toughness of RPC200 with the various deformation mechanisms relative to perfectly elastoplastic materials by setting the toughness level 2(n−1) as the initial reference. It is shown that the toughness index T 2(n−1)(n) reflects the function of fibers to improve the toughness of RPC with the deformation throughout specimens, but overestimates the contribution to enhancing the toughness in post-peak periods. It underestimates, on other hands, the contribution to improving the toughness in the period from the first crack to the peak load. In contrast, the toughness index FT 2(n−1)(n) properly presents the capability that fibers absorb energy and constrain crack propagation in the matrix when the deformation is concentrated on the open crack. The proposed index unveils the contribution of fibers to toughening RPC200 both in the period from the first-crack to the peak load and in the period of post peak. This characterization method not only reveals the nature of toughness but also levels the toughness of RPC200. I

关键词： reactive powder concrete toughness characterization index deformation mechanism flexure fracture

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空间多点人工地震动幅值收敛性研究

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振动工程学报 2015年第4期28卷 610-617页

作者：吴祚菊张建经王志佳吴兴序汪明元西南交通大学土木工程学院四川成都610031 中国电建集团华东勘测设计研究院有限公司浙江杭州310014

在空间相关性人工地震动生成中,计算的繁杂和局部场地收敛性与幅值收敛性之间存在的矛盾,是时域合成法中的两大主要问题。为了简化计算,同步实现局部场地及地震动幅值的双重收敛性,在对相位角分布进行深入研究的基础上,构建了空间多点... 详细信息

在空间相关性人工地震动生成中,计算的繁杂和局部场地收敛性与幅值收敛性之间存在的矛盾,是时域合成法中的两大主要问题。为了简化计算,同步实现局部场地及地震动幅值的双重收敛性,在对相位角分布进行深入研究的基础上,构建了空间多点人工地震动幅值收敛因子,并采用虚实分离法来分解功率谱矩阵。结果表明,该方法生成的多点人工地震动计算快速,且幅值稳定收敛。

关键词：地震动合成空间相关幅值收敛性相位角分布虚实分离法

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Source Apportionment Research of Fine Particulate Matter in the Atmosphere by PAHs

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Chemical Research in Chinese Universities 2016年第5期32卷 746-753页

作者： WAng ju YAng Le MA Tianyi SUN Liyuan YU Liangui FAng Chunsheng Environmental Science Department College of Environment and Resources Jilin University Changchun 130012 P. R. China Key Laboratory of Groundwater Resources and Environment Ministry of EducationCollege of Environment and Resources Jilin University Changchun 130021 P. R. China College of Environmental Science and Engineering of Tong/i University Shanghai 200092 P. R. China Changchun Central Environmental Monitoring Station Changchun 130011 P. R. China

Haze weather frequently occurs in many cities in China. Polycyclic aromatic hydrocarbons（PAHs） in fine particulate matter（PM：.5） can adversely affect the environment and human health. In this paper, PM2.5 samples were collected at nine sites in a city in northeastern China from September 2013 to October 2014. Sixteen USEPA（US Evironment Protection Agency） priority PAHs in PM2.5 were analyzed to determine their spatial and temporal distri- bution characteristics. The source apportionment of PAHs was conducted with the Positive Matrix Factorization（PMF） model. The results indicate that the concentrations of total PAHs（T-PAHs） in PM2.5 are within the range of 0.26 to 72.48 ng/m3. The seasonal variation of T-PAHs is winter〉spring〉autumn〉summer, and the space distribution of PAHs is JZP〉DP〉BFH〉LP〉EESA〉IPT〉CP〉HZMC〉JYP. In all types of PAils, three-ring and five-ring PAHs are signifi- cantly prominent（62%） in the heating period due to petrogenic sources and traffic emissions. Middle- and high-ring PAHs in the non-heating period are caused by coal combustion and vehicle exhaust, which accounts for 77% of the total emissions. The source apportionment results obtained by the diagnostic ratio of PAHs reflect that coal burning, traffic and other sources have a distinct influence on PAH emissions in this city. Six factors are defined by PMF v5.0, namely, coke oven emissions（7.7%）, biomass burning（44.3%）, petrogenic sources（10.7%）, coal combustion（10.4%）, gasoline engine emissions（16.7%）, and diesel engine emissions（10.3%）. The results indicate that the PAHs in PM2.5 in the city are primarily caused by combustion processes and vehicle exhaust.

关键词： Polycyclic aromatic hydrocarbon(PAH) Pollution characteristics Diagnostic ratio Positive Matrix Factorization(PMF)

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