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Chinese Medical Journal 2010年第11期123卷 1373-1376页

作者： HOU Lei wei Yi-dong SONG Jing CHE Wen-liang PENG Wen-hui WANG Yong LI wei-ming xu ya-wei HU Da-yi Department of Cardiology Tenth People's Hospital 'l'ongJ1University Shanghai 200072 China Medical College Tongji University Shanghai 200072 China

Background The transradial approach is regarded as a useful vascular site for coronary procedures. The aim of this study was to test whether 4Fr catheters assisted by ACIST variable rate injector system can produce comparable angiographic quality and reduce the risk of radial artery injury compared to hand manifold 6 Fr catheters. Methods A total of 1816 patients were studied consecutively, among whom 856 patients received coronary angiography by 4 Fr catheters （4Fr group） and 960 patients by 6 Fr catheters （6Fr group）. Angiographic and procedural characteristics were observed and recorded. The luminal inner radial arterial diameter before and after the procedure were collected. Results The baseline clinical characteristics were similar in both groups. There were no significant differences in procedure time, radiation dose and quality scores in both groups （P 〉0.05）, but more contrast media was delivered in the 6Fr group （P 〈0.001）. The mean radial arterial diameter six months after the procedure in the 6Fr group reduced significantly compared to that measured one day prior to the procedure （P 〈0.001）. Conclusions Coronary angiography using the 4Fr catheters with Acist power injection system can achieve an acceptable diagnostic quality while at the same time minimizing radial artery injury and contrast media consumption.

关键词： angiography radial artery catheterization ultrasonography

A randomized prospective comparison of CartoMerge and CartoXP to guide circumferential pulmonary vein isolation for the treatment of paroxysmal atrial fibrillation

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Chinese Medical Journal 2008年第6期121卷 508-512页

作者： TANG Kai MA Jian ZHANG Shu ZHANG Jing-ying wei Yi-dong CHEN yan-qing YU xue-jing xu ya-wei Department of Cardiology Shanghai Tenth People's HospitalTongii University Shanghai 200072 China Centre of Arrhythmia Diagnosis and Treatment FuwaiCardiovascular Hospital Chinese Academy of Medical Sciencesand Peking Union Medical College Beijing 100037 China

Background CartoXP and CartoMerge have been used to treat atrial fibrillation （AF） for several years. Our randomized prospective study compared clinical outcomes of these two versions of three dimensional electroanatomic mapping system in guiding catheter ablation for paroxysmal atrial fibrillation （PAF）. Methods Eighty-one patients with symptomatic, drug refractory PAF were randomly assigned to CartoMerge group （n=-42, mean age （54.5 ＋ 13.1） years, history of AF = 3.2 years） or CartoXP group （n=39, mean age （59.8 ± 15.6） years, history of AF = 2.9 years）. All patients underwent 64-slice computed tomography （MSCT） 1 to 3 days prior to ablation procedure. Using CartoMergeTM Image Integration Module, 3D anatomical images of the left atrium （LA） and pulmonary veins （PVS） derived from MSCT of CartoMerge group were established and merged with the electroanatomical map. The integrated images were used to guide the procedure of circumferential pulmonary vein isolation （CPVl）. In the other group, CPVl was guided just by CartoXP. The endpoint of CPVl in both groups was abolition or dissociation of pulmonary vein potentials （PVPs）. Results Mapping points to establish the electroanatomical model of the LA/PVs were 48.7＋13.4 in CartoMerge group and 62.5±15.7 in CartoXP group （P〈0.001）. Mean distance between mapping points and the MSCT surfaces in CartoMerge group was （1.59±0.33） mm. Accomplishment of abolition or dissociation of PVPs was achieved 95.2% in CartoMerge group and 92.3% in CartoXP group. Durations of procedure and exposure to X-ray were （156±25） minutes, （179±21） minutes （P〈0.001） and （19.6±7.5） minutes, （28.5±12.8） minutes （P 〈0.001）, respectively. After a follow-up with duration of （11.9＋3.1） months vs （12.4±3.6） months post the first ablation procedure, patients free of AF were 33 （78.6%） in CartoMerge group and 29 （74.4%） in CartoXP group （P〉0.50）. No patient suffered pulmonary vein stenosis, atenoesophageal fistula, stroke or death. Conclusion Compared to Carto

关键词： CartoMerge CartoXP circumferential pulmonary vein isolation paroxysmal atrial fibrillation electroanatomical mapping

A novel non-overlapping approach to accurately represent 2D arbitrary particles for DEM modelling

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Journal of Central South University 2017年第1期24卷 190-202页

作者：张强徐卫亚刘沁雅王伟孟庆祥 Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering Hohai UniversityNanjing 210098China Research Institute of Geotechnical Engineering Hohai UniversityNanjing 210098China Department of Physics University of TorontoTorontoM5S 1A7Canada Department of Civil&Environmental Engineering University of WaterlooWaterlooN2L 3G1Canada

Mechanical behaviors of granular materials are complicated and greatly influenced by the particle ***,some composite approaches have been proposed for realistic particle shape modelling within discrete element method(DEM),while they cannot give a good representation to the shape and mass properties of a real *** this work,a novel algorithm is developed to model an arbitrary particle using a cluster of non-overlapping *** algorithm mainly consists of two components:boundary filling and domain *** the boundary filling,some disks are placed along the boundary for a precise representation of the particle shape,and some more disks are placed in the domain to give an approximation to the mass properties of the particle in the domain ***,a simple method is proposed to correct the mass properties of a cluster after domain filling and reduce the number of the disks in a cluster for lower computational ***,it is another great merit of the algorithm that a cluster generated by the algorithm can be used to simulate the particle breakage because of no overlaps between the disks in a ***,several examples are used to show the robust performance of the algorithm.A current FORTRAN version of the algorithm is available by contacting the author.

关键词： discrete element method (DEM) composite approaches arbitrary particles clusters non-overlapping disks

Percutaneous Ventricular Restoration Therapy Using the Parachute Device in Chinese Patients with Ischemic Heart Failure： Three-Month Primary End-point Results of PARACHUTE China Study

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Chinese Medical Journal 2016年第17期129卷 2058-2062页

作者： Yue-Jin yang Yong Huo ya-wei xu Jian-An Wang ya-Ling Han Jun-Bo Ge Rui-yan Zhang Xiao-yan yan Run-Lin Gao Department of Cardiology Fu Wai Hospital National Center for Cardiovascular Diseases Chinese Academy of Medical Sciences Belling 100037 China Department of Cardiology Peking University First Hospital Beijing 100034 China Department of Cardiology Shanghai Tenth People's Hospital Tongji University Shanghai 200072 China Department of Cardiology The Second Affiliated Hospital of Zhejiang University Hangzhou Zhejiang 310009 China Department of Cardiology The General Hospital of Shenyang Military Region Shenyang Liaoning 110000 China Department of Cardiology Fudan University Zhongshan Hospital Shanghai 200032 China Department of Cardiology School of Medicine Shanghai Jiaotong University Ruijin Hospital Shanghai 200025 China Department of Biostatistics Peking University Clinical Research Institute Beijing 100191 China

Background： The primary cause of ischemic heart failure （HF） is myocardial infarction （MI） resulting in left ventricle （LV） wall motion abnormality secondary to ventricular remodeling. A prospective, nonrandomized study conducted in China was designed to assess safety and efficacy of the percutaneous ventricular restoration therapy using Parachute device （CardioKinetix, lnc., CA, USA） in ischemic HF patients as a result of LV remodeling after anterior wall M1. Methods： Thirty-one patients with New York Heart Association （NYHA） Class I1, I11 ischemic HF, ejection traction between 15% and 40%, and dilated akinetic or dyskinetic anterior-apical wall without the need to be revascularized were enrolled from seven sites in China from October to December 2014. The Parachute device was implanted through femoral artery. All patients received low-dose aspirin and anticoagulation with warfarin tbr at least 12 months postdevice implantation. The primary end-point was the assessment of efficacy as measured by the reduction in LV end-systolic volume index （LVESVI） against baseline LVESVI at 3 months postdevice implantation, determined by the echocardiography and measured by echocardiography core laboratory. Quality of life was assessed using EQ-SD and visual analog scale （VAS）. For quantitative data comparison, paired t-test （normality data） and signed-rank test （abnormality data） were used： application of signed-rank test was tbr the ranked data comparison. Results： A change in LVESVI as measured by echocardiography from the preimplant baseline to 3-month postdevice implantation revealed a statistically significant reduction from 77.5 ~ 20.0 ml/m-＇ to 53,1 ~ 17.0 ml/m-＂（P 〈 0.0001 ）, The trial met its primary end-point. Of the 31 patients, the procedural success was 96.8%. Overall, NYHA HF class assessment results showed an improvement of more than halfa class at 3 months （P 〈 0.001 ）. Quality of life assessed by the VAS value increased 11.5 points （P 〈 0.01 ）, demonstrating im

关键词： lschemic Heart Failure Left Ventricle Remodeling Percutaneous Ventricular Restoration Structural Heart

Creep properties and permeability evolution in triaxial rheological tests of hard rock in dam foundation

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Journal of Central South University 2012年第1期19卷 252-261页

作者： xu wei-ya WANG Ru-bin WANG wei ZHANG Zhi-liang ZHANG Jiu-chang WANG Wen-yuan Research Institute of Geotechnical Engineering Hohai UniversityNanjing 210098China College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing 210098China Kunming Design and Research Institute China Hydropower Consulting Group Co.Kunming 650051China

Triaxial creep tests were carried out under seepage pressure by using rock servo-controlled triaxial rheology testing equipment. Based on experimental results, rock rheological properties influenced by seepage-stress coupling were studied, and variations of seepage rate with time in complete creep processes of rock were analyzed. It is shown that, when the applied stress is less than failure stress level, the creep deformation is not obvious, and its main form is steady-state creep. When applied stress level is greater than or less than but close to fracture stress, it is easier to see the increase of creep deformation and the more obvious accelerative creep characteristics. The circumferential creep deformation is obviously higher than the axial creep deformation. At the stage of steady-state creep, the average of seepage flow rate is about 4.7×10-9 rn/s at confining pressure （tr3） of 2 MPa, and is about 3.9×10-9 m/s at a3 of 6 MPa. It is seen that the seepage flow rate at or3 of 2 MPa in this case is obviously larger than that at tr3 of 6 MPa. At the stage of creep acceleration, the seepage flow rate is markedly increased with the increase of time. The variation of rock permeability is directly connected to the growth and evolution of creep crack. It is suggested that the permeability coefficient in complete creep processes of rock is not a constant, but is a function of rock creep strain, confining pressure, damage variable and pore water pressure. The results can be considered to provide a reliable reference for the establishment of rock rheological model and parameter identification.

关键词： rock mechanics creep properties volcanic breccia triaxial rheology test permeability evolution creep damage

Stress dependent permeability and porosity of low-permeability rock

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Journal of Central South University 2017年第10期24卷 2396-2405页

作者： JIA Chao-jun xu wei-ya WANG Huan-ling WANG Ru-bin YU Jun yaN Long Research Institute of Geotechnical Engineering Hohai UniversityNanjing 210098China Department of Civil Engineering University of TorontoToronto M5S 1W8Canada Key Laboratory of Coastal Disaster and Defense Ministry of EducationHohai UniversityNanjing 210098China

The seepage property of low-permeability rock is of significant importance for the design and safety analysis of underground cavities. By using a self-developed test system, both permeability and porosity of granite from an underground oil storage depot were measured. In order to study the influence of rock types on permeability, a tight sandstone was selected as a contrast. The experimental results suggested that the porosity of this granite is less than 5% and permeability is low to 10–20 m^2 within the range of effective stress. During the loading process, both exponential relationship and power law can be utilized to describe the relationship between effective stress and permeability. However, power law matches the experimental data better during the unloading condition. The stress dependent porosity of granite during loading process can be described via an exponential relationship while the match between the model and experimental data can be improved by a power law in unloading paths. The correlation of permeability and porosity can be described in a power law form. Besides, granite shows great different evolution rules in permeability and porosity from sandstone. It is inferred that this difference can be attributed to the preparing of samples and different movements of microstructures subjected to effective stress.

关键词： permeability porosity effective stress steady-state method transient pulse method low-permeability

Enhancing reversible hydrogen storage performance of 2LiBH4–MgH2 via in-situ building heterogeneous nucleation sites

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Rare Metals 2024年第9期43卷 4367-4376页

作者： wei Chen ya-Hui Sun Tian xu xue-Bin Yu Guang-Lin Xia Department of Materials Science Fudan University

2LiBH4-MgH2composite is one of the most attractive reactive hydride composites with a theoretic hydrogen capacity of 10.8 wt%.However,the large nucleation restriction of MgB2during the second step of dehydrogenation results in sluggish hydrogen storage kinetics and high operating temperature,which hinders its practical application as on-board hydrogen storage ***,Al3Ti doped Al nanoparticles （AT NPs） are prepared by a facile chemical reduction reaction to improve the hydrogen storage performance of *** the initial H2desorption process,MgAlB4and TiB2that have identical crystal structure and low d-value mismatch with MgB2resulting from the reaction between AT NPs and 2LiBH4-MgH2composite serve as effective nucleation sites for the formation of *** a result,the apparent activation energy of the two-step H2desorption of AT NPs doped 2LiBH4-MgH2composite are notably decreased to （110.0±5.9） and（119.6±1.4） kJ·mol-1,which is 55.5 and 33.5 kJ·mol-1lower than that of the undoped *** importantly,a reversible hydrogen storage capacity of 9.2 wt%after 10cycles of H2desorption and adsorption could be achieved,corresponding to a capacity retention rate of 99%.The building of reactive bimetallic catalyst towards in situ formation of heterogeneous nucleation sites provides a new strategy for improving the hydrogen storage performance of reactive hydride composites.

关键词： Catalytic effects Heterogeneous nucleation Reactive hydride composites Reversible hydrogen storage

The mechanical response of piles with consideration of pile-soil interactions under a periodic wave pressure

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Journal of Hydrodynamics 2014年第6期26卷 921-929页

作者：王环玲徐卫亚朱峰 Key Laboratory of Coastal Disaster and Defence Ministry of Education Hohai University Department of Civil Engineering University of Toronto Institute of Geotechnical Engineering Hohai University

The pile-soil interaction under wave loads is an extremely complex and difficult issue in engineering. In this study, a physical model test is designed based on the principle of the gravity similarity to obtain time histories of wave forces of unsteady regular waves, and to measure the magnitude and the distribution of wave forces acting on the piles. A numerical model and relevant numerical methods for the pile-soil contact surface are adopted based on the principles of elastic dynamics. For a practical project, the time histories of wave forces on the piles are obtained through physical model tests. The deformations of the piles in the pile-soil interactions and the distribution of the bending moment on the piles are studied. It is shown that, with the increase of the period of wave pressures, the absolute value of the horizontal displacement of the piles increases, the embedment depth of the piles increases, and the scope of influence of soils increases. The change of the bending moment on the piles is consistent with that of its theoretical results, and the proposed numerical method can very well simulate the properties of the piles.

关键词： periodic wave pressure pile-soil interaction non-linear contact numerical calculation

Limitation standard of toxic aconitines in Aconitum proprietary Chinese medicines using on-line extraction electrospray ionization mass spectrometry

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Acta Pharmaceutica Sinica B 2020年第8期10卷 1511-1520页

作者： Zi-Dong Qiu xu-ya wei Rui-Qi Sun Jin-Long Chen Ting Tan Jia-Quan xu Guang-Hong Cui Tong Chen Juan Guo Chang-Jiang-Sheng Lai Lu-Qi Huang State Key Laboratory Breeding Base of Dao-di Herbs National Resource Center for Chinese Materia MedicaChina Academy of Chinese Medical SciencesBeijing 100700China The National Pharmaceutical Engineering Center for Solid Preparation in Chinese Herbal Medicine Jiangxi University of Traditional Chinese MedicineNanchang 330006China State Key Laboratory of Natural Medicines China Pharmaceutical UniversityNanjing 210009China Jiangxi Key Laboratory for Mass Spectrometry and Instrumentation College of ChemistryBiology and Material SciencesEast China Institute of TechnologyNanchang 330013China

Development of rapid analytical methods and establishment of toxic component limitation standards are of great importance in quality control of traditional Chinese medicine. Herein, an online extraction electrospray ionization mass spectrometry(oEESI-MS) coupled with a novel whole process integral quantification strategy was developed and applied to direct determination of nine key aconitine-type alkaloids in 20 Aconitum proprietary Chinese medicines(APCMs). Multi-type dosage forms(e.g., tablets, capsules, pills, granules, and liquid preparation) of APCM could be determined directly with excellent versatility. The strategy has the characteristics of high throughput, good tolerance of matrix interference, small amount of sample(~0.5 mg) and reagent(~240 μL) consumption, and short analysis time for single sample(weight toxicity(HWT) evaluation and the Chinese Pharmacopoeia severally, and turned out that HWT-based toxicity evaluation results were closer to the real clinical applications. Hence,a more accurate and reliable APCM toxicity limitation was established and expected to play an important guiding role in clinics. The current study extended the power of ambient MS as a method for the direct quantification of molecules in complex samples, which is commonly required in pharmaceutical analysis,food safety control, public security, and many other disciplines.

关键词： Aconitum dosage tablets

Effects of Combinatorial Expression of selA, selB and selC Genes on the Efficiency of Selenocysteine Incorporation in Escherichia coli

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Chemical Research in Chinese Universities 2013年第1期29卷 87-94页

作者： xu ya-wei JIANG Zhi-hua MU Ying ZHANG Lei ZHAO Si-qi LIU Shu-jun WANG Cheng ZHAO yang LU Shao-wu Key Laboratory for Molecular Enzymology and Engineering Ministry of Education Jilin University Changchun 130012 P. R. China Research Center for Analytical Instrumentation Institute of Cyber-Systems and ControlState Key Laboratory of lndustrial Control Technology Zhejiang University Hangzhou 310058 P. R. China Department of Bioengineering Jilin Agricultural Science and Technology College Jilin 132001 P. R. China Pulmonary Center School of Medicine Boston University Boston MA 02118 USA

In Escherichia coil four gene products（selA, selB, selC and selD） and a selenocysteine（Sec） insertion sequence（SECIS） are required for the correct translation of UGA codons encoding Sec. Previous studies have shown that the stoichiometry of selenoproteine mRNA and elongation factor SelB affect the efficiency of Sec incorporation. Herein lies a detailed analysis of the effects of co-expressing selA, selB and selC genes under inducible promoters on the incorporation efficiency of Sec. Over-expression of either selA or selB reduced the efficiency of Sec incorporation by 61.1% or 11.6%, respectively, compared to the over-expression of the reporter vector alone did. Concomitant over-expression ofselC with selA or selB completely reversed the reduce of the efficiency of Sec but still reduced the efficiency of the incorporation relative to that observed for expression of selC alone. Over-expression of selC gene alone under L-arabinose induction reduced the efficiency of the incorporation relative to that observed for co-expressing selC with selA and selB under the control of its endogenous promoter in the absence of L-arabinose. Co-expression of selA, selB and selC with selA or selB under the control of inducible promoters increased the effi- ciency of Sec incorporation by 69.7%. Moreover, inducing selenoprotein-related gene expression during the late exponential phase increased the efficiency of Sec incorporation by a factor of 5.4 relative to that observed for the reporter vector alone. These results suggest that the co-expression of selA, selB and selC in Escherichia coli under the control of inducible promoters is a viable and promising strategy for increasing the yields of selenoproteins.

关键词： Selenocysteine SelA SelB SelC Combinatorial expression