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World Journal of Clinical Cases 2025年第4期13卷 41-47页

作者： Xing-Po Li Zi-shan wang Hong-Xia Yu shan-shan wang Department of Cardiovascular Medicine Huantai County Hospital of Traditional Chinese MedicineZibo 256400Shandong ProvinceChina Department of Cardiovascular Medicine Zibo Hospital of Integrated Traditional Chinese and Western MedicineZibo 255500Shandong ProvinceChina

BACKGROUND The incidence of acute myocardial infarction(AMI)is rising,with cardiac rupture accounting for approximately 2%of deaths in patients with acute ST-segment elevation myocardial infarction(STEMI).Ventricular free wall rupture(FWR)occurs in approximately 2%of AMI patients and is notably rare in patients with *** of cardiac rupture include left ventricular FWR,ventricular septal rupture,and papillary muscle *** FWR usually leads to acute cardiac tamponade or electromechanical dissociation,where standard resuscitation efforts may not be *** septal rupture and papillary muscle rupture often result in refractory heart failure,with mortality rates over 50%,even with surgical or percutaneous repair *** SUMMARY We present a rare case of an acute non-STEMI patient who suffered sudden FWR causing cardiac tamponade and loss of consciousness immediate before undergoing coronary *** resuscitation and emergency open-heart repair along with coronary artery bypass grafting resulted in successful patient *** This case emphasizes the risks of AMI complications,shares a successful treatment scenario,and discusses measures to prevent such complications.

关键词： Acute non-ST segment elevation myocardial infarction Cardiac rupture Acute myocardial infarction Free wall rupture Case report

Simulations of electron zebra stripes in the inner radiation belt using a composite empirical electric field model

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Science China Earth Sciences 2025年第1期 27-38页

作者： Ziyang wang Ying LIU Qiugang ZONG Hong ZOU Yuguang YE Xuzhi ZHOU Chao YUE shan wang Institute of Space Physics and Applied Technology Peking University State Key Laboratory of Lunar and Planetary Science Macau University of Science and Technology

The phenomenon termed “zebra stripes” manifests as regular patterns in the energy-space(L shell) spectrum of energetic electrons(ranging from tens to hundreds ke V) within the inner radiation belt. These structures exhibit drift-periodic behavior and commonly arise from large-scale electric field perturbations near the substorm onsets. In this study, we introduce a composite electric field model and replicate the formation, structure, and evolution of zebra stripes using a bounce-averaged test particle code under this electric field model. High-resolution measurements of energetic electrons obtained from the Van Allen Probes and the recently launched Macao Science Satellites-1 are used as initial conditions and served to validate our test particle simulations. Comparative analyses between observed data and simulations demonstrate our test particle method's efficacy in capturing zebra stripes' general behavior. Moreover, the composite model proves capable of reproducing realistic variations in the electric field within the inner radiation belt to a certain extent. Nevertheless, subtle differences emerge in the flux strength and the positions of stripes. These disparities primarily stem from limitations inherent in the electric field model and the initial conditions of the simulation. Acknowledging that the model represents an average case, it is conceivable that real-world scenarios may deviate from the average, thereby introducing variations in the observed phenomena.

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Le Système d’Euler de Kato en Famillie(Ⅱ)

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Acta Mathematica Sinica,English Series 2021年第1期37卷 173-204页

作者： shan Wen wang School of Mathematics Renmin University of ChinaBeijing 100872P.R.China

This article is the second article on the generalization of Kato’s Euler *** main subject of this article is to construct a family of Kato’s Euler systems over the cuspidal eigencurve,which interpolate the Kato’s Euler systems associated to the modular forms parametrized by the cuspidal *** also explain how to use this family of Kato’s Euler system to construct a family of distributions on Z_p over the cuspidal eigencurve;this distribution gives us a two-variable p-adic L function which interpolate the p-adic L function of modular forms.

关键词： Kato’s Euler system p-adic modular forms p-adic L functions

An Improved Ionospheric Delay Correction Method for SBAS

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Chinese Journal of Electronics 2021年第2期30卷 384-389页

作者： wang shan wang Ding GUAN Yingxuan China University of Mining and Technology-Beijing

The existing ionospheric delay correction methods in Satellite based augmentation system(SBAS)were just for single constellation and over *** this paper, we propose a new method to make more accurate ionospheric delay correction and tighter error bound orienting towards GPS and GLONASS. Considering that some Ionospheric pierce points(IPPs) are almost motionless, we make a filtering process to estimate the ionospheric delays at Ionospheric grid points(IGPs) to better reflect the ionospheric temporal variation. Then we conduct a simulation on ionospheric delay estimation at IGPs in dual constellations through planar fit method and filtering method. It can be concluded that the filtering method can bound the ionospheric delay correction error more tightly, simultaneously the ionospheric delay correction accuracy is improved a bit.

关键词： simultaneously the ionospheric delay correction accuracy existing ionospheric delay correction methods single constellation satellite navigation ionospheric delay correction error ionospheric temporal variation Global Positioning System ionospheric electromagnetic wave propagation SBAS tighter error bound orienting accurate ionospheric delay correction ionospheric delays ionospheric delay estimation filtering method ionospheric techniques Ionospheric pierce points Ionospheric grid points improved Ionospheric delay correction method Satellite based augmentation system ionosphere planar fit method delays delay estimation

Preparation and desulfurization activity of nano-CeO_2/γ-Al_2O_3 catalysts

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Rare Metals 2018年第7期37卷 554-560页

作者： Qi Yang Hui Hu shan-shan wang School of Environment Science and Engineering Huazhong University of Science and Technology Department of Urban Construction Wuchang Shouyi University Wuhan Zuoling New Town Development and Investment Co. Ltd.

γ-A12O3-supported CeO2 catalysts were pre- pared by microemulsion and impregnation methods and characterized by X-ray diffraction （XRD） and scanning electron microscope （SEM） techniques. At the same time, the desulfurization activity of catalysts was investigated. The results show that nanoscale active substances and a high desulfurization effect are achieved by microemulsion, exhibiting a significant dominance compared with traditional impregnation method. The optimal preparation condition is temperature of 30 ℃ and ratio of [H20]/[surface active agent] of 7 with slow demulsification. The activated catalysts still keep high and stable desulfurization activity during a wide temperature range of 450-600 ℃. Among a series of prepared catalysts, the desulfurization rate of 6CeOz/γ-A1203 is the highest, reaching up to 80 % when temperature is higher than 550℃. The catalytic reduction mechanism of SO2 over nano-CeOz/γ-A1203 follows redox mechanism.

关键词： Nano-CeO2/γ-Al2O3 Microemulsion Catalyst Desulfurization

A flexible model-free tram signal priority method with a large coordination scope in China

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Transportation Safety and Environment 2024年第3期6卷 28-34页

作者： shan wang shanghai Urban Construction Design and Research Institute No.3447 Dongfang RoadPudong DistrictShanghai 200125China

Tram systems with the advantages of reliable operation,comfort,low emissions and moderate capacity have been quite popular in recent years in ***,there are still problems with tram signal control(*** model,signal control strategies).In-depth analysis on existing operational issues of trams,calculation of two evaluation indexes,as well as a flexible model-free tram signal priority method were developed to deal with tram *** research in Songjiang District,shanghai shows that:(1)The function of the green extension strategy is limited with c.a.10%tram priority improvement,while the optimal one can reach to 85%higher on average.(2)A scheme with a benefit for trams and with no negative impact,and even benefits,for general traffic can be realized.(3)The optimal solution is beneficial for intersections with a maximum c.a.70%amelioration with delay decreasing from 132.7 s/vehicle to 40.89 s/vehicle,or from 104.77 s/capita to 22.31 s/*** paper has great significance for the signal optimization and safety of tram systems,even the development of a comprehensive transportation system for a city.

关键词： tram signal priority large coordination scope model-free signal control average passenger delay average vehicle delay

Sharp Upper Bounds for λ_1^(L_r) of Immersed Hypersurfaces and Their Stability in Space Forms

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Acta Mathematica Sinica,English Series 2008年第5期24卷 749-760页

作者： Ru shan wang College of Mathematics and Computer Science Anhui Normal University Wuhu 241000 P. R. China School of Mathematical Sciences Fudan University Shanghai 200433 P. R. China

In this paper we derive new sharp upper bounds for the first positive eigenvalue λ1^Lr of the linearized operator of the higher order mean curvature of a closed hypersurface immersed into a Riemannian space form R^（n＋l）（c）（c 〉 0）. Our bounds are extrinsic in the sense that they are given in terms of the higher order mean curvatures. Under the assumption Hr＋2 〉 0, by establishing two valuable integral formulas, we obtain unified sharp upper bounds of λ1^Lr. We also give an estimation of the upper bounds of the first eigenvalue of a SchrSdinger-type operator, by which we prove those hypersurfaces with positive constant Hr＋l in any space forms are stable if and only if they are geodesic spheres, thus generalizing the previous result obtained only in the case c≤0.

关键词： r-mean curvature Schrodinger-type operator stability geodesic hypersphere

State and fate of the remaining tropical mountain glaciers in Australasia using satellite imagery

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Journal of Mountain Science 2018年第3期15卷 495-503页

作者： Bijeesh Kozhikkodan VEETTIL wang shan-shan Department for Management of Science and Technology Development Ton Duc Thang University Faculty of Environment and Labour Safety Ton Duc Thang University Key Laboratory of Arid Climate Change and Reducing Disaster of Gansu Province & Key Open Laboratory of Arid Climate Change and Disaster Reduction of CMA Institute of Arid Meteorology CMA

Tropical glaciers are extremely sensitive to a warming climate. In this paper, the evolution of the remaining tropical glaciers in Australasia(Irian Jaya, Indonesia) during the period 1988-2015 was quantified. Landsat series images, a digital elevation model from SRTM, and previously published data were used. Estimated total glacier area in 1988, 1993, 1997 and 2004 was 3.85 km2±0.13 km2, 3.01 km2±0.08 km2, 2.49 km2±0.07 km2 and 1.725 km2 ±0.042 km2, respectively. Only 0.58 km2±0.016 km2 glacierized area remained in 2015 in Puncak Jaya, which is about 84.9% loss in just 27 years. If this rate continued, the remaining tropical glaciers in Australasia would disappear in the 2020 s. Timeseries analysis of climate variables showed significant positive trends in air temperature(0.009°C per year) and relative humidity(0.43% per year) but no considerable tendency was observed for precipitation. Warming climate together with mining activities would accelerate loss of glacier coverage in this region.

关键词： Glacier shrinkage Puncak Jaya Tropical glaciers Climate change

Empirical Likelihood Inference for a Partially Linear Errors-in-variables Model with Covariate Data Missing at Random

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Acta Mathematicae Applicatae Sinica 2016年第2期32卷 305-318页

作者： shan-shan wang Heng-jian CUI School of Economics and Management Beihang UniversityBeijing 100191China Beijing Key Laboratory of Emergency Support Simulation Technologies for City Operations Beijing 100191China School of Mathematical Sciences&:BCMIIS Capital Normal UniversityBeijing 100048China

The authors study the empirical likelihood method for partially linear errors-in-variables model with covariate data missing at random. Empirical likelihood ratios for the regression coeffidents and the baseline function are investigated, and the corresponding empirical log-likelihood ratios are proved to be asymptotically standard chi-squared, which can be used to construct confidence regions. The finite sample behavior of the proposed methods is evaluated by a simulation study which indicates that the proposed methods are comparable in terms of coverage probabilities and average length of confidence intervals. Finally, the Earthquake Magnitude dataset is used to illustrate our proposed method.

关键词： chi-square distribution confidence region coverage probability empirical likelihood partiallylinear model

The Maximum Surplus before Ruin and Related Problems in a Jump-Diffusion Renewal Risk Process

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Acta Mathematica Sinica,English Series 2011年第12期27卷 2379-2394页

作者： shan shan wang Chun Sheng ZHANG Department of Mathematics Tianjin Polytechnic University Tianjin 300160 P. R. China School of Mathematics and LPMC Nankai University Tianjin 300071 P. R. China

In this paper, we investigate a Sparre Andersen risk model perturbed by diffusion with phase-type inter-claim times. We mainly study the distribution of maximum surplus prior to ruin. A matrix form of integro-differential equation for this quantity is derived, and its solution can be expressed as a linear combination of particular solutions of the corresponding homogeneous integro-differential equations. By using the divided differences technique and nonnegative real part roots of Lundberg＇s equation, the explicit Laplace transforms of particular solutions are obtained. Specially, we can deduce closed-form results as long as the individual claim size is rationally distributed. We also give a concise matrix expression for the expected discounted dividend payments under a barrier dividend strategy. Finally, we give some examples to present our main results.

关键词： Sparre Andersen risk model phase-type inter-claim times maximum surplus before ruin,expected present value of dividends barrier dividend strategy diffusion integro-differential equation