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Association between stress hyperglycemia ratio and in-hospital outcomes:findings from the improving Care for Cardiovascular Disease in China-Acute Coronary Syndrome(CCC-ACS)Project

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Journal of Geriatric Cardiology 2024年第6期21卷 658-668页

作者： Wen-Jie WANG ke-Xin WANG Jia-Long NIU Yi-xuan liu Hai-Long GE Hua SHEN On behalf of CCC-ACS investigators Department of Cardiology Beijing Anzhen HospitalCapital Medical UniversityBeijingChina

BACKGROUND Stress hyperglycemia ratio(SHR)could provide accurate information on the acute status of *** relationship between SHR and acute coronary syndrome(ACS)prognosis remains *** study was conducted to identity the association between SHR and in-hospital outcomes in patients with *** A total of 12,010 patients were eventually enrolled in the *** relationship between SHR and in-hospital major adverse cardiovascular events(MACEs)was then modeled by restricted cubic spline(RCS)curves,and all patients were divided into three groups according to the *** multivariate logistic regression analysis was used to determine the associations between the SHR and in-hospital outcomes,described as odds ratios(ORs)and 95%confidence intervals(CIs).Subgroup analyses were also performed on different *** The median age of this cohort was 63(54,71)years old,and 8942(74.5%)were *** 1 was defined as SHR1(n=5763).Compared with Group 2,Group 1(OR=1.891,95%CI:1.028-3.479,P<0.001)and Group 3(OR=1.868,95%CI:1.434-2.434,P<0.001)had higher risks of suffering from in-hospital *** was associated with higher risks of in-hospital MACEs in the subgroups of DM[OR=2.282,95%CI:1.477-3.524).CONCLUSIONS Both low and high SHR levels were independently associated with in-hospital *** males with DM,hypertension,and decreased renal function had much higher risks of suffering from SHR-correlated MACEs.

关键词： acute cardiovascular finding

The Compactness of Commutators on the Heisenberg Group

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Acta Mathematica Sinica,English Series 2006年第2期22卷 425-430页

作者： He Ping liu xuan Yuan ZHENG LMAM School of Mathematical Sciences Peking University

We consider the commutators of the HSrmander multiplier with CMO-functions on the Heisenberg group. The result of compactness on L^P spaces is proved.

关键词： Heisenberg group Multiplier Commutator CMO Compactness

The compliance contact model of cylindrical joints with clearances

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Acta Mechanica Sinica 2005年第5期21卷 451-458页

作者： Caishan liu ke Zhang Lei Yang Department of Mechanics and Engineering Science State Key Laboratory of Turbulence and Complex SystemsPeking University Beijing 100871 China Chinese Academe of Space Technology Beijing 100086 China

This paper is concerned with the determination of the normal force-displacement （NFD） relation for the contact problem of cylindrical joints with clearance. A simple formulation for this contact problem is developed by modeling the pin as a rigid wedge and the elastic plate as a simple Winkler elastic foundation. The numerical results show that the normal displacement relation based on Hertz theory is only valid for the case of large clearance with a small normal load, and the NFD relation based on Persson theory is only effective in the case of very small clearance. The proposed approximate model in this paper gives better results than Hertz theory and Persson theory in a large range of clearances as seen from the comparison with the results of FEM.

关键词： Cylindrical joint with clearance .Conformalcontact. FEM

Ligand Effects in Dinitrogen Hydrogenation of Binuclear Zirconium Complexes

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Chinese Journal of Structural Chemistry 2008年第2期27卷 238-244页

作者： liu Cai-Ping WU ke-Chen State key Laboratory of Structural Chemistry Fujian Institute of Research on theStructure of Matter The Chinese Academy of Sciences Fuzhou Fujian 350002 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China

In this work, we report a theoretical exploration of the ground-state electronic structures and molecular vibrational properties of a series of binuclear zirconium complexes in the framework of density functional theory （DFT） employing the B3LYP hybrid functional. The calculated results reveal that the electronic structure of the complex [（η^5-C5Me5）2Zr]2（μ^2, η^2, η^2-N2） is unfavorable for hydrogenation due to the exclusion of side-on dinitrogen in the LUMO＋ 1 molecular orbital as compared with the reactant 1 [（η^5-C5Me4H）2Zr]2（μ2,η^2,η^2-N2）. Besides, the structural feature of the hypothetical intermediate 1′, [（η^5C5Me4H）2Zr]2（μ2,η^2, η^2-N2）-n2, clearly implies the possibility of further hydrogenation. In addition, the distinguishing of vibrational modes of experimental intermediate 2, [（η^5-C5Me4H）2ZrH]2（μ2,η^2,η^2-N2H2）, indicates that the asymmetric stretching of Zr-N and Zr-H leads to dissociation. Moreover, the vibrational intensity of Zr-H is stronger than that of Zr-N. Therefore, it can be predicted that excess hydrogen atmosphere is necessary to ensure the dissociation of Zr-N bonds.

关键词： density functional theory binuclear zirconium complexes electronic structure vibrational properties dinitrogen hydrogenation

OPTIMAL PRICING, PRODUCTION, AND SALES POLICIES FOR NEW PRODUCT UNDER SUPPLY CONSTRAINT

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Journal of Systems Science & Complexity 2014年第2期27卷 289-306页

作者： YAN Xiaoming liu ke WANG Yong School of Computer Science Dongguan University of Technology Institute of Applied Mathematics Academy of Mathematics and Systems Sciences Chinese Academy of Sciences School of Economics and Business Administration Chongqing University

This paper considers a firm that sells a durable product with a given market *** purpose of the firm is to maximize its profit by determining how much capacity to install before the sales horizon, how many products to produce in accordance with the capacity, and how many products to sell by pricing. Appealing to Pontryagin maximum principle in control theory, the authors obtain the closed-forms of all optimal decisions the firm should make. Furthermore, the optimal production rate and optimal sales rate are both equal to the demand rate, which is caused by the optimal pricing policy during the whole horizon, and the optimal pricing path is increasing with the cost of installing a unit of capacity. Furthermore, numerical analysis reveals the visual impression of the relationship of the parameters.

关键词： Capacity constraint inventory new product pricing.

Associations of Daytime Napping with Incident Cardiovascular Diseases and Hypertension in Chinese Adults:A Nationwide Cohort Study

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Biomedical and Environmental Sciences 2022年第1期35卷 22-34页

作者： WANG Lu WANG ke liu Lin Jiong ZHANG Yuan Yuan SHU Hai Nan WANG Kai ZHOU Pei xuan ZHANG Yun Quan Department of Nursing Medical CollegeWuhan University of Science and TechnologyWuhan 430065HubeiChina Department of Epidemiology and Biostatistics School of Public HealthWuhan University of Science and TechnologyWuhan 430065HubeiChina Hubei Province key Laboratory of Occupational Hazard Identification and Control Wuhan University of Science and TechnologyWuhan 430065HubeiChina

Objective This study aimed to examine the associations of daytime napping with incident risks of cardiovascular diseases(CVDs)and hypertension(HTN).Methods Data for napping and CVD outcomes in 25 provinces were collected from baseline(2010)and three waves of follow-up(2012-2017)investigations of the China Family Panel *** frailty models with random intercepts for the surveyed provinces were used to assess the longitudinal effects of daytime napping on CVD and *** Compared with non-nappers,30+min nappers had higher risks of CVD and HTN,while no significant associations were observed amongkers,and participants with longer nighttime sleep(≥7 h/night).Significant effects of daytime napping were observed on rural and northern residents only,highlighting great regional variations in CVD risks associated with napping *** This cohort study revealed strong evidence that long daytime napping(≥30 min)is associated with an increased incidence of cardiovascular events.

关键词： Daytime napping Cardiovascular disease Hypertension Adults Sleep duration

Geometric nonlinear dynamic analysis of curved beams using curved beam element

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Acta Mechanica Sinica 2011年第6期27卷 1023-1033页

作者： ke-Qi Pan Jin-Yang liu School of Naval Architecture Ocean and Civil Engineering Shanghai Jiaotong University 200240 Shanghai China

Instead of using the previous straight beam element to approximate the curved beam,in this paper,a curvilinear coordinate is employed to describe the deformations,and a new curved beam element is proposed to model the curved *** on exact nonlinear strain-displacement relation,virtual work principle is used to derive dynamic equations for a rotating curved beam,with the effects of axial extensibility,shear deformation and rotary inertia taken into *** constant matrices are solved numerically utilizing the Gauss quadrature integration *** and Newton-Raphson iteration methods are adopted to solve the differential equations of the rigid-flexible coupling *** present results are compared with those obtained by commercial programs to validate the present finite *** order to further illustrate the convergence and efficiency characteristics of the present modeling and computation formulation,comparison of the results of the present formulation with those of the ADAMS software are ***,the present results obtained from linear formulation are compared with those from nonlinear formulation,and the special dynamic characteristics of the curved beam are concluded by comparison with those of the straight beam.

关键词： Curved beam element. Geometric nonlinear formulation Rigid-flexible coupling

Reporting and methodological quality of meta-analyses of acupuncture for patients with migraine:A methodological investigation with evidence map

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Journal of Integrative Medicine 2022年第3期20卷 213-220页

作者： Ting-ting Lu Cun-cun Lu Mei-xuan Li Li-xin ke Hui Cai ke-hu Yang Institution of Clinical Research and Evidence-Based Medicine Gansu Provincial HospitalLanzhou 730000Gansu ProvinceChina Evidence-Based Medicine Center School of Basic Medical SciencesLanzhou UniversityLanzhou 730000Gansu ProvinceChina Institute of Basic Research in Clinical Medicine China Academy of Chinese Medical SciencesBeijing 100700China key Laboratory of Evidence-Based Medicine and Knowledge Translation of Gansu Province Lanzhou 730000Gansu ProvinceChina Hepatobiliary and Pancreatic Center the First Affiliated HospitalSun Yat-sen UniversityGuangzhou 510080Guangdong ProvinceChina General Surgery Clinical Medical Center Gansu Provincial HospitalLanzhou 730000Gansu ProvinceChina

Background:Acupuncture has been widely used to relieve migraine-related ***,the findings of previous systematic reviews(SRs)and meta-analyses(MAs)are still not completely *** quality is also unknown,so a comprehensive study is ***:To evaluate the reporting and methodological quality of these MAs concerning acupuncture for migraine,and summarize evidence about the efficacy and safety of acupuncture for *** strategy:Pub Med,Embase,Cochrane Library,China National Knowledge Infrastructure,Chinese Biomedical Databases,Wanfang Data,and VIP databases were searched from inception to September 2020,with a comprehensive search *** criteria:The pairwise MAs of randomized controlled trials(RCTs)concerning migraine treated by acupuncture or acupuncture-based therapies,with a control group that received sham acupuncture,medication,no treatment,or acupuncture at different acupoints were *** extraction and analysis:Two independent investigators screened studies,extracted relevant data,and assessed reporting and methodological quality using Preferred Reporting Items for Systematic Reviews and Meta-Analyses(PRISMA)2009 and A Measurement Tool to Assess Systematic Reviews 2(AMSTAR 2),then all results were *** correlation test was used to evaluate the correlation between reporting and methodological quality ***:A total of 20 MAs were included in this *** included MAs indicated that acupuncture was efficacious and safe in preventing and treating migraine when compared with control *** was a high correlation between reporting and methodological quality scores(rs=0.87,Pkey outcomes,a full list of excluded studies with reasons for exclusion,reporting of RCTs’fundin

关键词： Migraine Acupuncture Systematic review Meta-analysis AMSTAR 2 PRISMA

Outage analysis of ANC in the FDD two-way fading channel with channel estimation error

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The Journal of China Universities of Posts and Telecommunications 2013年第2期20卷 12-18页

作者： GENG xuan liu Feng HE Chen College of Information Engineering Shanghai Maritime University School of Electronic Information and Electrical Engineering Shanghai Jiaotong University

This paper considers a frequency-division duplex （FDD） two-way channel with channel estimation error, where channel gains are independent of each other. It derives the exact closed-form outage probability expressions in the FDD system with analog network coding （ANC） by use of probability theory. To provide more insights, an approximated version for the exact outage probability is also developed in the medium-to-high signal-to-noise ratio （SNR） region. The simulation results show that the derived exact outage probabilities match the results of Monte Carlo simulations in all SNR regions, while the approximated outage probabilities also approach the simulation results when the channel condition is good. It is interesting that ANC in the FDD two-way channel is proved to outperform that of in the time-division duplex （TDD） channel by the computer simulation.

关键词： FDD outage probability two-way channel ANC