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Life's essential 8 and risk of subclinical atherosclerosis progression: a prospective cohort study

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Journal of Geriatric Cardiology 2024年第7期21卷 751-759页

作者： Shi-Yu ZHOU Fang-Chao LIU Shu-Feng CHEN Jian-Xin LI Jie CAO Ke-Yong HUANG Zheng-Hao TANG Feng-Chao LIANG Dong-Sheng HU Lian-Cheng ZHAO Ying LI Jian-Feng HUANG Xiang-Feng LU Bin LU Dong-Feng GU Department of Epidemiology&Key Laboratory of Cardiovascular Epidemiology State Key Laboratory of Cardiovas-cular DiseaseFuwai HospitalNational Center for Cardiovascular DiseasesChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijingChina school of Public Health and Emergency Management School of Medi-cineSouthern University of Science and TechnologyShenzhenChina Department of Epidemiology and Health stat-istics School of Public HealthZhengzhou UniversityZhengzhouChina Department of Biostatistics and Epidemi-ology School of Public HealthShenzhen University Health Science CenterShenzhenChina Department of Radi-ology State Key Laboratory of Cardiovascular DiseaseFuwai HospitalNational Center for Cardiovascular DiseasesChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijingChina

BACKGROUND Previous studies have demonstrated the benefits of ideal cardiovascular health(CVH) in reducing cardiovascular ***,its role in subclinical atherosclerosis(SA) progression remains *** aim to examine the association of CVH,estimated by the American Heart Association's new Life's Essential 8(LE8),with the progression of *** This prospective cohort study was conducted among 972 asymptomatic Chinese participants and followed up for5.7 *** LE8 score(range,0–100) consisted of blood pressure,lipids,glucose,body mass index,smoking status,diet health,physical activity and sleep health was evaluated in 1998 and 2008–*** of SA was determined by carotid plaque and coronary artery calcification(CAC) in 2008–2009 and 2013–***-binomial regression model was used to estimate the association of LE8 score with SA *** Each 10 points increment in LE8 score was associated with 15.2%(RR:0.848,95% CI:0.797–0.902),17.7%(RR:0.823,95% CI:0.766–0.884) and 12.0%(RR:0.880,95% CI:0.845–0.916) lower risks of carotid plaque,CAC and overall SA progression,*** with participants with non-ideal CVH at both visits,the participants with ideal CVH at both visits had39.1%(RR:0.609,95% CI:0.494–0.752),41.0%(RR:0.590,95% CI:0.456–0.764) and 29.7%(RR:0.703,95% CI:0.598–0.825) lower risks of carotid plaque,CAC and overall SA progression,*** Higher LE8 scores were associated with lower risks of SA ***,long-term maintenance of optimal CVH was more beneficial to prevent SA progression.

关键词： atherosclerosis prospective cardiovascular

The Classification of states for Markov Chain in Random Environments and m-irreducible

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Wuhan University Journal of Natural Sciences 2007年第3期12卷 402-406页

作者： WANG Weigang HU Dihe school of mathematics and statistics Wuhan UniversityWuhan 430072 Hubei China school of mathematics and statistics Yunnan UniversityKunming 650091 Yunnan China

First of all, we introduces the concept of m-irreducible of Markov chain in random environment. Then under the condition of m-irreducible, the relationship of recurrent and positive recurrent between two states is studied. We also give several conditions that can imply a state is recurrent and positive recurrent. And then the period of a state is discussed and we obtained that under the condition of m-irreducible, for any two states in x, they have the same period.

关键词： Markov chain in random environment m-irreducible recurrent stat transient state positive recurrent

Probability density functions of quantum mechanical observable uncertainties

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Communications in Theoretical Physics 2022年第7期74卷 84-98页

作者： Lin Zhang Jinping Huang Jiamei Wang Shao-Ming Fei Institute of mathematics Hangzhou Dianzi UniversityHangzhou 310018China Department of mathematics Anhui University of TechnologyMa Anshan 243032China school of Mathematical Sciences Capital Normal UniversityBeijing 100048China

We study the uncertainties of quantum mechanical observables, quantified by the standard deviation(square root of variance) in Haar-distributed random pure states. We derive analytically the probability density functions(PDFs) of the uncertainties of arbitrary qubit *** on these PDFs, the uncertainty regions of the observables are characterized by the support of the PDFs. The state-independent uncertainty relations are then transformed into the optimization problems over uncertainty regions, which opens a new vista for studying stateindependent uncertainty relations. Our results may be generalized to multiple observable cases in higher dimensional spaces.

关键词： uncertainty of observable probability density function uncertainty region statindependent uncertainty relation

NADARAYA-WATSON ESTIMATORS FOR REFLECTED STOCHASTIC PROCESSES

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Acta Mathematica Scientia 2024年第1期44卷 143-160页

作者：韩月才张丁文 school of mathematics Jilin UniversityChangchun130012China Key Laboratory of Symbolic Computation and Knowledge Engineering of Ministry of Education Jilin UniversityChangchun130012China

We study the Nadaraya-Watson estimators for the drift function of two-sided reflected stochastic differential *** estimates,based on either the continuously observed process or the discretely observed process,are *** certain conditions,we prove the strong consistency and the asymptotic normality of the two *** method is also suitable for one-sided reflected stochastic differential *** results demonstrate that the performance of our estimator is superior to that of the estimator proposed by Cholaquidis et al.(stat Sin,2021,31:29-51).Several real data sets of the currency exchange rate are used to illustrate our proposed methodology.

关键词： reflected stochastic differential equation discretely observed process continuously observed process Nadaraya-Watson estimator asymptotic behavior

Influence of CaxSr1-x(0≤x≤1)Substitution for Zn on Microwave Dielectric Properties of Li2ZnTi3O8 Ceramic as Temperature Stable Materials

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Journal of Wuhan University of Technology(Materials Science) 2020年第4期35卷 686-690页

作者： TIAN Shi LIAO Zelin WANG Heng WANG Weimin school of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China school of Materials Science and Engineering Wuhan Institute of TechnologyWuhan 430205China stat Key Laboratory of Advanced Technology for Materials Synthesisand Processing Wuhan University of TechnologyWuhan 430070China

A temperature stable Li2Zn0.95(SrxCa1-x)0.05Ti3O8(0≤x≤1)ceramics were fabricated using a conventional solid-state route sintered at 1100℃for 4 *** XRD results indicate that the main phase Li2ZnTi3O8 and secondary phase including SrxCa1-xTiO3(0≤x≤1)solid solution and TiO2 co-exist in composite and form a stable composite system when the(CaxSr1-x)(0≤x≤1)substitutes for Zn of Li2ZnTi3O8 *** x is increased from 0 to 1,the relative permittivity(εr)increases from 26.65 to 27.12,and the quality factor(Q×f)increases from 63300 to 66600 *** the increased of x,the temperature coefficient of resonant frequency(τf)increases from 0.27 to 8.23 ppm/℃,and then decreases to 3.51 ppm/℃.On the whole,the Li2Zn0.95(SrxCa1-x)0.05Ti3O8(0≤x≤1)ceramics show excellent comprehensive properties of middleεr=25-27,higher Q×f≥60000 GHz andτf≤±8.5 ppm/℃.

关键词： Li2Zn0.95(SrxCa1-x)0.05Ti3O8(0≤x≤1) microwave dielectric properties temperature stable materials substitution

PSVM: a preference-enhanced SVM model using preference data for classification

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Science China(Information Sciences) 2017年第12期60卷 165-178页

作者： Lerong MA Dandan SONG Lejian LIAO Jingang WANG Engineering Research Center of High Volume Language Information Processing and Cloud Computing Applications School of Computer Science and Technology Beijing Institute of Technology College of mathematics and Computer Science Yan'an University Search Business Department Alibaba Group

Classification is an essential task in data mining, machine learning and pattern recognition *** classification models focus on distinctive samples from different categories. There are fine-grained differences between data instances within a particular category. These differences form the preference information that is essential for human learning, and, in our view, could also be helpful for classification models. In this paper, we propose a preference-enhanced support vector machine(PSVM), that incorporates preference-pair data as a specific type of supplementary information into SVM. Additionally, we propose a two-layer heuristic sampling method to obtain effective preference-pairs, and an extended sequential minimal optimization(SMO)algorithm to fit PSVM. To evaluate our model, we use the task of knowledge base acceleration-cumulative citation recommendation(KBA-CCR) on the TREC-KBA-2012 dataset and seven other datasets from UCI,stat Lib and ***. The experimental results show that our proposed PSVM exhibits high performance with official evaluation metrics.

关键词： preference SVM classification sampling sequential minimal optimization(SMO)

MAXIMUM INFORMATION AND OPTIMUM ESTIMATING FUNCTION

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Chinese Annals of mathematics,Series B 2003年第3期24卷 349-358页

作者： LIN Lu Department of statistics, school of Mathematical Sciences, Nankai University, Tianjin 300071, China. Nankai Univ Sch Math Sci Dept Stat Tianjin 300071 Peoples R China

In order to construct estimating functions in some parametric models, this paper introducestwo classes of information matrices. Some necessary and sufficient conditions for the informationmatrices achieving their upper bounds are given. For the problem of estimating the median,some optimum estimating functions based on the information matrices are acquired. Undersome regularity conditions, an approach to carrying out the best basis function is introduced. Innonlinear regression models, an optimum estimating function based on the information matricesis obtained. Some examples are given to illustrate the results. Finally, the concept of optimumestimating function and the methods of constructing optimum estimating function are developedin more general statistical models.

关键词： Quasi (pseudo) Fisher information Estimating function Quasi score Nonlinear regression model Median regression model

Precise determination of the pole position of the exotic Z_(c)(3900)

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Science China(Physics,Mechanics & Astronomy) 2024年第9期67卷 84-90页

作者： Yun-Hua Chen Meng-Lin Du Feng-Kun Guo school of mathematics and Physics University of Science and Technology BeijingBeijing 100083China school of Physics University of Electronic Science and Technology of ChinaChengdu 611731China CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China school of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Peng Huanwu Collaborative Center for Research and Education Beihang UniversityBeijing 100191China

We perform a unified description of the experimental data of the π^(+)π^(-)and J/ψπ^(±)invariant mass spectra for e^(+)e^(-)→J/ψπ^(+)π^(-)and the D^(0)D^(*-)mass spectrum for e^(+)e^(-)→D^(0)D^(*-)π^(+)at e^(+)e^(-)center-of-mass energies 4.23 and 4.26 *** analysis takes into account open-charm meson loops that contain triangle singularities,the J/ψπ-DD^(*)coupled-channel interaction respecting unitarity,and the strong ππ-KK final state interaction using dispersion *** analysis leads to a precise determination of the Z_(c)(3900)pole with the pole mass and width(3880.7±1.7_(stat)±22.4_(syst))MeV and(35.9±1.4_(stat)±15.3_(syst))MeV,respectively,and hints at that the DD^(*)molecular and non-molecular components are of similar importance in the Z_(c)(3900)formation.

关键词： exotic hadrons dispersion relations final state interaction triangle singularity

Measurement of remanent magnetic moment using a torsion pendulum with single frequency modulation method

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Chinese Physics B 2023年第5期32卷 83-87页

作者：乔敏娜刘鲁华蔡柏松张雅婷王晴岚徐家豪刘祺 school of Aeronautics and Astronautics Sun Yat-sen UniversityGuangzhou 510275China school of Physics and Electronic Engineering Hubei University of Arts and ScienceXiangyang 441053China school of mathematics Physics and Optoelectronic EngineeringHubei University of Automotive TechnologyShiyan 442002China MOE Key Laboratory of TianQin Mission TianQin Research Center for Gravitational Physics&School of Physics and AstronomyFrontiers Science Center for TianQinGravitational Wave Research Center of CNSASun Yat-sen University(Zhuhai Campus)Zhuhai 519082China

In Tian Qin spaceborne gravitational-wave detectors, the stringent requirements on the magnetic cleanliness of the test masses demand the high resolution ground-based characterization measurement of their magnetic properties. Here we present a single frequency modulation method based on a torsion pendulum to measure the remanent magnetic moment mr of 1.1 kg dummy copper test mass, and the measurement result is(6.45 ± 0.04(stat) ± 0.07(syst)) × 10^(-8)A · m^(2). The measurement precision of the mr is about 0.9 n A · m^(2), well below the present measurement requirement of Tian Qin. The method is particularly useful for measuring extremely low magnetic properties of the materials for use in the construction of space-borne gravitational wave detection and other precision scientific apparatus.

关键词： remanent magnetic moment torsion pendulum single frequency modulation method