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Asymptotic Inference in the Random Coefficient Autoregressive Model with Time-functional Variance Noises

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 320-346页

作者： En-wen ZHU Zi-wei DENG Han-jun ZHANG Jun CAO Xiao-hui LIU Department of Mathematics and Statistics Changsha University of Science and TechnologyChangsha 410114China School of Mathematics and Computational Science Xiangtan UniversityXiangtan 411105China School of Statistics and Data Science and Key Laboratory of Data Science in Finance and EconomicsJiangxi University of Finance and EconomicsNanchang 330013China

This paper considers the random coefficient autoregressive model with time-functional variance noises,hereafter the RCA-TFV *** first establish the consistency and asymptotic normality of the conditional least squares estimator for the constant *** semiparametric least squares estimator for the variance of the random coefficient and the nonparametric estimator for the variance function are constructed,and their asymptotic results are reported.A simulation study is presented along with an analysis of real data to assess the performance of our method in finite samples.

关键词： random coefficient autoregressive model time-functional variance conditional least squares semiparametric least squares

Asymptotic Inferences in the Random Coefficient Autoregressive Model with Time-functional Variance Noises

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Acta Mathematicae Applicatae Sinica 2024年

作者： En-wen ZHU Zi-wei DENG Han-jun ZHANG Jun CAO Xiao-hui LIU Department of Mathematics and Statistics Changsha University of Science and Technology School of Statistics and Data Science and Key Laboratory of Data Science in Finance and Economics Jiangxi University of Finance and Economics School of Mathematics and Computational Science Xiangtan University

This paper considers the random coefficient autoregressive model with time-functional variance noises, hereafter the RCA-TFV model. We first establish the consistency and asymptotic normality of the conditional least squares estimator for the constant coefficient. The semiparametric least squares estimator for the variance of the random coefficient and the nonparametric estimator for the variance function are constructed,and their asymptotic results are reported. A simulation study is presented along with an analysis of real data to assess the performance of our method in finite samples.

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SARS-CoV-2 spike-specific TFH cells exhibit unique responses in infected and vaccinated individuals

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Signal Transduction and Targeted Therapy 2023年第11期8卷 5338-5352页

作者： Rongzhang He Xingyu Zheng Jian Zhang Bo Liu Qijie Wang Qian Wu Ziyan Liur Fangfang Chang Yabin Hu Ting Xie Yongchen Liu Jun Chen Jing Yang Shishan Teng Rui Lu Dong Pan You Wang Liting Peng Weijin Huang Velislava Terzieva Wenpei Liu Youchun Wang Yi-Ping Li Xiaowang Qu College of Basic Medical Sciences Hengyang Medical SchoolUniversity of South China&MOE Key Lab of Rare Pediatric Diseases421001 HengyangChina Translational Medicine Institute The First People's Hospital of ChenzhouHengyang Medical SchoolUniversity of South China423000 ChenzhouChina The Central Hospital of Shaoyang 422000 ShaoyangChina Institute of Human Virology Zhongshan School of Medicineand Key Laboratory of Tropical Disease Control of Ministry of EducationSun Yat-sen University501180 GuangzhouChina School of Public Health University of South China421001 HengyangChina National Institutes for Food and Drug Control Key Laboratory of the Ministry of Health for Research on Quality and Standardization of Biotech ProductsKey Laboratory of Biological Product Quality Research and Evaluation of National Medical Products Administration102629 BejingChina Laboratory of OMICs Technologies Institute of Biology and Immunology of Reproduction"Acad.Kiril Bratanov"BulgarianAcademyof SciencesSofia 1113Bulgaria

Long-term humoral immunity to SARS-CoV-2 is essential for preventing reinfection. The production of neutralizing antibody (nAb)and B cell differentiation are tightly regulated by T follicular help (T_(FH)) cells. However, the longevity and functional role of T_(FH) cellsubsets in COVID-19 convalescents and vaccine recipients remain poorly defined. Here, we show that SARS-CoV-2 infection andinactivated vaccine elicited both spike-specific CXCR3^(+) T_(FH) cell and CXCR3^(-) T_(FH) cell responses, which showed distinct responsepatterns. Spike- specific CXCR3^(+) T_(FH) cells exhibit a dominant and more durable response than CXCR3^(-) T_(FH) cells that positivelycorrelated with antibody responses. A third booster dose preferentially expands the spike-specific CXCR3^(+) T_(FH) cell subset inducedby two doses of inactivated vaccine, contributing to antibody maturation and potency. Functionally, spike-specific CXCR3^(+) T_(FH) cellshave a greater ability to induce spike-specific antibody secreting cells (ASCs) differentiation compared to spike-specific CXCR3^(-) T_(FH)cells. In conclusion, the persistent and functional role of spike-specific CXCR3^(+) T_(FH) cells following SARS-CoV-2 infection andvaccination may play an important role in antibody maintenance and recall response, thereby conferring long-term protection. Thefindings from this study will inform the development of SARS-CoV-2 vaccines aiming to induce long-term protective immunememory.

关键词： vaccine doses protective

Toward an optimized strategy of using various airway mucus clearance techniques to treat critically ill COVID-19 patients

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BIOCELL 2022年第4期46卷 855-871页

作者： MINGZHI LUO KAI NI YAN SUN JIA GUO KANG WEN LINHONG DENG Changzhou Key Laboratory of Respiratory Medical Engineering Institute of Biomedical Engineering and Health SciencesChangzhou UniversityChangzhou213164China

Coronavirus disease 2019(COVID-19)caused by acute respiratory syndrome coronavirus 2(SARS-Cov-2)is still threatening the human life and society throughout the *** those critically ill patients,mechanical ventilation(MV)is essential to provide life support during ***,both the virus infection and MV disrupt the balance between secretion and elimination of airway mucus and lead to mucus accumulation in the *** examination verified that the lungs in patients died of COVID-19 are indeed filled with sticky mucus,suggesting a great need to improve airway mucus clearance in critically ill COVID-19 ***,it may be helpful to comprehensively review the current understanding regarding the changes of biochemical and rheological features of airway mucus associated with the disease,as well as the physiological principles and algorithm to decide airway clearance techniques suitable for the critically ill COVID-19 *** on these considerations,optimized strategies may be developed to eliminate the airway mucus accumulated in the airways of critically ill COVID-19 patients.

关键词： COVID-19 Airway mucus Rheology Mechanical force Airway clearance techniques

AN EXPLICIT MULTISTEP SCHEME FOR MEAN-FIELD FORWARD-BACKWARD STOCHASTIC DIFFERENTIAL EQUATIONS

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Journal of Computational Mathematics 2022年第4期40卷 517-540页

作者： Yabing Sun Jie Yang Weidong Zhao Tao Zhou School of Mathematics Shandong UniversityJinan 250100ChinaCollege of ScienceNational University of Defense TechnologyChangsha 410073China School of Mathematics and Statistics Shandong UniversityWeihai 264209China School of Mathematics and Finance Institute Shandong UniversityJinan 250100China LSEC Institute of Computational MathematicsAcademy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China

This is one of our series works on numerical methods for mean-field forward backward stochastic differential equations(MFBSDEs).In this work,we propose an explicit multistep scheme for MFBSDEs which is easy to implement,and is of high order rate of *** error estimates of the proposed multistep scheme are *** experiments are carried out to show the efficiency and accuracy of the proposed scheme.

关键词： Mean-field forward backward stochastic differential equations Explicit multistep scheme Error estimates

Asymptotic Behavior of Forced Nonlinear Delay Differential Equations with Impulses

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Acta Mathematica Sinica,English Series 2000年第4期16卷 565-572页

作者： Jiaowan Luo Institute of Sciences. Changsha Railway University. Changsha 410075. P. R. China Jianhua Shen Department of Mathematics. hunan Normal University. Changsha 410081. P. R. China Institute of Sciences Changsha Railway University Changsha 410075 P. R. China Department of Mathematics Hunan Normal University Changsha 410081 P. R. China

The purpose of this paper is to investigate the asymptotic behavior of solutions of the forced nonlinear delay differential equations with impulses x’(t)+sum from i=1 to n(p_i(t)f(x(t-т_i))=h(t)). t≠t_k, x(t_k^+)-x(t_k)=b_kx(t_k). Our results. which hold for linear and nonlinear equations, forced and unforced equations, impulsive and nonimpulsive equations. improve and generalize the known results recently obtained in [8].

关键词： Asymptotic behavior Delay differential equation Impulsive perturbation

Lorentz transformation of three dimensional gravitational wave tensor

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Communications in Theoretical Physics 2023年第4期75卷 70-77页

作者： Xiaokai He Zhoujian Cao School of Mathematics and Statistics Hunan First Normal UniversityChangsha 410205China Institute for Frontiers in Astronomy and Astrophysics Beijing Normal UniversityBeijing 102206China Department of Astronomy Beijing Normal UniversityBeijing 100875China School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUCASHangzhou 310024China

Recently there has been more and more interest in the gravitational wave(GW) of moving sources. This paper introduces a Lorentz transformation problem of GWs. Although the BondiMetzner-Sachs(BMS) theory has in principle already included the Lorentz transformation of GWs, the transformation of the three-dimensional GW tensor has not been explicitly calculated before. Within four-dimensional spacetime, GWs have the properties of ‘boost weight zero’ and‘spin weight 2’. This fact makes the Lorentz transformation of GWs difficult to understand. In the current paper, we adopt the traditional three-dimensional tensor description of a GW. Such a transverse-traceless tensor describes the GW freedom directly. We derive the explicit Lorentz transformation of the GW tensor. The transformation is similar to the Lorentz transformation for an electric field vector and a magnetic field vector which are three-dimensional vectors. Based on the deduced Lorentz transformation of the GW three-dimensional tensor, we can construct the gravitational waveform of a moving source with high speed if only the waveform of the corresponding rest waveform is given.

关键词： gravitational wave lorentz transformation waveform template

Oscillations and Collapses of Proto-Neutron Stars

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Chinese Physics Letters 2009年第1期26卷 32-35页

作者：吕君丽 Wan Mew-Bing Department of Physics Hunan Normal University Changsha 410081 Department of Physics Washington University One Brookings Drive St. Louis MO 63130 USA

We examine the oscillation and collapse of a relativistic star, e.g., a proto-neutron star, with an equation of state （EOS） which is Mowly changing as driven by, e.g., losing of thermal energy through radiations. We find that the frequency of the fundamental mode of oscillation （radial） will gradually increase then abruptly drop to zero when the star gets close to the point of instability. We also find that for a wide range of configurations on the unstable branch of equilibrium configurations, the collapse is dominated by one unstable mode.

关键词： RELATIVISTIC STELLAR MODELS APPROACHING SCHWARZSCHILD LIMIT DYNAMICAL INSTABILITY GENERAL RELATIVITY ANALYTIC ANALYSIS RADIAL PULSATION

Syntheses and Structures of Three Hybrid Materials Using Vanadium Polyoxoanions and Macrocyclic Copper Complex as Building Blocks

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Chinese Journal of Structural Chemistry 2017年第1期36卷 135-142页

作者：欧光川廖阳向岳峰袁先友李治章 Key Laboratory of Comprehensive Utilization of Advantage Plants Resources in hunan South/Department of Biology and Chemistry Hunan University of Science and Engineering

The reactions of the four-coordinated macrocyclic copper complex [CuL]（ClO4）2（L = 1,4,8,11-tetraazacyclotetradecane） with NH4VO3 under different conditions gave three inorganic-organic hybrid materials of [CuL][VO3]2·2.33H2O（1）, [CuL]3[V（10）O（28）]·8H2O（2） and [Cu L]3[V6O（18）]·8H2O（3）. Single-crystal X-ray diffraction analyses reveal that three diverse vanadium polyoxoanions, [V6O（18）]6- ring, [V（10）O（28）]6- cluster, and [V（12）O（35）]^10- ring, were isolated from the same reactant NH4VO3 under different conditions. The [CuL]^2＋ bridges the [V10O28]6- clusters to form a two-dimensional sheet in 2, and link the [V6O（18）]^6- rings in 1 and [V（12）O（35）]^10- rings in 3 into three-dimensional frameworks, respectively.

关键词： polyoxovanadate macrocyclic copper(Ⅱ) complexes hybrid materials