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A Modified Residual-based Test for Serial Correlation in Linear Panel Data Models

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Acta Mathematicae Applicatae Sinica 2014年第2期30卷 401-410页

作者： jian-hong wu Wei-hua SU School of Statistics and Mathematics Zhejiang Gongshang University Zhejiang University of Finance and Economics Application of Statistical Science Research Center of Renmin University of China Key Research Institute

This paper suggests a modified serial correlation test for linear panel data models, which is based on the parameter estimates for an artificial autoregression modeled by differencing and centering residual vectors. Specifically, the differencing operator over the time index and the centering operator over the individual index are, respectively, used to eliminate the potential individual effects and time effects so that the resultant serial correlation test is robust to the two potential effects. Clearly, the test is also robust to the potential correlation between the covariates and the random effects. The test is asymptotically chi-squared distributed under the null hypothesis. Power study shows that the test can detect local alternatives distinct at the parametric rate from the null hypothesis. The finite sample properties of the test are investigated by means of Monte Carlo simulation experiments, and a real data example is analyzed for illustration.

关键词： panel data residual-based test serial correlation

Synthesis and Crystal Structure of 2-(4’-Methylphenoxy)-5,8,9-trimethyl-3-phenyl Thieno[3′,2′:5,6]pyrido[4,3-d]pyrimidin-4-(3H)-one Hydrochloride

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Chinese Journal of Structural Chemistry 2006年第5期25卷 577-581页

作者： LIU jian-Chao HE hong-wu DING Ming-wu College of Chemistry Central China Normal University Wuhan 430079 China

The title compound 2-（4＇-methylphenoxy）-5,8,9-trimethyl-3-phenyl thieno[3＇,2＇：5,6] pyrido[4,3-d]pyrimidin-4（3H）-one hydrochloride （C26H23Cl4N3O2S, Mr = 583.33） has been determined by single-crystal X-ray diffraction. The crystal belongs to monoclinic, space group P21/c with a = 14.8442（ 11 ）, b = 11.5131 （8）, c = 17.2010（13） A, β = 113.7250（10）°, V = 2691.3（3） ,A^3, Z = 4, Dc = 1.440 g/cm^3, S = 1.094,μ = 0.547 mm^-1, F（000） = 1200, the final R = 0.0571 and wR = 0.1458. X-ray analysis reveals that the title compound combines with a molecule of dichloromethane by an intramolecular hydrogen bond. The thienopyridine ring is almost coplanar, and the dihedral angle between the thiophene plane and the pyridine plane is 0.6°.

关键词： thieno[3',2':5,6]pyrido[4,3-d]pyrimidin-4(3H)-one,triphenylphosphine iminophosphorane crystal structure

Testing for Serial Correlation in Three-dimensional Panel Data Models

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Acta Mathematicae Applicatae Sinica 2017年第1期33卷 239-250页

作者： jian-hong wu Qing DING Jin-xu QIN College of Mathematics and Science Shanghai Normal University Shanghai 200234 China

This paper studies serial correlation testing for a general three-dimensional panel data model. As a step for hypothesis testing, the robust within estimation of parameter coefficients is investigated, and shown to asymptotically consistent and normal under some mild conditions. A residual-based statistic is then constructed to test for serial correlation in the idiosyncratic errors, which is based on the parameter estimates for an artificial autoregression modeled by centering and differencing residuals. The test can be shown to asymptotically chisquare distributed under the null hypothesis. Power study shows that the test can detect local alternatives distinct at the parametric rate from the null hypothesis. The test needs no distribution assumptions of the error components, and is robust to the misspecification of various specific effects. Monte Carlo simulations are carried out for illustration.

关键词： three-dimensional panel data serial correlation residual-based test

Equivariant Normal Forms for Parameterized Delay Differential Equations with Applications to Bifurcation Theory

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Acta Mathematica Sinica,English Series 2012年第4期28卷 825-856页

作者： Shang jiang GUO Yu Ming CHEN jian hong wu College of Mathematics and Econometrics Hu'nan University Department of Mathematics Wilfrid Laurier University Department of Mathematics and Statistics York University

In this paper, we develop an efficient approach to compute the equivariant normal form of delay differential equations with parameters in the presence of symmetry. We present and justify a process that involves center manifold reduction and normalization preserving the symmetry, and that yields normal forms explicitly in terms of the coefficients of the original system. We observe that the form of the reduced vector field relies only on the information of the linearized system at the critical point and on the inherent symmetry, and the normal forms give critical information about not only the existence but also the stability and direction of bifurcated spatiotemporal patterns. We illustrate our general results by some applications to fold bifurcation, equivariant Hopf bifurcation and Hopf-Hopf interaction, with a detailed case study of additive neurons with delayed feedback.

关键词： Equivariant delay differential equation normal form equilibrium stability bifurcation

A Note on Parameter Estimations of Panel Vector Autoregressive Models with Intercorrelation

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Acta Mathematicae Applicatae Sinica 2009年第2期25卷 177-182页

作者： jian-hong wu Li-xing Zhu Zai-xing Li College of Statistics and Mathematics Zhejiang Gongshang University Hangzhou 310018 China Department of Mathematics Hong Kong Baptist University Hong Kong China Department of Statistics East China Normal University Shanghai 200062 China Department of Mathematics China University of Mining and Technology Beijing 100083 China

This note considers parameter estimation for panel vector autoregressive models with intercorrelation. Conditional least squares estimators are derived and the asymptotic normality is established. A simulation is carr... 详细信息

关键词： Estimation intercorrelation panel Vector autoregression time series

Testing for Random Effects in Linear Mixed Models for Longitudinal Data under Moment Conditions

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Acta Mathematica Sinica,English Series 2010年第3期26卷 497-514页

作者： Zai King LI Li Xing ZHU Ping wu jian hong wu Wang Li XU Department of Mathematics China University of Mining & Technology Beijing 100083 P. R. China Department of Mathematics Hong Kong Baptist University Hong Kong P. R. China School of Finance and Statistics East China Normal University Shanghai 200241 P. R. China College of Statistics and Mathematics Zhejiang Gongshang University Hangzhou 310018 P. R. China School of Statistics Renmin University of China Beijing 100872 P. R. China

In this paper, we consider whether the random effect exists in linear mixed models （LMMs） when only moment conditions are assumed. Based on the estimators of parameters and their asymptotic properties, a Wald-type test is constructed. It is consistent against global alternatives and is sensitive to the local alternatives converging to the null hypothesis at parametric rates, a fastest possibly rate for goodness-of-fit testing. Moreover, a simulation study shows the performance of the test is good. The procedure also applies to a real data.

关键词： consistent estimators asymptotic normality LMMs random effects

Bladder Paraganglioma with a Calculus:A Case Report

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Chinese Journal of Clinical Oncology 2007年第3期4卷 223-225页

作者： jian Wang hong wu Zhou wu jianjun Liu Department of Urology Affiliated Hospita of Guangdong Medical College Zhanjiang Guangdong 524001 China.

A 61-year-old female visited our department reporting intermittent microscopic hematuria. She had slight hypertension of 141/78 mmHg, but there was no family history of hypertension. Computed tomography （CT） of the abdomen showed an isointense lesion within the posterior wall of the urinary bladder with a calculus on the surface （Fig.1）.

关键词： bladder paraganglioma calculus

Human umbilical cord Wharton’s jelly-derived mesenchymal stem cell transplantation could improve diabetic intracavernosal pressure

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Asian Journal of Andrology 2022年第2期24卷 171-175页

作者： jian-hong wu Dong-Ya Wang Lu Sheng Wei-Qing Qian Shu-Jie Xia Qi jiang Department of Urology Shanghai General Hospital of Nanjing Medical UniversityShanghai 200080China Department of Urology Huadong Hospital Affiliated to Fudan UniversityShanghai 200040China Department of Urology Shanghai General HospitalShanghai Jiao Tong University School of MedicineShanghai 200080China

Mesenchymal stem cells(MSCs)secrete various cytokines with angiogenic and neuroprotective *** study aimed to assess the effects of human umbilical cord Wharton’s jelly-derived MSCs(hWJ-MSCs)on diabetes-related intracavernosal pressure(ICP)impairment in ***-MSCs were isolated from human umbilical cord Wharton’s jelly and transplanted into the corpus cavernosum of streptozotocin(STZ)-induced diabetic rats by unilateral *** erectile function was evaluated at 4 weeks,as well as the expression levels of vascular endothelial growth factor(VEGF),basic fibroblast growth factor(bFGF),endothelial nitric oxide synthase(eNOS),and insulin-like growth factor 1(IGF1).STZ-induced diabetic rats showed impaired ICP,which was significantly improved by hWJ-MSC ***,eNOS,IGF1,and bFGF expression levels were higher in hWJ-MSC injection sites than those in control ones in STZ-induced diabetic *** results suggest that hWJ-MSC transplantation might improve diabetic erectile dysfunction through increased production of paracrine growth factors,highlighting a novel potential therapeutic option for erectile dysfunction.

关键词： diabetes endothelial nitric oxide synthase erectile dysfunction mesenchymal stem cells vascular endothelial growth factor

Positions and Spectral Energy Distributions of 41 Star Clusters in M33

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Chinese Journal of Astronomy and Astrophysics 2002年第3期2卷 197-206页

作者： Jun Ma, Xu Zhou, jian-Sheng Chen, hong wu, Zhao-Ji jiang, Sui-jian Xue and Jin ZhuNational Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012 National Astronomical Observatories Chinese Academy of Sciences Beijing 100012

We present accurate positions and multi-color photometry for 41 star clusters detected by Melnick & D'odorico in the nearby spiral galaxy M33 as a part of the BATC Color Survey of the sky in 13 intermediate-band filters from 3800 to 10 000 A. The coordinates of the clusters are found from the HST Guide Star Catalog. By aperture photometry, we obtain the spectral energy distributions of the clusters. Using the relations between the BATC intermediate-band system and UBVRI broadband system, we derive their V magnitudes and B - V colors and find that most of them are blue, which is consistent with previous findings.

关键词： galaxies: individual (M33) - galaxies: evolution - galaxies: star clusters