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Applied mathematics and mechanics(English Edition) 2021年第6期42卷 819-840页

作者： V.V.THAm H.Q.TRANT T.m.tu National Univensity of Ciwil Engineering Giai Phong Road 55Hai Ba Trung DistrictHanoi 100000 Vietnam

This paper presents an analytical solution for the free vibration behavior of functionally graded carbon nanotube-reinforced composite(FG-CNTRC) doubly curved shallow shells with integrated piezoelectric layers. Here, the linear distribution of electric potential across the thickness of the piezoelectric layer and five different types of carbon nanotube(CNT) distributions through the thickness direction are considered. Based on the four-variable shear deformation refined shell theory, governing equations are obtained by applying Hamilton's principle. Navier's solution for the shell panels with the simply supported boundary condition at all four edges is derived. Several numerical examples validate the accuracy of the presented solution. New parametric studies regarding the effects of different material properties, shell geometric parameters, and electrical boundary conditions on the free vibration responses of the hybrid panels are investigated and discussed in detail.

关键词： free vibration four-variable shear deformation refined theory functionally graded carbon nanotube-reinforced composite(FG-CNTRC) piezoelectric material

On modelling relative risks for longitudinal binomial responses:implications from two dueling paradigms

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General Psychiatry 2023年第2期36卷 143-147页

作者： tuo Lin Rongzhe Zhao Shengjia tu Hao Wu Hui Zhang Xin m tu Division of Biostatistics and Bioinformatics Herbert Wertheim School of Public Health and Human Longevity ScienceUC San DiegoLa JollaCaliforniaUSA College of Environmental Science and Engineering Tongji UniversityShanghaiChina Department of mathematics and Statistics Georgia State UniversityAtlantaGeorgiaUSA Division of Biostatistics Department of Preventive MedicineNorthwestern University Feinberg School of MedicineChicagoIllinoisUSA

Although logistic regression is the most popular for modelling regression relationships with binary responses,many find relative risk(RR),or risk ratio,easier to interpret and prefer to use this measure of risk in regression ***,since Zou published his modified Poisson regression approach for modelling RR for cross-sectional data,his paper has been cited over 7000 times,demonstrating the popularity of this alternative measure of risk in regression analysis involving binary *** longitudinal studies have become increasingly popular in clinical trials and observational studies,it is imperative to extend Zou’s approach for longitudinal *** two most popular approaches for longitudinal data analysis are the generalised linear mixed-effects model(GLmm)and generalised estimating equations(GEE).However,the parametric GLmm cannot be used for the extension within the current context,because Zou’s approach treats the binary response as a Poisson variable,which is at odds with the Bernoulli distribution for the binary *** the other hand,as it imposes no mathematical model on data distributions,the semiparametric GEE is coherent with Zou’s modified Poisson *** this paper,we develop a GEE-based longitudinal model for binary responses to provide inference about RR.

关键词： sectional coherent estimating

On testing proportional odds assumptions for proportional odds models

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General Psychiatry 2023年第3期36卷 214-219页

作者： Anqi Liu Hua He Xin m tu Wan Tang Department of Bostaistis and Data Science Tulane UniversityNew OrleansLouisianaUSA Department of Epidemiology Tulane UniversityNew OrleansLouisianaUSA Division of Biostatistics and Bioinformatics Herbert Wertheim School of Public Health and Human Longevity ScienceUC San DiegoLa JollaCaliforniaUSA

Proportional odds models are commonly used to model ordinal responses,but the proportional odds assumption may not hold in practice,leading to biased *** such as score,Wald and likelihood ratio(LR)have been proposed to evaluate the proportional odds assumption based on models without the *** has proposed an independent binary model-based Wald-type test,and Wolfe and Gould have extended the idea to propose an LR-type *** paper provides a brief review of the Brant and Wolfe-Gould tests for evaluating the proportional odds assumption and evaluates their performance through simulation studies and a real data *** programs are provided in SAS,SPSS and Stata to facilitate the implementation of these tests using standard statistical software *** study highlights the importance of evaluating the proportional odds assumption when using proportional odds models for ordinal *** sample programs provided in this paper make it easy for researchers to apply these tests in their own analyses using standard statistical software packages.

关键词： Gould testing apply

Post-hoc power analysis:a conceptually valid approach for power based on observed study data

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General Psychiatry 2022年第4期35卷 266-272页

作者： Natalie E Quach Kun Yang Ruohui Chen Justin tu manfei Xu Xin m tu Xinlian Zhang Division of Biostatistics and Bioinformatics Herbert Wertheim School of Public Health and Human Longevity ScienceUC San DiegoLa JollaCaliforniaUSA Department of Orthopedics Emory HealthcareEmory UniversityAtlantaGeorgiaUSA Shanghai mental Health Center Shanghai Jiao Tong University School of MedicineShanghaiChina

Power analysis is a key component of planning prospective studies such as clinical ***,some journals in biomedical and psychosocial sciences request power analysis for data already collected and analysed before acceptingmanuscripts for *** have raised concerns about the conceptual basis for such post-hoc power *** recently,Zhang et al showed by using simulation studies that such power analyses do not indicate true power for detecting statistical significance since post-hoc power estimates vary in the range of practical interests and can be very different from the true *** the other hand,journals'request for information about the reliability of statistical findings in a manuscript due to small sample sizes is justified since the sample size plays an important role in the reproducibility of statistical *** problem is the wording of the journals'request,as the current power analysis paradigm is not designed to address journals'concerns about the reliability of the statistical *** this paper,we propose an alternate formulation of power analysis to provide a conceptually valid approach to the journals'wrongly worded but practically significant concern.

关键词： power approach sizes

New solid superbases: potassium nitrate supported on porous materials

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Chinese Science Bulletin 1997年第17期42卷 1493-1494页

作者： Zhu, JH Chun, Y Wang, Y tu, m Chemistry Department Chemistry & Chemical Engineering College Nanjing University Nanjing China

ACCORDING to Tanabe’s definition, all materials possessing the basic strength （H-） over 26.5 are superbases. However, most of superbases known up to now, including CaO and SrO evacuated at 1173 K, K or Na metal supported on KOH/γ-Al2O3, etc. are extremely sensitive to CO2 or H2O in the atmosphere, which limits their application in industrial scale. In or-

关键词： potassium nitrate supported on porous materials New solid superbases

Inconsistency between overall and subgroup analyses

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General Psychiatry 2022年第3期35卷 201-204页

作者： Hongyue Wang Bokai Wang Xin m tu Changyong Feng Departments of Biostatistics&Computational Biology University of RochesterRochesterNew YorkUSA Division of Biostatistics and Bioinformatics Herbert Wertheim School of Public Health and Human Longevity ScienceUC San DiegoLa JollaCaliforniaUSA

Suppose we have a sample of subjects in two treatment *** study the difference of the treatment effects,we can analyse the data using all subjects(overall analysis).We may also divide the subjects into several subgroups based on some covariates of interest(eg,gender),and study the treatment effects within each *** results of these two analyses may be different or even in opposite *** this paper,we give a general sufficient condition of consistency between the overall and subgroup analyses.

关键词： subgroup consistency groups.

The p-value and model specification in statistics

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General Psychiatry 2019年第3期32卷 163-166页

作者： Bokai Wang Zhirou Zhou Hongyue Wang Xin m tu Changyong Feng Departments of Biostatistics and Computational Biology and Anesthesiology University of Rochester Rochester New York USA Family medicine and Public Health University of California San Diego San Diego. California USA Naval Health Research Center San Diego California USA

SUmmARY The p value has been widely used as a way to summarise the significance in data analysis. However, misuse and misinterpretation of the p value is common in practice. Our result shows that if the model specification is wrong, the distribution of the p value may be inappropriate, which makes the decision based on the p value invalid.

关键词： p-value model specification statistics

Ly49 receptors activate angiogenic mouse DBA＋ uterine natural killer cells

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Cellular & molecular Immunology 2014年第5期11卷 467-476页

作者： Patricia DA Lima megan m tu mir munir A Rahim Annie R Peng B Anne Croy Andrew P makrigiannis Department of Biochemistry Microbiologyand Immunology University of Ottawa Ottawa ON KIN 6N5 Canada Biomedical and molecular Sciences Queen's University Kingston ON K7L 3N6 Canada

In humans, specific patterns of killer immunoglobulin-like receptors （KIRs） expressed by uterine natural killer （uNK） cells are linked through HLA-C with pregnancy complications （infertility, recurrent spontaneous abortion, intrauterine growth restriction and preeclampsia）. To identify mechanisms underpinning the associations between NK cell activation and pregnancy success, pregnancies were studied in mice with genetic knockdown （KD） of the mHC-activated Ly49 receptor gene family. ***49KD pregnancies were compared to normal control ***49z29 and C57BL/6 （B6） pregnancies. At mid-pregnancy （gestation day （gd9.5））, overall uNK cell （TCRI^-CD122＋DBA＋DX5- （DBA＋DX5-）） and TCRIβ-CD122＋DBA-DX5＋（DBA-DX5＋）） frequencies in pregnant uterus were similar between genotypes. Ly49KD lowered the normal frequencies of Ly49＋ uNK cells from 90.3% to 47.8% in DBA-DX5＋ and 78.8% to 6.3% in DBA＋DX5- uNK cell subtypes. ***49KD matings frequently resulted in expanded blastocysts that did not implant （subfertility）. ***49KD mice that established pregnancy had gestational lengths and litter sizes similar to controls. ***49KD neonates, however, were heavier than controls. ***49KD implantation sites lagged in early （gd6.5） decidual angiogenesis and were deficient in mid-pregnancy （gd 10.5） spiral arterial remodelling. Ultrastructural analyses revealed that ***49KD uNK cells had impaired granulogenesis, while immunocytochemistry revealed deficient vascular endothelial cell growth factor （VEGFA） production. Perforin and IFNG expression were normal in ***49KD uNK cells. Thus, in normal mouse pregnancies, Ly49 receptor signaling must promote implantation, early decidual angiogenesis and mid-pregnancy vascular remodelling. Disturbances in these functions may underlie the reported genetic associations between human pregnancy complications and the inability of specific conceptus mHCs to engage activating KIR on uNK cells.

关键词： fetal growth deviation granule biogenesis mHC-I receptors uterine natural killer cells vascular endothelialcell growth factor

Post hoc power analysis:is it an informative and meaningful analysis?

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General Psychiatry 2019年第4期32卷 221-225页

作者： Yiran Zhang Rita Hedo Anna Rivera Rudolph Rull Sabrina Richardson Xin m tu Department of Family medicine and Public Health University of California SystemOaklandCaliforniaUSA Naval Health Research Center San DiegoCaliforniaUSA Leidos San DiegoCaliforniaUSA

Power analysis is a key component for planning prospective studies such as clinical trials. However, some journals in biomedical and psychosocial sciences ask for power analysis for data already collected and analysed before accepting manuscripts for publication. In this report, post hoc power analysis for retrospective studies is examined and the informativeness of understanding the power for detecting significant effects of the results analysed, using the same data on which the power analysis is based, is scrutinised. monte Carlo simulation is used to investigate the performance of posthoc power analysis.

关键词： power analysis meaningful analysis

Guidance for use of weights: an analysis of different types of weights and their implications when using SAS PROCs

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General Psychiatry 2019年第1期32卷 49-55页

作者： Sabrina Richardson tuo Lin Yangyi Li Xiaohui Niu manfei Xu Valerie Stander Xin m tu The Henry m.Jackson Foundation for the Advancement of military medicine Inc BethesdaMarylandUnited States military Population Health Naval Health Research CenterSan DiegoCaUnited States Clinical and Translational Research Institute University of California San DiegoSan DiegoCaliforniaUSA School of mathematical and Statistical Sciences Clemson UniversityClemsonSouth CarolinaUSA College of Informatics Huazhong Agriculture UniversityWuhanChina Shanghai mental Health Center Medical CollegeShanghai Jiao Tong UniversityShanghaiChina

SAS and other popular statistical packages provide support for survey data with sampling weights. For example, PROC mEANS and PROC LOGISTIC in SAS have their counterparts PROC SURVEYmEANS and PROC SURVEYLOGISTIC to facilitate analysis of data from complex survey studies. On the other hand, PROC mEANS and many other classic SAS procedures also provide an option for including weights and yield identical point estimates, but different standard errors (SEs), as their corresponding survey procedures. This paper takes an in-depth look at different types of weights and provides guidance on use of different SAS procedures.

关键词： Guidance use of weights analysis