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Model Detection and Variable Selection for Varying Coefficient Models with Longitudinal Data

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Acta Mathematica Sinica,English Series 2016年第3期32卷 331-350页

作者： San Ying FENG yu Ping HU liu Gen XUE School of Mathematics and Statistics Zhengzhou University College of Applied Sciences Beijing University of Technology

In this puper, we consider the problem of variabie selection and model detection in varying coefficient models with longitudinM data. We propose a combined penalization procedure to select the significant variables, detect the true structure of the model and estimate the unknown regression coefficients simultaneously. With appropriate selection of the tuning parameters, we show that the proposed procedure is consistent in both variable selection and the separation of varying and constant coefficients, and the penalized estimators have the oracle property. Finite sample performances of the proposed method are illustrated by some simulation studies and the real data analysis.

关键词： Combined penalization longitudinal data model detection variable selection oracle property varying coefficient model

Microstructure, thermal stability and corrosion behavior of ultrasonic shot peened AA7034

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Corrosion Communications 2023年第2期10卷 48-55页

作者： hao liu Jiabo Chen Shuai Wang Bo Du Fahe Cao Qingqing Sun School of Materials Sun Yat-sen University Department of Mechanical and Energy Engineering Southern University of Science and Technology

Microstructure, thermal stability at room temperature and corrosion behavior of ultrasonic shot peened AA7034were investigated in this work. Microstructure modification induced by ultrasonic shot peening was obtained by using OM, SEM, EBSD and XRD, and it was found that a ～200 μm thick gradient surface layer with nanoscale grains on the topmost layer was induced on the peened sample. XRD peaks of the pre-existing aginginduced precipitates, i.e., η′ and η phases, disappeared after peening and did not show up during 52 monthslong natural aging treatment, showing good thermal stability at room temperature. After peening, a significant improvement in intergranular corrosion resistance is evident. Electrochemical characterizations like open circuit potential and electrochemical impedance spectroscopy were conducted on various depths of the peened sample and the results indicated that uniform corrosion rate was largely accelerated by the presence of foreign Ferich contamination, implying that modifications should be made to reduce/avoid the foreign ***, mechanisms of corrosion improvement and good thermal stability of the nanocrystalline surface layer of AA7304 are also discussed.

关键词： 7034 aluminum alloy Surface nanocrystallization Corrosion behavior Thermal stability

A multi-color and white-light emissive cucurbituril/terpyridine/lanthanide supramolecular nanofiber

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Chinese Chemical Letters 2019年第5期30卷 949-952页

作者： Ting Zhang Yaohua liu Bowen Hu Chunhua Zhang Yong Chen yu liu M11T Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage School of Chemistry and Chemical EngineeringHarbin Institute of TechnologyHarbin 150001China College of Chemistry State Key Laboratory of Elemento-Organic ChemistryNankai UniversityTianjin 300071China Collaborative Innovation Center of Chemical Science and Engineering(Tianjin) Tianjin 300072China

Multi-color and white light luminescence materials based on supramolecular assemblies are attractive because of their potential applications in advanced light-emitting ***,a cucurbit[8]urilenhanced lanthanide luminescent supramolecular assembly was constructed in a facile but efficient way using terpyridine imidozalium cations,cucurbit[8]urils and rare earth ions such as Tb3+and Eu3+.Significantly,the resultant fibrous supramolecular assembly,with an average width of 15 nm,could emit remarkable lanthanide luminescence,which was ten times higher than the corresponding terpyridine/Ln3+without cucurbit[8]*** the solid state luminescence of supramolecular assembly could be smartly and easily turned among blue,green,red and white by adjusting the molar ratios between Tb3+and Eu3+.The enhanced white-light emission by supramolecular strategy may provide a new approach for smart and tunable solid luminescent materials.

关键词： Lanthanide luminescence Cucurbituril Host-guest interaction White-light emission Supramolecular chemistry

Doubly Periodic Propagating Wave Patterns of （2＋1）-Dimensional Maccari System

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Communications in Theoretical Physics 2007年第3期47卷 397-402页

作者： HUANG Wen-Hua liu yu-Lu MA Zheng-Yi College of Science Zhejiang Huzhou University Huzhou 313000 China Shanghai Institute of Applied Mathematics and Mechanics Shanghai University Shanghai 200072 China College of Science Zhejiang Lishui University Lishui 323000 China

Using the variable separation approach, we obtain a general exact solution with arbitrary variable separation functions for the （2＋ 1）-dimensional Maccari system. By introducing Jacobi elliptic functions dn and nd in the seed solution, two types of doubly periodic propagating wave patterns are derived. We invest/gate the wave patterns evolution along with the modulus k increasing, many important and interesting properties are revealed.

关键词： Maccari system variable separation method Jacobi elliptic function periodic wave

Novel MSX1 variants identified in families with nonsyndromic oligodontia

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International Journal of Oral Science 2021年第1期13卷 42-51页

作者： Jinglei Zheng Miao yu haochen liu Tao Cai Hailan Feng Yang liu Dong Han Department of Prosthodontics Peking University School and Hospital of Stomatology&National Engineering Laboratory for Digital and Material Technology of Stomatology&Beijing Key Laboratory of Digital StomatologyBeijingChina National Institute of Dental and Craniofacial Research NIHBethesdaMDUSA

The goal of this study was to identify MSX1 gene variants in multiple Chinese families with nonsyndromic oligodontia and analyse the functional influence of these ***-exome sequencing(WES)and Sanger sequencing were performed to identify the causal gene variants in five families with nonsyndromic oligodontia,and a series of bioinformatics databases were used for variant confirmation and functional *** characterization of the members of these families was described,and an in vitro analysis was performed for functional *** novel MSX1 heterozygous variants were identified:three missense variants[c.662A>C(p.Q221P),c.670C>T(p.R224C),and c.809C>T(p.S270L)],one nonsense variant[c.364G>T(p.G122*)],and one frameshift variant[c.277delG(p.A93Rfs*67)].Preliminary in vitro studies demonstrated that the subcellular localization of MSX1 was abnormal with the p.Q221P,p.R224C,p.G122*,and p.A93Rfs*67 variants compared to the wild *** variants(p.Q221P,p.G122*,and p.A93Rfs*67)were classified as pathogenic or likely pathogenic,while p.S270L and p.R224C were of uncertain significance in the current ***,we summarized and analysed the MSX1-related tooth agenesis positions and found that the type and variant locus were not related to the severity of tooth *** results expand the variant spectrum of nonsyndromic oligodontia and provide valuable information for genetic counselling.

关键词： MSX1 variants likely

Cloning and Expression of Low Molecular Weight Glutenin Genes from the Chinese Elite Wheat Cultivar ＂Xiaoyan 54＂

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Journal of Integrative Plant Biology 2006年第2期48卷 212-218页

作者： Xin-yu Wang Kun-Fan liu Wang-Zhen Guo College of Life Sciences Nanjing Agricultural University Nanjing 210095 China Institute of Genetics and Developmental Biology the Chinese Academy of Sciences Beijing 100101 China State Key Laboratory of Crop Genetics ＆ Germplasm Enhancement Nanjing Agricultural University Nanjing 210095 China

The low molecular weight （LMW） glutenln subunlts account for 40% of wheat gluten protein content by mass and these proteins are considered to significantly affect dough quality characteristics. Five new full-length LMW glutenln genes （designated LMW-5, LMW-7, LMW-42, LMW-58, and LMW-34） were isolated from the Chinese elite wheat cultivar ＂Xlaoyan 54＂ by PCR amplification of genomlc DNA using a pair of degenerate primers designed from the conserved sequences of the N- and C-terminal regions of published LMW glutenln genes. Deduced amino acid sequence analysis showed that LMW-5 belongs to the LMW-i type genes and that the other four belong to LMW-m type genes. Sequence comparisons revealed that point mutations occasionally occurred in signal peptide and N-terminus domains and often existed in domain III and domain V. Small insertions and deletions are represented in the repetitive domain. There is a stop codon after amino acid position 110 In the repetitive domain of LMW.34, indicating that It is a pseudogene. The other four genes have complete open reading frames and the putative mature regions of these genes were subcloned Into pET-30a expression vector and successfully expressed in Escherlchla coll. Protein sodium dodecyl sulfate-polyacrylamlde gel electro- phoresls analysis showed that all proteins expressed in E. coil by the four genes could be related to B-group LMW glutenln subunits of wheat.

关键词： low molecular weight glutenin subunit M-type low molecular weight glutenin gene I-type low molecular weightglutenin gene.

CD40-activated B cells are more potent than immature dendritic cells to induce and expand CD41 regulatory T cells

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Cellular & Molecular Immunology 2010年第1期7卷 44-50页

作者： Jian Zheng Yinping liu yu-Lung Lau Wenwei Tu Department of Paediatrics and Adolescent Medicine Li Ka Shing Faculty of MedicineUniversity of Hong KongHong KongChina Joint Research Centre West China Second University HospitalSichuan University and Faculty of MedicineUniversity of Hong KongChengduChina

CD4^(+)regulatory T cells(Tregs)play an important role in maintaining immune tolerance by suppressing pathologic immune responses.,The generation of large numbers of antigen-specific Tregs ex vivo is critical for the development of clinical immunotherapy based on the adoptive transfer of *** CD40-activated B cells(CD40-B)and immature dendritic cells(imDCs)have been used as professional antigen-presenting cells(APCs)to generate antigen-specific ***,the efficiencies of CD40-B and imDCs to generate CD4^(+)Tregs have not been compared directly and the mechanism driving the generation of these Tregs remains largely *** this study,we found that CD40-B exhibited mature phenotypes and were more able to induce and expand CD4^(high)"CD25^(+)Tregs than ***,Tregs induced by CD40-B had greater suppressive capacity than those induced by *** generation of CD4^(high)CD25^(+)Tregs by CD40-B and imDCs is cell-cell contact dependent and partially relies on the expression of human leukocyte antigen(HLA)-DR and CD80/*** in CD4^(high)CD25^(+)Treg generation efficiency were largely explained by the production of endogenous IL-2 by *** results suggest that CD40-B is better able to generate large numbers of antigen-specific Tregs than ***,using CD40-B to generate Tregs may accelerate the clinical use of Treg-based immunotherapy in the treatment of allograft rejection,graft versus host disease(GVHD)and autoimmune diseases.

关键词： B cells immature DC Treg IL-2

Gradient honeycomb metastructure with broadband microwave absorption and effective mechanical resistance

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Nano Materials Science 2024年第4期6卷 456-466页

作者： Dongmeng Li Xia Zheng hao Gu Xiaobo Xuan Bing liu Hongquan Feng Fuheng Zhang Shanghai Radio Equipment Research Institute Shanghai 200438People's Republic of China

Multifunctional metastructure integrated broadband microwave absorption and effective mechanical resistance has attracted much ***,multifunctional performance is limited by the lack of theoretical approaches to integrated ***,a multi-layer impedance gradient honeycomb(MIGH)was designed through theoretical analysis and simulation calculation,and fabricated using 3D printing technique.A theoretical calculation strategy for impedance gradient structure was established based on the electromagnetic parameter equivalent method and the multi-layer finite iterative *** impedance of MIGH was analyzed by the theoretical calculation strategy to resolve the broadband *** loss mechanism of matrix materials and distributions of electric fields,magnetic fields and power loss were analyzed to investigate the absorption *** results indicated that a 15 mm thick designed metastructure can achieve the absorption more than 88.9%in the frequency range of 2-18 ***,equivalent mechanical parameters of MIGH was calculated by integral method according to the Y-shaped *** Element analysis of stress distributions were carried out to predict the deformation *** tests demonstrate that MIGH achieved the compression modulus of 22.89 MPa and flexure modulus of 17.05 *** integration of broadband electromagnetic absorption and effective mechanical resistance was achieved by the proposed design principle and fabrication methodology.

关键词： Multifunctional metastructure Broadband microwave absorption Impedance gradient calculation Mechanical characteristics Finite element analysis

Sand barrier morphological evolution based on time series remote sensing images:a case study of Anhaiao,Pingtan

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Acta Oceanologica Sinica 2020年第12期39卷 121-134页

作者： Heshan Lin Xingguang yu Zhigang yu Yikang Gao Jinyan Xu Aiping Feng Zhijun liu Degang Jiang Fan yu College of Environmental Science and Engineering Ocean University of ChinaQingdao 266100China Island Research Center Ministry of Natural ResourcesPingtan 350400China Third Institute of Oceanography Ministry of Natural ResourcesXiamen 361005China Ministry of Natural Resources Beijing 100812China

The morphological evolution of the sand barrier in the Anhaiao coastal zone of Pingtan from 1996 to 2018 was *** correction was used to refine the location of the coastline.A standard deviation ellipse method was applied to further analyze the movement of the barrier head with the axis and rotation angle.A natural neighbor interpolation(NNI)method was carried out to calculate the terrain of the intertidal area,and the erosion and deposition characteristics were illustrated based on the *** results showed that the northern part of the sand barrier facing the lagoon area was deposited over the whole studied period,while erosion has always occurred in the southern part of the sand barrier facing the open *** erosion and deposition were slightly different on both sides of the barrier head due to hydrodynamic *** middle sand barrier moved 102.60 m away from its original location in 1996,and the end of the barrier moved 65.45 *** head of the sand barrier continued moving 379 m to the ***,the preliminary morphological evolution of the sand barrier corresponding to the distance and direction of movement was detected.

关键词： sand barrier dynamic evolution movement reclamation