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Projection-based Consistent Test for Linear Regression Model with Missing Response and Covariates

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Acta Mathematicae Applicatae Sinica 2020年第4期36卷 917-935页

作者： Su-jin ZHENG Si-yu GAO zhi-hua sun China Institute for Actuarial Science/School of Insurance Central University of Finance and EconomicsBeijing 100081China School of Mat hematic Sciences University of Chinese Academy of SciencesBeijing 100049China Key Laboratory of Big Data Mining and Knowledge Management of Chinese Academy of Sciences Beijing 100049China

In recent years,there has been a large amount of literature on missing *** of them focus on situations where there is only missingness in response or *** this paper,we consider the adequacy check for the linear regression model with the response and covariates missing *** apply model adjustment and inverse probability weighting methods to deal with the missingness of response and covariate,*** order to avoid the curse of dimension,we propose an empirical process test with the linear indicator weighting *** asymptotic properties of the proposed test under the null,local and global alternative hypothe tical models are rigorously investigated.A consisten t wild boot strap method is developed to approximate the critical ***,simulation studies and real data analysis are performed to show that the proposed method performed well.

关键词： consistency linear indicator weighting function empirical process missing response and covariates projection

Variable Selection of Generalized Regression Models Based on Maximum Rank Correlation

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Acta Mathematicae Applicatae Sinica 2014年第3期30卷 833-844页

作者： Peng-jie DAI Qing-zhao ZHANG zhi-hua sun School of Business Renmin University of China Department of Mathematics University of Chinese Academy of Sciences

In this paper, we investigate the variable selection problem of the generalized regression models. To estimate the regression parameter, a procedure combining the rank correlation method and the adaptive lasso technique is developed, which is proved to have oracle properties. A modified IMO （iterative marginal optimization） algorithm which directly aims to maximize the penalized rank correlation function is proposed. The effects of the estimating procedure are illustrated by simulation studies.

关键词： maximum rank correlation estimation adaptive LASSO oracle properties generalized regression models.

Semiparametric Analysis of Longitudinal Data with Informative Observation Times

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Acta Mathematicae Applicatae Sinica 2011年第1期27卷 29-42页

作者： Liu-quan sun Xiao-yun Mu zhi-hua sun Xing-wei Tong Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China School of mathematical Sciences Beijing Normal University Beijing 100875 China

In many longitudinal studies, observation times as well as censoring times may be correlated with longitudinal responses. This paper considers a multiplicative random effects model for the longitudinal response where these correlations may exist and a joint modeling approach is proposed via a shared latent variable. For inference about regression parameters, estimating equation approaches are developed and asymptotic properties of the proposed estimators are established. The finite sample behavior of the methods is examined through simulation studies and an application to a data set from a bladder cancer study is provided for illustration.

关键词： Estimating equations Informative observation times Joint modeling Latent variables,Longitudinal data

A new sesquiterpene from Caragana intermediia

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Chinese Chemical Letters 2007年第11期18卷 1379-1382页

作者： zhi hua sun Chang Qi Hu Jin Yi Wang School of Pharmacy Fudan University Shanghai 200032 China College of Science Northwest A＆F University Yangling 712100 China

A new alloaromadendrane-type sesquiterpene, （-）-alloaromadendrane-3β,9β-diol （1）, has been isolated from the aerial part of Caragana intermediia. The structure of （-）-alloaromadendrane-3β,9β-diol （1） was established by spectroscopic methods, including X-ray analysis that provided its relative stereochemistry. Bioassay showed that （-）-alloaromadendrane-3β,9β-diol （1） possesses anti-pyricularia oryzae P-2b activity with MIC value of 10 μg/m-L.

关键词： Caragana intermediia Leguminosae Sesquitetpene (-)-Alloaromadendrane-3β,9β-diol

Quasi-likelihood estimation of average treatment effects based on model information

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Science China Mathematics 2007年第1期50卷 1-12页

作者： zhi-hua sun Academy of Mathematics and Systems Science, Chinese Academy of Science, Beijing 100080, China Academy of Mathematics and Systems Science Chinese Academy of Science Beijing China

In this paper, the estimation of average treatment effects is considered when we have the model information of the conditional mean and conditional variance for the responses given the covariates. The quasi-likelihood method adapted to treatment effects data is developed to estimate the parameters in the conditional mean and conditional variance models. Based on the model information, we define three estimators by imputation, regression and inverse probability weighted methods. All the estimators are shown asymptotically normal. Our simulation results show that by using the model information, the substantial efficiency gains are obtained which are comparable with the existing estimators.

关键词： average treatment effects inverse probability weighted quasi-likelihood unconfounded assignment treatment model information 62G18

CMOS direct conversion X-ray detector coupled with fluorinated liquid

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Nuclear Science and Techniques 2025年第1期36卷 59-68页

作者： Shi-hua Liu Chao-Song Gao Xin Zhang Xiang-Ming sun Meng Wu zhi-Hui Han Tong Wan Yong-Shuai Ge Key Laboratory of Quark&Lepton Physics(MOE) Central China Normal UniversityWuhan 430079China Guizhou Education University Guiyang 550018China Research Center for Medical Artificial Intelligence Chinese Academy of SciencesShenzhen Institutes of Advanced TechnologyShenzhen 518055China

X-ray detectors show potential applications in medical imaging,materials science,and nuclear *** achieve high detection efficiency and spatial resolution,many conventional semiconductor materials,such as amorphous selenium,cadmium telluride zinc,and perovskites,have been utilized in direct conversion X-ray ***,these semiconductor materials are susceptible to temperature-induced performance degradation,crystallization,delamination,uneven lattice growth,radiation damage,and high dark *** study explores a new approach by coupling an FC40 electronic fluorinated liquid with a specialized high-resolution and high-readout-speed complementary metal-oxide-semiconductor(CMOS)pixel array,specifically the Topmetal II−chip,to fabricate a direct conversion X-ray *** fluorinated liquid FC40(molecular formula:C_(21)F_(48)N_(2))is an electronic medium that is minimally affected by temperature and displays no issues with uniform *** exhibits a low dark current and minimal radiation damage and enables customizable thickness in X-ray *** addresses the limitations inherent in conventional semiconductor-based *** this study,simple X-ray detector imaging tests were conducted,demonstrating the excellent coupling capability between FC40 electronic fluorinated liquid and CMOS chips by the X-ray detector.A spatial resolution of 4.0 lp/mm was measured using a striped line par card,and a relatively clear image of a cockroach was displayed in the digital radiography imaging *** test results indicated the feasibility of fabricating an X-ray detector by combining FC40 electronic fluorinated liquid and CMOS *** to the absence of issues related to chip-material coupling,a high spatial resolution could be achieved by reducing the chip pixel *** method presents a new avenue for studies on novel liquid-based direct conversion X-ray detectors.

关键词： FC40 electronic fluorinated liquid CMOS pixel chip X-ray detector Spatial resolution

CAF-derived exosome-miR-3124-5p promotes malignant biological processes in NSCLC via the TOLLIP/TLR4-MyD88-NF-κB pathway

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Oncology Research 2025年第1期33卷 133-148页

作者： TAO sun QINGhua SONG hua LIU Department of Respiratory and Critical Care Medicine Affiliated Hospital of Nantong UniversityMedical School of Nantong UniversityNantong226001China Department of Emergency The People’s Hospital of RugaoNantong226500China Department of Haematology The People’s Hospital of RugaoNantong226500China

Background:Lung cancer is a life-threatening disease that occurs worldwide,but is especially common in *** crucial role of the tumour microenvironment(TME)in non-small cell lung cancer(NSCLC)has attracted recent ***-associated fibroblasts(CAFs)are the main factors that contribute to the TME function,and CAF exosomes are closely linked to ***:The expression levels of miR-3124-5p and Toll-interacting protein(TOLLIP)were analysed by bioinformatics prediction combined with RT-qPCR/Western Blot *** were isolated and identified from clinical NSCLC *** electron microscopy and Western Blot were used to identify exosomes from these *** in proliferation(CCK-8 and clone formation),migration(wound healing),and invasion(transwell)of NSCLC cells were *** Luciferase reporter test was applied to clarify the binding of miR-3124-5p to *** TOLLIP/TLR4/MyD88/NF-κB pathway proteins were determined using Western blot ***:MiR-3124-5p is overexpressed in clinical tissues and cells of ***-3124-5p was dramatically enriched in CAF-derived *** experiments revealed that CAFs delivered miR-3124-5p into NSCLC cells via exosomes,stimulating cancer cell ***-3124-5p acted as a sponge to negatively regulate TOLLIP expression,which activated the TLR4/MyD88/NF-κB axis to promote the occurrence and development of *** salvage tests were performed to determine whether CAF-exosome-derived miR-3124-5p plays a pro-cancer role in NSCLC by affecting the TOLLIP signalling ***:These results provide an interesting direction for the diagnosis and therapy of NSCLC.

关键词： Non-small cell lung cancer(NSCLC) Cancer-associated fibroblasts(CAFs) Exosomes miR-3124-5p Toll-interacting protein(TOLLIP)

Synergistic mechanism of metal ions and sodium N-oleoylsarcosinate on flotation separation of lepidolite from feldspar

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中国有色金属学报 2025年第1期35卷 296-312页

作者： Guo-yuan XIANG Rui-hua FAN Wen-tao ZHU Wei sun Ren-ji ZHENG zhi-yong GAO School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083China Key Laboratory of Hunan Province for Clean and Efficient Utilization of Strategic Calcium-containing Mineral Resources Central South UniversityChangsha 410083China Hunan International Joint Research Centre for Efficient and Clean Utilization of Critical Metal Mineral Resources Central South UniversityChangsha 410083China Engineering Research Center of Ministry of Education for Carbon Emission Reduction in Metal Resource Exploitation and Utilization Central South UniversityChangsha 410083China

The combined reagents of sodium N-oleoylsarcosinate(SNOS)with metal ions(Ca(Ⅱ),Mg(Ⅱ),Cu(Ⅱ),and Pb(Ⅱ))was employed to facilitate the separation of lepidolite from *** synergistic interaction mechanism of this combined reagent was systematically investigated via contact angle measurements,AFM,FTIR,species distribution calculations,and DFT *** results suggested that Ca(Ⅱ)exhibited the best selectivity for activating lepidolite *** was chemically adsorbed on the Ca(Ⅱ)-activated lepidolite surface with an adsorption energy of−1248.91 kJ/mol while a lower adsorption energy of−598.84 kJ/mol of SNOS on Ca(Ⅱ)-activated feldspar was ***,this combination of SNOS and Ca(Ⅱ)is a promising reagent scheme for the efficient recovery of lithium from aluminosilicate ore.

关键词： flotation lepidolite feldspar sodium N-oleoylsarcosinate metal ions

A cationic radical lanthanide organic tetrahedron with remarkable coordination enhanced radical stability

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Chinese Chemical Letters 2025年第02期36卷 568-573页

作者： Zhengzhong Zhu Shaojun Hu zhi Liu Lipeng Zhou Chongbin Tian Qingfu sun State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences University of the Chinese Academy of Sciences

Rare–earth supramolecular compounds, such as lanthanide organic polyhedrons（LOPs）, are of particular interest due to their many possible applications in various fields. Here we report the first syntheses of Ln4(L·+)4–type(Ln, lanthanides; L·+, radical ligand) radical–bridged lanthanide organic tetrahedrons by self–assembly of face–capping triphenylamine（TPA）–cored radical ligand with different lanthanide *** coordination enhanced radical stability has been observed, with half–life times(t1/2) for L1·+,La4(L1·+)4, Eu4(L1·+)4, Gd4(L1·+)4, Tb4(L1·+)4and Lu4(L1·+)4estimated to be 53 min, 482 min, 624 min,1248 min, 822 min and 347 min, respectively. The TPA radical in Ln4(L1·+)4containing paramagnetic Ln ions（Ln = EuⅢ, GdⅢand TbⅢ） is observed to be more stable than that in Ln4(L1·+)4（Ln = LaⅢand LuⅢ）constructed by diamagnetic Ln ions. This difference in radical stability is possibly due to the magnetic interactions between paramagnetic LnⅢions and L1·+ligands, as confirmed by electron paramagnetic resonance（EPR） in La4（L）4(L = L1and L1·+) and Tb4（L）4(L = L1and L1·+), and magnetic susceptibility measurements in Tb·4（L）4(L = L1and L1·+). Our study reveals the coordination of radical ligands with lanthanide ions can improve the radical stability, which is crucial for their applications.

关键词： Enhanced stability Lanthanide organic polyhedrons Radical Self–assembly Supramolecular chemistry