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SICA for Cox's Proportional Hazards Model with a Diverging Number of Parameters

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Acta Mathematicae Applicatae Sinica 2014年第4期30卷 887-902页

作者： yue-yong shi yong-Xiu CAO Yu-Ling JIAO Yan-Yan LIU School of Mathematics and Statistics Wuhan University

The smooth integration of counting and absolute deviation （SICA） penalized variable selection procedure for high-dimensional linear regression models is proposed by Lv and Fan （2009）. In this article, we extend their idea to Cox＇s proportional hazards （PH） model by using a penalized log partial likelihood with the SICA penalty. The number of the regression coefficients is allowed to grow with the sample size. Based on an approximation to the inverse of the Hessian matrix, the proposed method can be easily carried out with the smoothing quasi-Newton （SQN） algorithm. Under appropriate sparsity conditions, we show that the resulting estimator of the regression coefficients possesses the oracle property. We perform an extensive simulation study to compare our approach with other methods and illustrate it on a well known PBC data for predicting survival from risk factors.

关键词： Cox proportional hazards models penalized partial likelihood diverging parameters oracle prop-erty smoothing quasi-Newton

Additive Hazards Regression under Generalized Case-Cohort Sampling

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Acta Mathematica Sinica,English Series 2014年第2期30卷 251-260页

作者： Ji Chang YU yue yong shi Qing Long YANG Yan Yan LIU School of Mathematics and Statistics Wuhan University School of Statistics and Mathematics Zhongnan University of Economics and Law

Case-cohort design usually requires the disease rate to be low in large cohort study,although it has been extensively used in ***,the disease with high rate is frequently observed in many clinical *** such circumstances,it is desirable to consider a generalized case-cohort design,where only a fraction of cases are *** this article,we propose the inference procedure for the additive hazards regression under the generalized case-cohort *** properties of the proposed estimators for the regression coefcients are *** demonstrate the efectiveness of the generalized case-cohort sampling,we compare it with simple random sampling in terms of asymptotic relative ***,we derive the optimal allocation of the subsamples for the proposed *** fnite sample performance of the proposed method is evaluated through simulation studies.

关键词： Generalized case-cohort pseudo-score function weighted estimating equation optimalallocation

MIMO系统辨识在多机架冷连轧过程中的应用研究

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钢铁研究总院学报 1987年第S1期 83-89页

作者：岳勇石纯一卓兵清华大学副教授

现代控制理论应用于冷连轧过程是一个新的研究课题。本文讨论了MIMO(多输入多输出)线性系统的辨识问题,针对钢铁工业中的多机架冷连轧机实际生产系统,利用实际系统辨识方法和计算机技术,对数学模型的建立问题进行了研究。讨论了建立实... 详细信息

现代控制理论应用于冷连轧过程是一个新的研究课题。本文讨论了MIMO(多输入多输出)线性系统的辨识问题,针对钢铁工业中的多机架冷连轧机实际生产系统,利用实际系统辨识方法和计算机技术,对数学模型的建立问题进行了研究。讨论了建立实用的冷连轧机系统数学模型的方法,建立了两种描述稳态冷连轧过程的动态方程。并用多变量最小二乘法和静态逐步回归方法,分别对描述系统的多变量典范差分方程和扩充的差分方程进行了辨识,得到了描述冷连轧机系统实用的一阶模型。经拟合仿真验证,表明效果较好。以此为基础,建立了一个小型线性系统辨识软件包,为一般系统的辨识研究提供了有效的工具。

关键词：线性模型数学模型机架机座冷连轧机冷轧机差分方程系统辨识系统识别冷连轧过程动态方程一阶 MIMO

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镉对大鼠离体空肠力学特性影响的研究

中国职业医学 2001年第6期28卷 13-15页

作者：陈悦杨永杰石镇霞王强河南大学医学院生理教室河南开封475001

目的　研究镉对大鼠离体空肠力学特性的影响。方法　大鼠 30只 ,各制 2条离体平滑肌条标本 ,共 6 0个 ,分成 3组。分别以盐水、4个剂量组氯化镉液和氯化钙对肌条作灌注 ,用张力感受器测量离体空肠平滑肌的主动张力(PT)、基础张力 (RT)... 详细信息

目的　研究镉对大鼠离体空肠力学特性的影响。方法　大鼠 30只 ,各制 2条离体平滑肌条标本 ,共 6 0个 ,分成 3组。分别以盐水、4个剂量组氯化镉液和氯化钙对肌条作灌注 ,用张力感受器测量离体空肠平滑肌的主动张力(PT)、基础张力 (RT)、主动张力最大收缩速率 (dT/dtmax)和主动张力最大舒张速率 ( -dT/dtmax)、缩短速度 (VCE)、刺激到张力峰值的时程 (TPT)。结果　镉离子浓度在 2 7 5 μmol/L时 ,dT/dtmax和 -dT/dtmax降低 ,RT无明显变化 ,随着镉离子浓度增大 ,观察指标均明显降低 ,当镉离子浓度达 5 5 μmol/L ,有部分标本停止收缩。随着镉离子浓度继续加大 ,停止主动收缩的标本例数亦随之增加。结论　镉离子可直接引起空肠平滑肌收缩力降低。

关键词：镉大鼠空肠肌力学特性动物实验毒性

3D Printing of Tough Hydrogel Scaffolds with Functional Surface Structures for Tissue Regeneration

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Nano-Micro Letters 2025年第2期17卷 18-45页

作者： Ke Yao Gaoying Hong Ximin Yuan Weicheng Kong Pengcheng Xia Yuanrong Li yuewei Chen Nian Liu Jing He Jue shi Zihe Hu Yanyan Zhou Zhijian Xie yong He State Key Laboratory of Fluid Power and Mechatronic Systems School of Mechanical EngineeringZhejiang UniversityHangzhou 310027People’s Republic of China Liangzhu Laboratory Zhejiang UniversityHangzhou 310027People’s Republic of China Key Laboratory of 3D Printing Process and Equipment of Zhejiang Province College of Mechanical EngineeringZhejiang UniversityHangzhou 310027People’s Republic of China Stomatology Hospital School of StomatologyZhejiang University School of MedicineHangzhou 310027People’s Republic of China State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin 150001People’s Republic of China Institute of Digital Medicine Nanjing First HospitalNanjing Medical UniversityNanjing 210006People’s Republic of China

Hydrogel scaffolds have numerous potential applications in the tissue engineering ***,tough hydrogel scaffolds implanted in vivo are seldom reported because it is difficult to balance biocompatibility and high mechanical *** by Chinese ramen,we propose a universal fabricating method(printing-P,training-T,cross-linking-C,PTC&PCT)for tough hydrogel scaffolds to fill this ***,3D printing fabricates a hydrogel scaffold with desired structures(P).Then,the scaffold could have extraordinarily high mechanical properties and functional surface structure by cycle mechanical training with salting-out assistance(T).Finally,the training results are fixed by photo-cross-linking processing(C).The tough gelatin hydrogel scaffolds exhibit excellent tensile strength of 6.66 MPa(622-fold untreated)and have excellent ***,this scaffold possesses functional surface structures from nanometer to micron to millimeter,which can efficiently induce directional cell ***,this strategy can produce bionic human tissue with mechanical properties of 10 kPa-10 MPa by changing the type of salt,and many hydrogels,such as gelatin and silk,could be improved with PTC or PCT *** experiments show that this scaffold can effectively promote the new generation of muscle fibers,blood vessels,and nerves within 4 weeks,prompting the rapid regeneration of large-volume muscle loss injuries.

关键词： 3D printing Tough hydrogel scaffold Functional surface structure Tissue regeneration Biomaterials

Variable selection via generalized SELO-penalized linear regression models

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Applied Mathematics(A Journal of Chinese Universities) 2018年第2期33卷 145-162页

作者： shi yue-yong CAO yong-xiu YU Ji-chang JIAO Yu-ling School of Econoraics and Management China University of GeosciencesWuhan 430074China School of Statistics and Mathematics Zhongnan University of Economics and LawWuhan 430073China Center for Resources and Environmental Economic Research China University of GeosciencesWuhan 430074China

The seamless-L0 （SELO） penalty is a smooth function on [0, ∞） that very closely resembles the L0 penalty, which has been demonstrated theoretically and practically to be effective in nonconvex penalization for variable selection. In this paper, we first generalize SELO to a class of penalties retaining good features of SELO, and then propose variable selection and estimation in linear models using the proposed generalized SELO （GSELO） penalized least squares （PLS） approach. We show that the GSELO-PLS procedure possesses the oracle property and consistently selects the true model under some regularity conditions in the presence of a diverging number of variables. The entire path of GSELO-PLS estimates can be efficiently computed through a smoothing quasi-Newton （SQN） method. A modified BIC coupled with a continuation strategy is developed to select the optimal tuning parameter. Simulation studies and analysis of a clinical data are carried out to evaluate the finite sample performance of the proposed method. In addition, numerical experiments involving simulation studies and analysis of a microarray data are also conducted for GSELO-PLS in the high-dimensional settings.

关键词： continuation coordinate descent BIC LLA oracle property SELO smoothing quasi-Newton

膝关节单髁置换与胫骨高位截骨治疗内翻性膝骨关节炎的比较

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中国组织工程研究 2025年第3期29卷 503-509页

作者：石雷施松陆跃陶然马洪冬南通大学附属医院关节外科江苏省南通市226001

背景:早期膝关节炎可行单髁置换和胫骨高位截骨等方法保膝治疗,但两种保膝手术在术后不同时期膝关节恢复方面是否存在差异仍需进一步探讨。目的:比较单髁置换和胫骨高位截骨治疗膝关节内翻性骨关节炎的疗效及相关并发症等方面的差异,为... 详细信息

背景:早期膝关节炎可行单髁置换和胫骨高位截骨等方法保膝治疗,但两种保膝手术在术后不同时期膝关节恢复方面是否存在差异仍需进一步探讨。目的:比较单髁置换和胫骨高位截骨治疗膝关节内翻性骨关节炎的疗效及相关并发症等方面的差异,为临床决策提供参考。方法:选择2018年9月至2022年9月南通大学附属医院行手术治疗的膝关节内翻性骨关节炎患者103例,其中86例获得1年以上随访,根据手术方法分为单髁置换组(n=49)和胫骨高位截骨组(n=37)。分别对两组患者术前及术后4周、3个月、6个月、1年的膝关节功能、疼痛以及力线纠正情况进行评估,采用美国特种外科医院膝关节评分、美国西安大略大学和麦克马斯特大学功能评分、膝关节外侧间隙变化、关节活动度、本体感觉(位置觉)、术后活动恢复速度等指标综合评判。结果与结论:(1)两组患者术前美国特种外科医院膝关节评分、美国西安大略大学和麦克马斯特大学功能评分、膝关节外侧间室大小均无显著差异;(2)术后4周单髁置换组的美国特种外科医院评分高于胫骨高位截骨组(P<0.05);在术后3,6个月,对比两组患者的改善情况,单髁置换组的美国特种外科医院评分低于胫骨高位截骨组,差异有显著性意义(P<0.05);术后6个月关节活动度屈曲值以及位置觉方面胫骨高位截骨组患者要优于单髁置换组(P<0.05);(3)在膝关节活动恢复速度方面单髁置换组要优于胫骨高位截骨组(P<0.05);(4)然而在术后1年的随访中,两组在美国特种外科医院膝关节评分、伸展方向活动度以及膝关节外侧间隙宽度变化上未见明显差异;(5)所有患者的随访数据均超过1年,且在随访期间均未发现不良并发症;(6)提示采用胫骨高位截骨治疗的内翻性膝骨关节炎患者膝关节功能恢复短期效果优于单髁置换患者,但两种方案治疗内翻性膝骨关节炎的中长期疗效无明显差异。

关键词：膝骨关节炎单髁表面置换胫骨高位截骨膝关节功能并发症

Efficient photocatalytic reduction of CO2 to formate by a molecular noble metal-free system

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Science China Chemistry 2025年第1期 152-156页

作者： Lihua Zhang Lingjing Chen Huatian shi yue Wei Gui Chen Tai-Chu Lau School of Environment and Civil Engineering Research Center for Eco-environmental Engineering Dongguan University of Technology Department of Chemistry and Institute of Molecular Functional Materials City University of Hong Kong

Reducing CO2to carbon-neutral solar fuels can not only alleviate the energy demand but also mitigate the greenhouse *** present,developing an efficient non-noble metal photo/electrocatalytic system for converting CO2to a specific product beyond CO is still a big ***,we report a new cobalt complex bearing 2,2′-bi-1,10-phenanthroline ligand that can photocatalytically reduce CO2to formate （HCOO-）.Turnover number （TON） for HCOO-up to 677 with 99%selectivity can be achieved using organic dyes purpurin as photosensitizer and 1,3-dimethyl-2-phenyl-2,3-dihydro-1H-benzo[d]imidazole （BIH） as sacrificial reductant in a CO2-saturated NMP/TEA （v/v,3:1） solution under visible light *** potential electrolysis at-1.41 V （***/Ag Cl） in the presence of 12 m M Et3NHBF4also produced HCOO-with Faradaic efficiency of 39%.Spectroscopic and electrochemical studies suggest that a[CoI-H]species is the key intermediate for CO2reduction.

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Complement factor Ⅰ knockdown inhibits colon cancer development by affecting Wnt/β-catenin/c-Myc signaling pathway and glycolysis

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World Journal of Gastrointestinal Oncology 2024年第6期16卷 2646-2662页

作者： yong-Jun Du yue Jiang Yan-Mei Hou yong-Bo shi Department of Proctology Hospital of Chengdu University of Traditional Chinese MedicineChengdu 610072Sichuan ProvinceChina School of Clinical Medicine Chengdu University of Traditional Chinese MedicineChengdu 610075Sichuan ProvinceChina Department of Proctology Zigong Hospital of Traditional Chinese MedicineZigong 643000Sichuan ProvinceChina

BACKGROUND Colon cancer(CC)occurrence and progression are considerably influenced by the tumor ***,the exact underlying regulatory mechanisms remain *** To investigate immune infiltration-related differentially expressed genes(DEGs)in CC and specifically explored the role and potential molecular mechanisms of complement factor I(CFI).METHODS Immune infiltration-associated DEGs were screened for CC using *** reverse transcription polymerase chain reaction was used to examine hub DEGs expression in the CC cell *** CFI-knockdown HT29 and HCT116 cell lines were constructed,and the diverse roles of CFI in vitro were assessed using CCK-8,5-ethynyl-2’-deoxyuridine,wound healing,and transwell *** and eosin staining and immunohistochemistry staining were employed to evaluate the influence of CFI on the tumorigenesis of CC xenograft models constructed using BALB/c male nude *** proteins associated with glycolysis and the Wnt pathway were measured using western *** Six key immune infiltration-related DEGs were screened,among which the expression of CFI,complement factor B,lymphoid enhancer binding factor 1,and SRY-related high-mobility-group box 4 was upregulated,whereas that of fatty acid-binding protein 1,and bone morphogenic protein-2 was ***,CFI could be used as a diagnostic biomarker for ***,CFI silencing inhibited CC cell proliferation,migration,invasion,and tumor ***,CFI knockdown downregulated the expression of key glycolysis-related proteins(glucose transporter type 1,hexokinase 2,lactate dehydrogenase A,and pyruvate kinase M2)and the Wnt pathway-related proteins(β-catenin and c-Myc).Further investigation indicated that CFI knockdown inhibited glycolysis in CC by blocking the Wnt/β-catenin/c-Myc *** The findings of the present study demonstrate that CFI plays a crucial role in CC development by influencing g

关键词： Colon cancer Immune infiltration Complement factor I Glycolysis Wnt/β-catenin/c-Myc pathway