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Challenges of Big Data analysis

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National Science Review 2014年第2期1卷 293-314页

作者： Jianqing Fan fang Han Han Liu Department of Operations Research and Financial Engineering Princeton University Department of Biostatistics Johns Hopkins University

Big Data bring new opportunities to modern society and challenges to data scientists. On the one hand,Big Data hold great promises for discovering subtle population paterns and heterogeneities that are not possible with small-scale data. On the other hand, the massive sample size and high dimensionality of Big Data introduce unique computational and statistical challenges, including scalability and storage botleneck, noise accumulation, spurious correlation, incidental endogeneity and measurement errors.hese challenges are distinguished and require new computational and statistical paradigm. his paper gives overviews on the salient features of Big Data and how these features impact on paradigm change on statistical and computational methods as well as computing architectures. We also provide various new perspectives on the Big Data analysis and computation. In particular, we emphasize on the viability of the sparsest solution in high-conidence set and point out that exogenous assumptions in most statistical methods for Big Data cannot be validated due to incidental endogeneity. hey can lead to wrong statistical inferences and consequently wrong scientiic conclusions.

关键词： Big Data noise accumulation spurious correlation incidental endogeneity data storage scalability

A Macro-Mechanical Study for Capturing the Dynamic Behaviors of a Rate-Dependent Elastomer and Clarifying the Energy Dissipation Mechanisms at Various St rain Rates

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Acta Mechanica Solida Sinica 2022年第2期35卷 228-238页

作者： Shahzad Fateh Ali Jitang fan jianqing Feng Xiangquan Wei State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China Aerospace System Engineering shanghai Shanghai 201109China

A strain-rate-sensitive polyurethane elastomer is numerically investigated to reveal improved impact characteristics and analyze the concerned rate dependencies and dynamic energy dissipation features.A physical constitutive model in view of amorphous molecular struc-ture of the elastomer is proposed by relating the macro-mechanical behaviors to micro-structural changes through molecular transitions and flow activations.Two distinct relaxation processes are considered because of entangled molecular net works,with each possessing a unique activation energy.Through calibration with experimental data,finite element simulations based on the model are conducted.Related to the loading rate,the structural entropy of molecular chain entanglements,rate-dependent yielding,plateau flow and densification are well predicted by the model.The investigations are extended further regarding the material recoverability and accordingly,strain energy absorptions are illustrated.A power law function is proposed for designing the energy absorption relation to the applied loading rate.Finally,the inherent mechanisms causing the dynamic energy absorptions are analyzed with notable clarifications of post-experimental observations obtained via scanning elec Iron microscopy.

关键词： Elastomer Constitutive model Energy absorption Ratedependent Scanning electron microscopy

Nonmuscle myosin IIA promotes the internalization of influenza A virus and regulates viral polymerase activity through interacting with nucleoprotein in human pulmonary cells

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Virologica Sinica 2023年第1期38卷 128-141页

作者： Jian Chen Jian Liu Zhilu Chen Daobin Feng Cuisong Zhu Jun fan Shuye Zhang Xiaoyan Zhang jianqing Xu Clinical Center for Bio-Therapy Zhongshan HospitalFudan University(Xiamen Branch)Shanghai200032China Center for Infectious Disease Research Science of Life SciencesWestlake UniversityHangzhou310024China Shanghai Public Health Clinical Center&Institutes of Biomedical Sciences Shanghai Medical CollegeFudan UniversityShanghai201508China

Influenza A virus(IAV),responsible for seasonal epidemics and recurring pandemics,represents a global threat to public health.Given the risk of a potential IAV pandemic,it is increasingly important to better understand virushost interactions and develop new anti-viral strategies.Here,we reported nonmuscle myosin IIA(MYH9)-mediated regulation of IAV infection.MYH9 depletion caused a profound inhibition of IAV infection by reducing viral attachment and internalization in human lung epithelial cells.Surprisingly,overexpression of MYH9 also led to a significant reduction in viral productive infection.Interestingly,overexpression of MYH9 retained viral attachment,internalization,or uncoating,but suppressed the viral ribonucleoprotein(vRNP)activity in a minigenome system.Further analyses found that excess MYH9 might interrupt the formation of vRNP by interacting with the viral nucleoprotein(NP)and result in the reduction of the completed vRNP in the nucleus,thereby inhibiting subsequent viral RNA transcription and replication.Together,we discovered that MYH9 can interact with IAV NP protein and engage in the regulation of vRNP complexes,thereby involving viral replication.These findings enlighten new mechanistic insights into the complicated interface of host-IAV interactions,ultimately making it an attractive target for the generation of antiviral drugs.

关键词： Myosin IIA(MYH9) Influenza A virus(IAV) vRNP activity Virus-host interactions Virus entry

Penalized least squares estimation with weakly dependent data

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Science China Mathematics 2016年第12期59卷 2335-2354页

作者： fan jianqing QI Lei TONG Xin Department of Operations Research Princeton University Department of Data Sciences and Operations University of Southern California

在统计和机器学习社区，最后十五年见证惩罚方法和另外的最先进的可变选择技术支持的高度维的模型的巨浪。我们指的高度维的模型不同于传统的模型因为所有参数 p 的数字和重要参数 s 的数字两个都被允许与样品尺寸 T 成长。当地特定的... 详细信息

在统计和机器学习社区，最后十五年见证惩罚方法和另外的最先进的可变选择技术支持的高度维的模型的巨浪。我们指的高度维的模型不同于传统的模型因为所有参数 p 的数字和重要参数 s 的数字两个都被允许与样品尺寸 T 成长。当地特定的知识是初步的并且鉴于从遗传，金融和联机聚会的数据的最近、潜在的富裕，联网时，等等，如此的( s ， T ， p )三重地分叉的模型以当模特儿享受最终的灵活性，并且他们能是被使用一指导数据首先调查走。然而，模型选择一致性和另外的理论性质仅仅为独立数据被探讨，让时间系列大部分揭开了。在赋予以一个弱依赖的序列的一个简单线性回归模型上，这份报纸适用一惩罚最少的广场(请) 途径。在整齐条件下面，我们显示出符号一致性，为评价错误与高概率导出有限样品界限，并且请证明那估计在有率 \ 的 L 2 标准是一致的(\sqrt { s\log s/T }\) 。

关键词：弱依赖高度维的模型神谕性质为选择一致性建模惩罚最少的广场

利用SAS软件中的PROC MCMC过程步实现二分类数据的贝叶斯Meta分析

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中国循证医学杂志 2021年第2期21卷 210-218页

作者：范丽蓉郑建清福建医科大学附属第二医院门诊部福建泉州362000 福建医科大学附属第二医院肿瘤放射治疗科福建泉州362000

目的介绍利用SAS软件中的PROC MCMC过程步实现二分类数据的贝叶斯Meta分析。方法以已发表系统评价数据作为实例,利用SAS软件中的PROC MCMC实现二分类数据的贝叶斯Meta分析,并提供编程代码。结果以比值比(odds ratio,OR)的对数转换值作... 详细信息

目的介绍利用SAS软件中的PROC MCMC过程步实现二分类数据的贝叶斯Meta分析。方法以已发表系统评价数据作为实例,利用SAS软件中的PROC MCMC实现二分类数据的贝叶斯Meta分析,并提供编程代码。结果以比值比(odds ratio,OR)的对数转换值作为效应值,基于正态分布构建的贝叶斯Meta分析结果与频率学方法给出的结果极为相似。结论基于SAS强大的编程能力,PROC MCMC可非常方便地实现二分类数据的贝叶斯Meta分析。随着贝叶斯统计理论的快速发展,贝叶斯Meta分析在Meta分析领域将发挥越来越重要的作用。

关键词：贝叶斯Meta分析二分类数据 PROC MCMC过程步正态分布 SAS软件

A tribute to Professor Xiru Chen Regularity Properties for Sparse Regression

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Communications in Mathematics and Statistics 2016年第1期4卷 1-19页

作者： Edgar Dobriban Jianqing Fan Department of Statistics Stanford UniversityStanfordUSA Department of Operations Research and Financial Engineering Princeton UniversityPrincetonUSA

Statistical and machine learning theory has developed several conditionsensuring that popular estimators such as the Lasso or the Dantzig selector performwell in high-dimensional sparse regression,including the restricted eigenvalue,compatibility,and lq sensitivity properties.However,some of the central aspects of theseconditions are not well understood.For instance,it is unknown if these conditions canbe checked efficiently on any given dataset.This is problematic,because they are atthe core of the theory of sparse regression.Here we provide a rigorous proof that theseconditions are NP-hard to check.This shows that the conditions are computation-ally infeasible to verify,and raises some questions about their practical applications.However,by taking an average-case perspective instead of the worst-case view of NP-hardness,we show that a particular condition,Cq sensitivity,has certain desirableproperties.This condition is weaker and more general than the others.We show thatit holds with high probability in models where the parent population is well behaved,and that it is robust to certain data processing steps.These results are desirable,as theyprovide guidance about when the condition,and more generally the theory of sparseregression,may be relevant in the analysis of high-dimensional correlated observa-tional data.

关键词： High-dimensional statistics Sparse regression Restricted eigenvalue lq sensitivity Computational complexity

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基于倾斜摄影测量和BIM技术的三维建模

科技创新与应用 2020年第29期10卷 54-55页

作者：樊鉴庆宿迁学院江苏徐州211600

根据目前无人机倾斜摄影测量和BIM技术的三维建模研究现状进行分析可知,这一技术在水利工程中已经基本普及,相关人员利用无人机倾斜摄影技术可以直观的得到工程的三维实景模型,利用BIM技术则可以得到清晰的工程设计模型,因此,利用适当... 详细信息

根据目前无人机倾斜摄影测量和BIM技术的三维建模研究现状进行分析可知,这一技术在水利工程中已经基本普及,相关人员利用无人机倾斜摄影技术可以直观的得到工程的三维实景模型,利用BIM技术则可以得到清晰的工程设计模型,因此,利用适当的手段把这两种技术进行融合便可以直观的得到水利工程模型,达到设计与实景完美结合的目的,从而减少施工中的误差,比如测量误差等,能够较好的确保工程中的相关数据的准确性与一致性。

关键词：无人机倾斜摄影 BIM 三维设计

Changes in neuronal apoptosis and apoptosis modulatory factors in cerebral ischemia/reperfusion

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Neural Regeneration Research 2007年第6期2卷 344-349页

作者： Liying Qiu Ying Li Hongbin fan Bin Du Zhiyong Yang jianqing Cheng Division of Basic Medical Science School of Medicine Meiyuan Branch of Southern Yangtze University Wuxi China

BACKGROUND： The high concentration of glutamate release is the main cause for neuronal cell death. The relationship between glutamate level and apoptosis during ischemia/reperfusion injury is still unclear. OBJECTIVE： To observe the neuronal apoptosis at 24 and 72 hours following cerebral ischemia/reperfusion in rats, and analyze the possible influencing factors. DESIGN： A randomized controlled animal experiment. SETTING： School of Medicine, Southern Yangtze University. MATERIALS： Totally 30 male adult Sprague Dawley （SD） rats of clean grade, weighing 240 - 290 g, were obtained from Shanghai Experimental Animal Center, Chinese Academy of Sciences. The rats were randomly divided into sham-operated group （n=10） and model group （n=20）. Each group was observed at 24 and 72 hours after ischemia/reperfusion, 5 rats at each time point in the sham-operated group, whereas 12 at 24 hours and 8 at 72 hours in the model group. Kits for determining apoptosis and Bcl-2 were bought from Wuhan Boster Biological Technology, Co., Ltd.; Kit for calcineurin from Nanjing Jiancheng Bioengineering Institute. METHODS： The experiment was carried out in the Functional Scientific Research Room of Southern Yangtze University from June to October in 2006.①Right middle cerebral artery was occluded by inserting a thread through internal carotid artery （ICA）. The surgical process for the sham-operated rats was the same as that in the model group except a nylon suture inserted the ICA. According to Longa five-degree standard, the neurological deficit evaluation of rats was evaluated after surgery, and grades 1 - 3 were taken as successful model establishment. The blood was recirculated by withdrawing the nylon filament under anesthesia at 2 hours after ischemia in successful rat models. ②After reperfusion, the brain tissue was quickly removed at 24 or 72 hours and the slices were obtained from optic chiasma to funnel manubrium. The changes of the number of apoptotic cells were observed using the terminal deoxynucleotidyl transferase mediated dUT

关键词： brain ischemia reperfusion injuries excitatory amino acids cell apoptosis

证券投资基金规模适度性研究——基于中国市场的证据

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金融研究 2022年第3期 189-206页

作者：张琳琳沈红波范剑青复旦大学社会发展与公共政策学院/经济学院上海200433 普林斯顿大学金融工程系美国新泽西州08544

随着社保、养老金等中长期资金的大规模入市,中国公募基金规模面临更快扩张,那么基金规模究竟是可以无限扩张还是存在制约?本文研究发现,基金规模扩张会受到基金经理与投资者之间的委托代理冲突、边际规模报酬递减、投资者大规模赎回的... 详细信息

随着社保、养老金等中长期资金的大规模入市,中国公募基金规模面临更快扩张,那么基金规模究竟是可以无限扩张还是存在制约?本文研究发现,基金规模扩张会受到基金经理与投资者之间的委托代理冲突、边际规模报酬递减、投资者大规模赎回的制约。基于此,本文提出了基金管理规模适度区间的概念及其相应计量模型,并借此对2011—2019年间中国公募基金市场规模的适度性进行实证判断和检验,结果显示:(1)中国公募基金的平均管理规模在2015年之前过大,2016年之后趋向适度,而在2019年出现偏小现象。(2)中国基金市场规模适度区间的上、下限呈现逐年减小趋势,但二者的差值,即适度性区间的宽度却逐年增加。(3)规模适度基金的业绩表现远好于规模不足和规模过大两类基金,但市场上的规模适度基金占比则小于另外两类基金。最后,本文就如何提升公募基金,尤其是对安全性和盈利性要求更高的养老保险基金的规模适度性提出了相应对策建议。

关键词：基金规模适度性最优规模基金业绩