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Bayesian Regularized Regression Based on Composite Quantile Method

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Acta Mathematicae Applicatae Sinica 2016年第2期32卷 495-512页

作者： Wei-hua ZHAO Ri-quan ZHANG Ya-zhao LU Ji-cai LIU School of Statistics East China Normal UniversityShanghai 200241China School of Science NanTong UniversityNanTong 226007China Department of Mathematics Shanxi Datong UniversityDatong 037009China

Recently, variable selection based on penalized regression methods has received a great deal of attention, mostly through frequentist＇s models. This paper investigates regularization regression from Bayesian perspective. Our new method extends the Bayesian Lasso regression （Park and Casella, 2008） through replacing the least square loss and Lasso penalty by composite quantile loss function and adaptive Lasso penalty, which allows different penalization parameters for different regression coefficients. Based on the Bayesian hierarchical model framework, an efficient Gibbs sampler is derived to simulate the parameters from posterior distributions. Furthermore, we study the Bayesian composite quantile regression with adaptive group Lasso penalty. The distinguishing characteristic of the newly proposed method is completely data adaptive without requiring prior knowledge of the error distribution. Extensive simulations and two real data examples are used to examine the good performance of the proposed method. All results confirm that our novel method has both robustness and high efficiency and often outperforms other approaches.

关键词： composite quantile regression variable selection Lasso adaptive Lasso, Gibbs sampler

SHEsis PCA: A GPU-Based Software to Correct for Population Stratification that Efficiently Accelerates the Process for Handling Genome-Wide Datasets

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Journal of Genetics and Genomics 2015年第8期42卷 445-453页

作者： Jiawei Shen Zhiqiang Li Yongyong Shi Bio-X Institutes Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders (Ministry of Education) Shanghai Jiao Tong University Institute of Social Cognitive and Behavioral Sciences Shanghai Jiao Tong University School of Bio-medical Engineering Shanghai Jiao Tong University shanghai Changning Mental Health Center

Population stratification is a problem in genetic association studies because it is likely to highlight loci that underlie the population structure rather than disease-related loci. At present, principal component analysis （PCA） has been proven to be an effective way to correct for population stratification. However, the conventional PCA algorithm is time-consuming when dealing with large datasets. We developed a Graphic processing unit （GPU）-based PCA software named SHEsisPCA （http：//***/***） that is highly parallel with a highest speedup greater than 100 compared with its CPU version. A cluster algorithm based on X-means was also implemented as a way to detect population subgroups and to obtain matched cases and controls in order to reduce the genomic inflation and increase the power. A study of both simulated and real datasets showed that SHEsisPCA ran at an extremely high speed while the accuracy was hardly reduced. Therefore, SHEsisPCA can help correct for population stratification much more efficiently than the conventional CPU-based algorithms.

关键词： Population stratification Principal component analysis Graphic processing unit Cluster Matched cases and controls Genetic studies

H. pylori Escape Host Immunoreaction Through Inhibiting ILK Expression by VacA

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Cellular & Molecular Immunology 2009年第3期6卷 191-197页

作者： Jianping Yuan Ping Li Jing Tao Xiaodong Shi Baoyu Hu Huabiao Chen Xiaokui Guo Department of Medical Microbiology and Parasitology Shanghai Jiaotong University School of Medicine Shanghai 200025 China Present address： Infectious Disease Division Massachusetts General Hospital Harvard Medical School MA 02114 USA Partners AIDS Research Center and Infectious Disease Division Massachusetts General Hospital Harvard Medical School MA 02129 USA

Helicobacter pylori （H. pylori） persistently colonizes the gastric mucosa despite a vigorous immune response. Vacuolating cytotoxin secreted by H. pylori has turned out to be a potent immunomodulatory toxin, but the signal transduction pathways involved has not been studied in macrophages. We observed in this study that vacA-deficient H. pylori induced significantly higher expression of integrin-linked kinase （ILK） and endothelial nitric oxygen synthase （eNOS）, and significantly more production of reactive oxygen species （ROS） in monocyte/macrophage-like U937 cells, as compared with isogenic vacA^＋ H. pylori. The expression of eNOS mRNA in U937 cells overexpressing ILK was markedly increased compared with those transfected with empty vectors. Thus, vacA-deficient H. pylori appears to upregulate ILK expression, which modulates the expression of eNOS and as a result, stimulates the production of ROS. It is VacA that prevents such a process by inhibiting ILK expression, helping H. pylori escape host immunoreaction. This mechanism explains, at least in part, persistent infection of H. pylori in the stomach.

关键词： H. pylori host immunoreaction ILK

Visible-light-mediated photocatalysis as a new tool for catalytic asymmetric dearomatization(CADA)reactions

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Science Bulletin 2018年第13期63卷 809-811页

作者： Yuan-Zheng Cheng Xiao Zhang Shu-Li You State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China Collaborative Innovation Center of Chemical Science and Engineering.Tianjin 300072 China

Aromatic compounds often serve as widely available and fundamental synthetic materials in polymers,paints,cosmetics,and *** development of novel transformations based on simple aromatics to access highly value-added structures is in great *** this regard,catalytic asymmetric dearomatization(CADA)reactions can convert planar aromatic compounds

关键词：反应能光催化不对称工具合成材料激活过程混合物聚合物

Structure controlling and process scale-up in the fabrication of nanomaterials

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Frontiers of Chemical Science and Engineering 2010年第1期4卷 18-25页

作者： Chunzhong LI Key Laboratory for Ultrafine Materials of Ministry of Education School of Materials Science and EngineeringEast China University of Science&TechnologyShanghai 200237China

Nanotechnology is already having a significant commercial impact,and will very certainly have a much greater impact in the *** research on process engineering and scale-up will be very important for the commercial production and application of nanomaterials,because the properties and structure of nanomaterials are not only determined by the nucleation and growth process,but also strongly affected by the engineering properties,such as the mixing,the heat and mass transfer,and also the distribution of temperature,concentration,*** paper will present some research work in our laboratory on the fabrication of *** on the chemical engineering principle and methods,many kinds of novel nanomaterials can be synthesized and their structure can be easily controlled through adjusting the parameters of the fluid mixing,and the distribution of temperature,residence time and concentration,*** using the micro-mixing,heat and mass transfer and reaction control methods,the host-guest nanocomposites have been assembled and assumed as the novel electroanalytical sensing nanobiocomposite *** on the principles of chemical engineering,the manufacturing technologies for magnetic powders,calcium carbonate,and titanium dioxide have been developed for commercial-scale production,and the largest production scale has reached 15 kt/year.

关键词： nanomaterials assembly structure controlling scale-up engineering properties

Risk-minimizing Hedging Strategy for an Equity-indexed Annuity under a Regime Switching Model

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Acta Mathematicae Applicatae Sinica 2015年第1期31卷 101-110页

作者： Lin-yi QIAN Wei WANG Rong-ming WANG School of Finance and Statistics East China Normal University Department of Mathematic The University of Ningbo

The equity-indexed annuity （EIA） contract offers a proportional participation in the performance of a specified equity index, in addition to a guaranteed return on the single premium. How to manage the risk of the EIA is an important issue. This paper considers the hedging of the EIA. We assume that the parameters of the financial model depend on a continuous-time finite-state Markov chain and the Markov chain is observed, that is the Markov regime switching model. The state of the Markov chain can be interpreted as the state of an economy. Under the regime switching model~ we obtain the risk-minimizing hedging strategy for the EIA.

关键词： equity-indexed annuity regime switching, risk-minimization

Simulation and feature analysis for gas emboli Doppler ultrasound signals

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Chinese Journal of Acoustics 2013年第1期32卷 79-89页

作者： WANG Teng WANG Yuanyuan Department of Electronic Engineering Fudan University

The purpose of this study is to establish the simulation model of the gas emboli by analyzing reasons for features of gas emboli Doppler ultrasound signals. It is useful for the further classification of the solid emboli and gas emboli. First, the model of the radiation force and the drag force is used to calculate forces acting on the gas emboli. Second, the acceleration of the gas emboli is calculated in both the radial direction and the axial direction of the vessel, which is used to calculate the trajectory of the gas emboli in the vessel. Finally, the computer simulation model is established for the gas emboli. Doppler ultrasound signals of the gas emboli and the solid emboli are generated in the simulation experiment. Experimental results show that compared with the solid emboli, the gas emboli acted by the radiation force and the drag force will result in the frequency-domain broaden in the Doppler spectrogram. When the gas emboli circulate from the low speed area to the high speed one and then from the high speed area back to the low speed one, a ＂V＂ shape will be shown in the spectrogram of gas emboli signals. When the gas emboli circulate from the low speed area to the high speed one or from the high speed area to the low speed one, a diagonal shape will be shown for gas emboli signals. It is also shown that features of simulated gas emboli signals match with those of gas emboli signals sampled from clinic. All demonstrate that the simulation method of the gas emboli is reasonable.

关键词： Simulation and feature analysis for gas emboli Doppler ultrasound signals high

Amorphous ferric oxide as a hole-extraction and transfer layer on nanoporous bismuth vanadate photoanode for water oxidation

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Chinese Journal of Catalysis 2017年第6期38卷 1045-1051页

作者： Ling Qian Pengfei Liu Le Zhang Chongwu Wang Shuang Yang Lirong Zheng Aiping Chen Huagui Yang Key Laboratory for Ultrafine Materials of Ministry of Education School of Materials Science and Engineering East China University of Science and Technology Shanghai 200237 China Beijing Synchrotron Radiation Facility Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China

An amorphous ferric oxide layer was prepared on a bismuth vanadate *** resulted in improved charge carrier separation and surface catalytic performance compared with the photoanode without the oxide *** photocurrent of the oxide‐layer‐containing photoanode was2.52mA/cm2at1.23V versus the reversible hydrogen electrode,in potassium phosphate buffer,(0.5mol/L,pH=7.0).The amorphous ferric oxide layer on the photoanode contained low‐valence‐state iron species(FeII),which enabled efficient hole extraction and transfer.

关键词： Ferric oxide layer Amorphous Bismuth vanadate Photoanode Oxygen evolution

Production of transgenic mice by random recombination of targeted genes in female germline stem cells

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分子细胞生物学报:英文版 2011年第2期3卷 132-141页

作者： Yong Zhang Zhaojuan Yang Yunze Yang Shuzeng Wang Lingjun Shi Wenhai Xie Kejing Sun Kang Zou Lei Wang Ji Xiong Jie Xiang Ji Wu School of Life Sciences and Biotechnology Shanghai Jiao Tong UniversityNo.800 Dongchuan RoadMinhang DistrictShanghai 200240China

Oocyte production in most mammalian species is believed to cease before ***,this idea has been challenged with the finding that postnatal mouse ovaries possess mitotically active germ cells.A recent study showed that female germline stem cells(FGSCs)from adult mice were isolated,cultured long term and produced oocytes and progeny after transplantation into infertile ***,we demonstrate the successful generation of transgenic or gene knock-down mice using *** FGSCs from ovaries of 5-day-old and adult mice were isolated and either infected with recombinant viruses carrying green fluorescent protein,Oocyte-G1 or the mouse dynein axonemal intermediate chain 2 gene,or transfected with the Oocyte-G1 specific shRNA expression vector(pRS shOocyte-G1 vector),and then transplanted into infertile *** cells in the ovaries underwent oogenesis and produced heterozygous offspring after mating with wild-type male *** offspring were genetically characterized and the biological functions of the transferred or knock-down genes were *** of genetransfer or gene knock-down was 29%–37%and it took 2 months to produce transgenic *** manipulation of FGSCs is a rapid and efficient method of animal transgenesis and may serve as a powerful tool for biomedical science and biotechnology.

关键词： female germline stem cells gene-transfer knock-down Oocyte-G1 mouse dynein axonemal intermediate chain 2(Dnaic2)