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Generalized Latin Matrix and Construction of Orthogonal Arrays

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Acta Mathematicae Applicatae Sinica 2017年第4期33卷 1083-1092页

作者： Shan-qi PANG li-yan chen College of Mathematics and Information Science Henan Engineering Laboratory for Big Data Statistical Analysis and Optimal Control Henan Normal University Xinxiang 453007 China Anyang Preschool Education College Anyang 456150 China

In this paper, generalized Latin matrix and orthogonal generalized Latin matrices are proposed. By using the property of orthogonal array, some methods for checking orthogonal generalized Latin matrices are presented. We study the relation between orthogonal array and orthogonal generalized Latin matrices and obtain some useful theorems for their construction. An example is given to illustrate applications of main theorems and a new class of mixed orthogonal arrays are obtained.

关键词： orthogonal array generalized Latin matrix orthogonal generalized Latin matrices matrix image generalized permutation difference matrix

Aeroelastic modeling of wind loading on a cable-net supported glass wall

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Acta Mechanica Sinica 2010年第3期26卷 409-415页

作者： Zhifu Gu Letian yang yan li Bin chen LTCS and College of Engineering Peking University 100871 Beijing China

Wind loading study on a cable-net supported glass wall is conducted by means of wind tunnel tests. An equiva- lent aeroelastic model is designed and constructed. Response of displacements of the wall is measured and analyzed. In order to design a glass wall under wind loading, the ＂wind- vibration factor＂ is estimated and discussed. In fact, the mech- anism of wind acting on the wall is commonly known not only as positive pressure, but also as negative pressure caused by the flow separation on the corners of the building. Due to the diffidence in the mechanism of wind acting, two typi- cal response cases are classified. The results show that the dynamic response of the structure caused by the negative pressure is stronger than that of the positive pressure case. To determine the aerodynamic wind loading on a flexible part of structure on a building, wind tunnel study may be useful and play an important role.

关键词： Wind tunnel study Cable-net supported glasswall - Wind-vibration factor Aeroelastic model

Theoretical Studies on the Iodine-catalyzed Nucleophilic Addition of Acetone with Five-membered Heterocycles

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Chemical Research in Chinese Universities 2008年第4期24卷 520-524页

作者： WANG yan-hua li li chen Xue-song College of Biology and Environment Engineering Zhejiang Shuren University Hangzhou 310015 P. R. China

The iodine-catalyzed nucleophilic addition reactions of pyrrole, furan, or thiophene with acetone were studied in gas and solvent by the density functional theory at the level of Lanl2DZ^＊. It was seen that the halogen bond between iodine and carbonyl oxygen appeared to have an important catalytic effect on such reactions, and the first iodine molecule maximally diminished the barrier height by 41 kJ/mol, while the second iodine molecule could not improve such reactions largely. It was concluded that the C2-addition was generally more favorable than the C3-addition for the three heterocycles; however, iodine considerably more effectively catalyzed the C3-addition than the C2-addition for pyrrole. It was also revealed by PCM calculation that the iodine-catalyzed nucleophilic additions occurred more easily in solvent than in gas, which explained the experiment performed by Bandgar et al..

关键词： Halogen bond, Catalytic effect Nucleophilic addition Density functional theory

Synthesis and antitumor activity of heterocyclic acid ester derivatives of 20S-camptothecins

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Chinese Chemical Letters 2007年第11期18卷 1335-1338页

作者： Di Zao li yan li Xiao Guang chen chen Gen Zhu Jing yang Hong yan liu Xian Dao Pan Institute of Materia Medica Chinese Academy of Medical Sciences ＆ Peking Union Medical College Beijing 100050 China

A series of heterocyclic acid esters of camptothecins as new compounds had been synthesized by acylation method, their in vitro and in vivo antitumor activities were evaluated. The cytotoxic results showed that 6 possessed the best efficacy on six human cancer cell lines in the six classes of CPTs＇ derivatives. In vivo testing results indicated that 9 had better antitumor activity against mouse liver carcinoma H22 than topotecan.

关键词： Camptothecin Synthesis Heterocyclic acid Antitumor activity

H_∞ controller design for a 4-meter direct-drive azimuth axis

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Research in Astronomy and Astrophysics 2015年第11期15卷 1931-1944页

作者： li-yan chen Zhen-Chao Zhang Xiao-li Song Da-Xing Wang National Astronomical Observatories Nanjing Institute of Astronomical Optics & TechnologyChinese Academy of Sciences Key Laboratory of Astronomical Optics & Technology Nanjing Institute of Astronomical Optics & Technology Chinese Academy of Sciences University of Chinese Academy of Sciences

To pursue a higher imaging resolution for exploring more details in the information conveyed by the Universe, the next generation of optical telescopes based on a direct drive widely employ the extremely large aperture structure, which also introduces more disturbances and uncertain factors to the control system. Facing this new challenge, the PID control method in main-axis control systems of traditional astronomical telescopes cannot suffice for the requirement of the tracking precision and disturbance sensitivity in angular velocity. To overcome this shortcoming, we establish a dynamic model and propose an H∞ controller for a 4-meter azimuth direct drive control system that consists of a revolving platform（azimuth axis）, a three-phase torque motor, a motor drive, an encoder, a data acquisition card and a small computers. Simulations are carried out to analyze the model and guide the real *** results show that the proposed H∞ controller reduces the tracking error by a maximum of 80.69%（average 57.8%） and the disturbance sensitivity by a maximum of 82.3%（average 50.96%） compared with the traditional tuned PI controller;furthermore, the order of the model describing the proposed controller can be reduced to three, thus its feasibility in real systems is guaranteed.

关键词： disturbance azimuth uncertain guaranteed torque details encoder aperture conveyed pursue

Coarsening and Age Hardening Behaviors of γ' Particles in GH742 During High Temperature Treatment

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Journal of Iron and Steel Research International 2009年第5期16卷 81-86页

作者： li Hong-yu SONG Xi-ping WANG yan-li chen Guo-liang State Key Lab for Advanced Metals and Materials University of Science and Technology Beijing Beijing 100083 China

The coarsening and ageing hardening behaviors of γ′ particles in superalloy GH742 have been investigated by field emission scanning electron microscopy （FESEM）, coarsening kinetics calculation and microhardness testing when ageing at 1 050, 950 and 900 ℃ for different time. The cube of γ′ particle size and ageing time follows a linear law as predicted by LSW theory. The particle size distributions give better fit to the LSW theoretical distribution. The activation energy for γ′ coarsening is accurately determined to have 245. 06±14.42 kJ/mol when considering the effect of temperature on the solution concentrations in matrix. Based on the activation energy, the coarsening kinetics of γ′ particle is predicted as r^-t^3=7.35×10^15 Ce/T exp -（245060±14420）/RT *** microhardness studies indicate that microhardness decreases rapidly with increasing the ageing temperature and it has a maximum value corresponding to a critical particle size beyond which the microhardness increase stalls with increasing the ageing time.

关键词： superalloy γ′ particle coarsening kinetics activation energy microhardness

Role of cathepsin B-mediated apoptosis in fulminant hepatic failure in mice

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World Journal of Gastroenterology 2009年第10期15卷 1231-1236页

作者： Bing-Zhu yan Wei Wang li-yan chen Man-Ru Bi yan-Jie Lu Bao-Xin li Bao-Shan yang Department of Infectious Diseases the SecondClinical Hospital of Harbin Medical University Harbin 150086China Department of Pharmacology HarbinMedical University Harbin 150086 China

AIM: To investigate the pathogenic role of cathepsin B and the protective effect of a cathepsin B inhibitor (CA074Me) in fulminant hepatic failure in mice. METHODS: LPS/D-Gal N was injected into mice of the model group to induce fulminant hepatic failure; the protected group was administered CA-074me for 30 min before LPS/D-Gal N treatment; the normal group was given isochoric physiologic saline. liver tissue histopathology was determined with HE at 2, 4, 6 and 8 h after Lps/D-Gal injection. Hepatocyte apoptosis was examined by TUNEL method. The expression of cathepsin B in liver tissues was investigated by immunohistochemistry, Western blot and RT-PCR. RESULTS: Compared with the normal group, massive typical hepatocyte apoptosis occurred in the model group; the number of apoptotic cells reached a maximum 6 h after injection. The apoptosis index (AI) in the protected group was clearly reduced (30.4 ± 2.8 vs 18.1 ± 2.0, P liver injury.

关键词： Fulminant hepatic failure Hepatocyteapoptosis Cathepsin B CA-O74me

Role of neutrophil chemoattractant CXCL5 in SARS-CoV-2 infection-induced lung inflammatory innate immune response in an in vivo hACE2 transfection mouse model

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Zoological Research 2020年第6期41卷 621-631页

作者： yan liang Heng li Jing li Ze-Ning yang Jia-li li Hui-Wen Zheng yan-li chen Hai-Jing Shi Lei Guo Long-Ding liu Institute of Medical Biology Chinese Academy of Medical SciencesKunmingYunnan 650118China

Understanding the pathogenesis of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)and clarifying antiviral immunity in hosts are critical aspects for the development of vaccines and *** are frequently used to generate animal models of infectious diseases due to their convenience and ability to undergo genetic ***,normal adult mice are not susceptible to ***,we developed a viral receptor(human angiotensin-converting enzyme 2,hACE2)pulmonary transfection mouse model to establish SARS-CoV-2 infection rapidly in the mouse *** on the model,the virus successfully infected the mouse lung 2 days after *** RNA/protein,innate immune cell infiltration,inflammatory cytokine expression,and pathological changes in the infected lungs were observed after *** studies indicated that neutrophils were the first and most abundant leukocytes to infiltrate the infected lungs after viral *** addition,using infected CXCL5-knockout mice,chemokine CXCL5 was responsible for neutrophil ***5 knockout decreased lung inflammation without diminishing viral clearance,suggesting a potential target for controlling pneumonia.

关键词： SARS-CoV-2 Mouse model Lung infection ACE2 Neutrophil CXCL5

Inhibition of tumor angiogenesis by TTF1 from extract of herbal medicine

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World Journal of Gastroenterology 2011年第44期17卷 4875-4882页

作者： Chao liu Xiao-Wan li li-Min Cui liang-Chang li li-yan chen Xue-Wu Zhang Basic Medical College Yanbian University Yanji133002 Jilin Province China Clinical Medical College Yanbian University Yanji 133002 Jilin Province China

AIM:To study the inhibition of tumor angiogenesis by 5,2,4'-trihydroxy-6,7,5'-trimethoxyflavone(TTF1) isolated from an extract of herbal medicine Sorbaria ***:Angiogenic activity was assayed using the chick embryo chorioallantoic membrane(CAM) *** density(MVD) was determined by staining tissue sections immunohistochemically for CD34 using the Weidner capillary counting *** mRNA and protein levels of vascular endothelial growth factor(VEGF),vascular endothelialgrowth factor receptor 2(VEGFR2,Flk-1/KDR),basic fibroblast growth factor(bFGF),cyclo-oxygenase(COX)-2 and hypoxia-inducible factor(HIF)-1α were detected by quantitative real-time polymerase chain reaction and Western blotting ***:The TTF1 inhibition rates for CAM were 30.8%,38.2% and 47.5% with treatment concentrations of 25,50 and 100 μg/embryo × 5 d,*** inhibitory rates for tumor size were 43.8%,49.4% and 59.6% at TTF1 treatment concentrations of 5,10,and 20 μmol/kg,*** average MVD was 14.2,11.2 and 8.5 at treatment concentrations of 5 μmol/kg,10 μmol/kg and 20 μmol/kg TTF1,*** mRNA and protein levels of VEGF,KDR,bFGF,COX-2 and HIF-1α in mice treated with TTF1 were significantly ***:TTF1 can inhibit tumor angiogenesis,and the mechanism may be associated with the down-regulation of VEGF,KDR,bFGF,HIF-1α and COX-2.

关键词： Chinese herbal medicine Sorbaria sorbifolia TTF1 Inhibition Tumor angiogenesis