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Optimization and verification of free flight separation similarity law in high-speed wind tunnel

Chinese Journal of Aeronautics 2020年第2期33卷 501-507页

作者： fei xue Xin JIN Peihua FENG Han QIN Zenghui JIANG Yuchao WANG Peng BAI China Academy of Aerospace Aerodynamics Beijing 100074China AVIC Chengdu Aircraft Design&Research Institute Chengdu 610091China Beijing Machinery and Electronics Engineering Institute Beijing 100074China

Based on the similarity of separation time,a similarity law optimization method for high-speed weapon delivery test is *** typical separation state under wind load is simulated by the numerical *** real separation data of aircraft,separation data of previous test methods,separation data of ideal wind tunnel test of previous methods,and simulation data of the proposed optimization method are obtained.A comparison of the data shows that the method proposed can improve the performance of *** law optimization starts with the development of motion equations and dynamic equations in the windless state to address the problems of mismatching between vertical and horizontal displacement,and to address the problems of separation trajectory distortion caused by insufficient gravity acceleration of the scaling model of existing light *** ejection velocity of the model is taken as a factor/vector,and is adjusted reasonably to compensate the linear displacement insufficiency caused by the insufficient vertical acceleration of the light model method,so as to ensure the matching of the vertical and horizontal displacement of the projectile,and to improve the consistency between the test results of high-speed projection and the actual separation *** optimized similarity law is applicable to many existing free-throwing modes of high-speed wind *** optimized similarity law is not affected by the ejection velocity and hanging mode of the *** optimized similarity law is suitable not only for the launching of the buried ammunition compartment and external stores,but also for the test design of projectile launching and gravity separation.

关键词： Carrier and missile interference Ejection separation Gravity separation High-speed weapon delivery Multi-body separation Similarity law optimization

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CLINICOPATHOLOGICAL SIGNIFICANCE OF PTEN AND CASPASE-3 EXPRESSIONS IN BREAST CANCER

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Chinese Medical Sciences Journal 2008年第2期23卷 95-102页

作者： xue-fei Yang Yan Xin Li-li Mao The Fourth Laboratory of Cancer Institute ＆ Department of Tumor Pathology of General Surgery Institute the First Hospital of China Medical University Shenyang 110001

Objective To investigate the expressions of PTEN and Caspase-3 proteins in human breast carcinoma,and to evaluate their clinicopathological implications during the tumorigenesis and progression of breast *** The expressions of PTEN and Caspase-3 proteins in 95 cases of breast cancer and 15 cases of benign breast diseases were investigated *** between the expression of PTEN protein,Caspase-3 protein,and clinicopathological features of breast cancers were *** The loss expression rate of PTEN protein in tumor tissues was significantly higher than that in benign breast diseases(33.7% vs.0,P0.05).In addition,the expression of PTEN protein had significantly positive correlation with the expression of Caspase-3 protein in breast cancer(P<0.01).Conclusion The combination detection of PTEN and Caspase-3 may serve as an important index to estimate the pathobiological behavior and prognosis of breast cancer.

关键词： breast cancer tumor suppressor gene PTEN Caspase-3 prognosis

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The Relation between the Critical Accretion Rate of Progenitors of SNe Ia and Metallicity

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Chinese Journal of Astronomy and Astrophysics 2006年第4期6卷 461-469页

作者： Xiang-Cun Meng xue-fei Chen Christopher A. Tout Zhan-Wen Han National Astronomical Observatories / Yunnan Observatory Chinese Academy of Sciences Kunming 650011 Graduate School of Chinese Academy of Sciences Beijing 100049 Institute of Astronomy The Observatories Madingley Road Cambridge CB3 0HA England Centre for Stellar and Planetary Astrophysics School of Mathematics Monash University Clayton Victoria 3800 Australia

A carbon-oxygen white dwarf may *** a Type Ia supernova by accreting matter from its companion via either Roche lobe overflow or from winds, but there exists a critical accretion rate of the progenitor system for the explosion. We study the relation between the critical accretion rate and the metallicity via an AGB star approach. The result indicates that the critical accretion rate depends not only on the hydrogen mass fraction and the white dwarf mass, but also on the metallicity. The effect of the metallicity is smaller than that of the white dwarf mass. We show that it is reasonable to use the model with stellar mass 1.6 M⊙ for real white dwarfs.

关键词： stars: evolution -- star: AGB -- star: supernova: general

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Lactate dehydrogenase:An important molecule involved in acetamizuril action against Eimeria tenella

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Journal of Integrative Agriculture 2020年第5期19卷 1332-1339页

作者： LIU Li-li fei Chen-zhong DONG Hui ZHANG Ke-yu Fu Jian-jun LI Tao xue fei-qun Key Laboratory of Animal Parasitology Ministry of Agriculture/Shanghai Veterinary Research InstituteChinese Academy of Agricultural SciencesShanghai 200241P.R.China East China University of Science and Technology Shanghai 200237P.R.China

Lactate dehydrogenase(LDH),a vital enzyme in anaerobic glycolysis,is closely associated with the survival of *** studies of some parasites have shown that LDH exhibits unique physicochemical properties and molecular structures and may be an ideal potential target for diagnosis and drug *** this study,we aimed to investigate the effects of acetamizuril,a novel anticoccidial compound,on LDH in the second-generation merozoites of Eimeria tenella(mz-LDH).Quantitative real-time PCR,Western blot,immunofluorescence and enzyme activity assays were each applied to detect the changes of *** results indicated that the mRNA and protein levels of mz-LDH were reduced upon acetamizuril *** of mz-LDH demonstrated that considerable amount of mz-LDH was distributed around or in the nuclei of second-generation merozoites within the untreated group;in contrast,the acetamizuril-treated group had very low level of ***,LDH enzyme activity assay suggested that a decreased LDH enzyme activity in both cytoplasm and nucleus of merozoites in the acetamizuril-treated ***,the induced apoptosis in second-generation merozoites by the acetamizuril was evaluated by detecting caspase 3 activity,and acetamizuril was found to significantly increase caspase 3 *** above findings show that LDH may play an important role in the mediating the activity of acetamizuril against coccidiosis,and further investigation into this aspect might contribute to new light on the pathogenesis of *** during its interaction with acetamizuril.

关键词： acetamizuril lactate dehydrogenase E.tenella second-generation merozoites

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Transparent paper-based triboelectric nanogenerator as a page mark and anti-theft sensor

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Nano Research 2014年第8期7卷 1215-1223页

作者： Limin Zhang fei xue Weiming Du Changbao Han Chi Zhang Zhonglin Wang Beijing Institute of Nanoenergy and Nanosystems Chinese Academy of Sciences Beijing 100083 China School of Material Science and Engineering Georgia Institute of Technology Atlanta Georgia 30332 USA

The triboelectric nanogenerator （TENG）, based on the well-known triboelectric effect and electrostatic induction effect, has been proven to be a simple, cost effective approach for self-powered systems to convert ambient mechanical energy into electricity. We report a flexible and transparent paper-based triboelectric nanogenerator （PTENG） consisting of an indium tin oxide （ITO） film and a polyethylene terephthalate （PET） film as the triboelectric surfaces, which not only acts as an energy supply but also as a self-powered active sensor. It can harvest kinetic energy when the sheets of paper come into contact, bend or slide relative to one another by a combination of vertical contact-separation mode and lateral sliding mode. In addition, we also integrate grating-structured PTENGs into a book as a self-powered anti-theft sensor. The mechanical agitation during handling the book pages can be effectively converted into an electrical output to either drive a commercial electronic device or trigger a warning buzzer. Furthermore, different grating-structures on each page produce different numbers of output peaks by sliding relative to one another, which can accurately act as a page mark and record the number of pages turned. This work is a significant step forward in self-powered paper-based devices.

关键词： paper-based triboelectric nanogenerator self-powered systems anti-theft sensor position indium tin oxide

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Associations of decimetric type Ⅲ bursts with coronal mass ejections and Hα flares

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Research in Astronomy and Astrophysics 2010年第5期10卷 484-494页

作者： Yuan Ma De-Yu Wang Jun Lin Shuo Dai xue-fei Zhang National Astronomical Observatories of China / Yunnan Astronomical Observatory ChineseAcademy of Sciences Kunming 650011 China Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008 China Harvard-Smithsonian Center for Astrophysics Cambridge MA 02138 USA

We present a statistical study of decimetric type Ⅲ radio bursts, coronal mass ejections （CMEs）, and Hα flares observed in the period from July 2000 to March 2005. In total, we investigated 395 decimetric type Ⅲ radio burst events, 21% of which showed apparent correlation to CMEs that were associated with Hα flares. We noticed that the Hα flares which were strongly associated with CMEs were gradual events, and 82% of them took place before CMEs appeared in the field of view of LASCO C2; that most of the CME-associated radio bursts started in the frequency range around 750 MHz with a frequency drifting rate of several hundred MHz s-1, of which both positive and negative ones were recognized; and that the correlation of type Ⅲ radio bursts to CMEs without associated flares is fairly vague, less than 9%.

关键词： Sun: magnetic fields — Sun: flares — Sun: radio bursts — Sun: coronal mass ejections

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Effects of α-Enhancement on Stellar Evolution

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Chinese Journal of Astronomy and Astrophysics 2008年第3期8卷 262-268页

作者： Jian-Po Guo Feng-Hui Zhang xue-fei Chen Zhan-Wen Han National Astronomical Observatories / Yunnan Observatory Chinese Academy of Sciences Kunming650011 China Graduate School of-Chinese Academy of Sciences Beijing 100049 China

Using Eggleton＇s code, we systematically show the differences in stellar evolution between the results based on the scaled-solar mixture and the a-enhanced metal mixture. As input, the OPAL high temperature opacities are used for log（T/K）〉 4.00, and the new Wichita State low temperature opacities, for log（T/K） ≤ 4.00, Our calculations cover star masses ranging from 0.25 to 80.0M⊙, spaced at ΔlogM = 0.10 or 0.05. The values of metallicities Z are 0.0001, 0.0003, 0.001, 0.004, 0.01, 0.02, 0.03, 0.04, 0.06, 0.08 and 0.10. For a given Z, the initial hydrogen mass fraction is given by X = 0.76 - 3.0Z. We show that a-enhancement can raise the stellar effective temperature and luminosity, and reduce the evolutionary age. Compared with some previous work, the effects of α-enhancement are more obviously demonstrated in our calculations.

关键词： abundances -- stars evolution -- stars general

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The cotton WRKY transcription factor GhWRKY70 negatively regulates the defense response against Verticillium dahliae

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The Crop Journal 2019年第3期7卷 393-402页

作者： Xianpeng Xiong Shichao Sun Yanjun Li Xinyu Zhang Jie Sun fei xue Key Laboratory of Oasis Eco-agriculture College of Agriculture Shihezi University

WRKY transcription factors (TFs) play important roles in the regulation of biotic and abiotic stresses. However, the functions of most WRKY TFs in upland cotton (Gossypium hirsutum) are still unknown. In this study, we functionally identified a group Ⅲ WRKY transcription factor, GhWRKY70, in upland cotton. Reverse transcription-quantitative PCR analysis showed that GhWRKY70 expression was induced by Verticillium dahliae, salicylic acid (SA) and methyl jasmonate. Virus-induced gene silencing of GhWRKY70 increased the resistance of cotton to V. dahliae. Specifically, jasmonic acid (JA) response-associated genes were upregulated and SA-related genes were downregulated in GhWRKY70-silenced cotton plants. Overexpression of GhWRKY70 reduced tolerance to V. dahliae in Arabidopsis thaliana. Transgenic Arabidopsis plants showed increased expression of SA-associated genes and reduced expression of JA response-associated genes. These results suggest that GhWRKY70 negatively regulates tolerance to V. dahliae in at least two ways: (ⅰ) by upregulating the expression of SA-associated genes and (ⅱ) by reducing the expression of JA-associated genes.

关键词： WRKY transcription factors Gossypium hirsutum Verticillium dahliae SA JA

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Color excesses of type Ia supernovae from the single-degenerate channel model

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Research in Astronomy and Astrophysics 2009年第11期9卷 1259-1269页

作者： Xiang-Cun Meng xue-fei Chen Zhan-Wen Han Wu-Ming Yang School of Physics and Chemistry Henan Polytechnic University Jiaozuo 454000 China National Astronomical Observatories/Yunnan Observatory Chinese Academy of Sciences Kunming650011 China

The single degenerate model is the most widely accepted progenitor model of type Ia supernovae （SNe Ia）, in which a carbon-oxygen white dwarf （CO WD） accretes hydrogen-rich material from a main sequence or a slightly evolved star （WD＋MS） to increase its mass, and explodes when its mass approaches the Chandrasekhar mass limit. During the mass transfer phase between the two components, an optically thick wind may occur and the material lost as wind may exist as circumstellar material （CSM）. Searching for the CSM around a progenitor star is helpful for discriminating different progenitor models of SNe Ia. In addition, the CSM is a source of color excess. The purpose of this paper is to study the color excess produced from the single-degenerate progenitor model with an optically thick wind, and reproduce the distribution of color excesses of SNe Ia. Meng et al. systemically carded out binary evolution calculations of the WD ＋MS systems for various metallicities and showed the parameters of the systems before Roche lobe overflow and at the moment of supernova explosion in Meng ＆ Yang. With the results of Meng et al., we calculate the color excesses of SNe Ia at maximum light via a simple analytic method. We reproduce the distribution of color excesses of SNe Ia by our binary population synthesis approach if the velocity of the optically thick wind is taken to be an order of magnitude of 10km s^-1. However, if the wind velocity is larger than 100km s^-1, the reproduction is bad.

关键词： stars white dwarfs -- stars supernova general

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Three-dimensional domain swapping as a mechanism to lock the active conformation in a super-active octamer of SARS-CoV main protease

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Protein & Cell 2010年第4期1卷 371-383页

作者： Shengnan Zhang Nan Zhong fei xue xue Kang Xiaobai Ren Jiaxuan Chen Changwen Jin Zhiyong Lou Bin Xia Beijing Nuclear Magnetic Resonance Center Peking UniversityBeijing 100871China College of Chemistry and Molecular Engineering Peking UniversityBeijing 100871China Structural Biology Laboratory Tsinghua UniversityBeijing 100084China College of Life Sciences Peking UniversityBeijing 100871China

Proteolytic processing of viral polyproteins is indispensible for the lifecycle of *** main protease(M^(pro))of SARS-CoV is an attractive target for anti-SARS drug development as it is essential for the polyprotein processing.M^(pro) is initially produced as part of viral polyproteins and it is matured by ***,we report that,with the addition of an N-terminal extension peptide,M^(pro) can form a domain-swapped *** complete removal of the extension peptide from the dimer,the mature M^(pro) self-assembles into a novel super-active octamer(AO-M^(pro)).The crystal structure of AO-M^(pro) adopts a novel fold with four domainswapped dimers packing into four active units with nearly identical conformation to that of the previously reported M^(pro) active dimer,and 3D domain swapping serves as a mechanism to lock the active conformation due to entanglement of polypeptide *** with the previously well characterized form of M^(pro),in equilibrium between inactive monomer and active dimer,the stable AO-M^(pro) exhibits much higher proteolytic activity at low *** all eight active sites are bound with inhibitors,the polyvalent nature of the interaction between AO-M^(pro) and its polyprotein substrates with multiple cleavage sites,would make AO-M^(pro) functionally much more superior than the M^(pro) active dimer for polyprotein ***,during the initial period of SARS-CoV infection,this novel active form AOM^(pro) should play a major role in cleaving polyproteins as the protein level is extremely *** discovery of AOM^(pro) provides new insights about the functional mechanism of M^(pro) and its maturation process.

关键词： SARS-CoV main protease crystal structure 3D domain swapping polyprotein processing

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