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Effects of Increased Night Temperature on Cellulose Synthesis and the Activity of Sucrose Metabolism Enzymes in Cotton Fiber

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Journal of Integrative Agriculture 2013年第6期12卷 979-988页

作者： TIAN Jing-shan hu Yuan-yuan GAN Xiu-xia ZHANG Ya-li hu xiao-bing GOU Ling LUO Hong-hai ZHANG Wang-feng Key Laboratory of Oasis Eco-Agriculture Xinjiang Production and Construction Group/College of Agronomy Shihezi University

Temperature is one of the key factors that influence cotton fiber synthesis at the late growth stage of cotton. In this paper, using two early-maturing cotton varieties as experimental materials, night temperature increase was stimulated in the field using far-infrared quartz tubes set in semi-mobile incubators and compared with the normal night temperatures （control） in order to investigate the effects of night temperature on the cotton fiber cellulose synthesis during secondary wall thickening. The results showed that the activity of sucrose synthase （SuSy） and sucrose phosphate synthase （SPS） quickly increased and remained constant during the development of cotton fiber, while the activity of acid invertase （AI） and alkaline invertase （NI） decreased, increased night temperatures prompted the rapid transformation of sugar, and all the available sucrose fully converted into cellulose. With night temperature increasing treatment, an increase in SuSy activity and concentration of sucrose indicate more sucrose converted into UDPG （uridin diphosphate-glucose） during the early and late stages of cotton fiber development. Furthermore, SPS activity and the increased concentration of fructose accelerated fructose degradation and reduced the inhibition of fructose to SuSy; maintaining higher value of allocation proportion of invertase and sucrose during the early development stages of cotton fiber, which was propitious to supply a greater carbon source and energy for cellulose synthesis. Therefore, the minimum temperature in the nightime was a major factor correlated with the activity of sucrose metabolism enzymes in cotton fiber. Consequently, soluble sugar transformation and cellulose accumulation were closely associated with the minimum night temperature.

关键词： cotton fiber night temperature sucrose metabolism enzyme activity

A GAN based method for multiple prohibited items synthesis of X-ray security image

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Optoelectronics Letters 2021年第2期17卷 112-117页

作者： LI Da-shuang hu xiao-bing ZHANG Hai-gang YANG Jin-feng Tianjin Key Laboratory for Advanced Signal Processing Civil Aviation University of ChinaTianjin 300300China Institute of Applied Artificial Intelligence of the Guangdong-Hong Kong-Macao Greater Bay Area Shenzhen PolytechnicShenzhen 518055China

Detecting prohibited item based on convolutional neural networks(CNNs) is of great significance to ensure public safety. However, the natural occurrence of such prohibited items is a small-probability event, collecting enough datasets to support CNN training is a big challenge. In this paper, we propose a new method for synthesizing X-ray security image with multiple prohibited items from semantic label images basing on Generative Adversarial Networks(GANs). Theoretically, we can use it to synthesize as many X-ray images as needed. A new generator architecture with Res 2 Net is presented, which is more effective in learning multi-scale features of different prohibited items images. This method is extended by establishing the semantic label library which contains 14 000 images. So we totally synthesize 14 000 Xray security images. The experimental results show the super performance(Fréchet Inception Distance(FID) score of 30.55). And we achieve 0.825 of mean average precision(m AP) with Single Shot Multi Box Detector(SSD) for object detection, demonstrating the effectiveness of our approach.

关键词： image method synthesis

Correlation between Brightness Variability and Spectral Index Variability for Fermi Blazars

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Research in Astronomy and Astrophysics 2022年第8期22卷 23-33页

作者： Wen-Xin Yang hu-bing xiao Hong-Guang Wang Jiang-He Yang Zhi-Yuan Pei De-Xiang Wu Yu-Hai Yuan Jun-hui Fan Center for Astrophysics Guangzhou UniversityGuangzhou 510006China Astronomy Science and Technology Research Laboratory of Department of Education of Guangdong Province Guangzhou 510006China Key Laboratory for Astronomical Observation and Technology of Guangzhou Guangzhou 510006China Shanghai Key Lab for Astrophysics Shanghai Normal UniversityShanghai 200234China Department of Physics and Electronics Science Hunan University of Arts and ScienceChangde 415000China

In this work,theγ-ray photon flux,photon spectral index(α_(ph)),variability index(log V.I.),and the synchrotron peak frequency(log v_(p))are compiled for 851 common blazars from the 3 FGL and 4 FGL catalogs and Fan et *** investigate variability properties for Fermi *** calculations and analyses reach following results:(1)the averaged luminosity,spectral index,and variability index of FSRQs are higher than those of BL Lacs for the whole sample.(2)It is found that the spectral index variation is closely anti-correlated with the luminosity variation implying that the spectrum becomes harder when the source becomes brighter in theγ-ray band.(3)Positive correlations are found between the photon spectral index and bothγ-ray luminosity and variability index(log V.I.)for the whole sample,but anti-correlations are found in the two correlations for *** BL Lac subclass,there is a marginal anti-correlation between the photon spectral index and bothγ-ray luminosity,and a positive correlation between the photon spectral index and the variability index(log V.I.).We think those two positive correlations found for the whole sample are apparent.(4)We adopted the SVM machine learning method to separate BL Lacs and FSRQs in theα_(ph)versus log L_(γ)andα_(ph)versus log *** and proposed that a BCU is an FSRQ candidate if it satisfies log V.I.>-10.119 a+24.855,orα_(ph)>-0.048 log L_(γ)+4.498,otherwise,it is a BL Lac *** classification results are quite consistent with those by Kang et al(2019).

关键词： (galaxies:)BL Lacertae objects:general (galaxies:)quasars:general galaxies:active

The relationship between the radio core-dominance parameter and spectral index in different classes of extragalactic radio sources(Ⅲ)

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Research in Astronomy and Astrophysics 2020年第2期20卷 101-111页

作者： Zhi-Yuan Pei Jun-hui Fan Denis Bastieri Jiang-He Yang hu-bing xiao Wen-Xin Yang Center for Astrophysics Guangzhou UniversityGuangzhou 510006China Astronomy Science and Technology Research Laboratory of Department of Education of Guangdong Province Guangzhou 510006China Dipartimento di Fisica e Astronomia“G.Galilei” Universita di Padova1-35131 PadovaItaly Istituto Nazionale di Fisica Nucleare Sezione di Padova1-35131 PadovaItaly Department of Physics and Electronics Science Hunan University of Arts and ScienceChangde 415000China

Active galactic nuclei(AGNs) can be divided into two major classes,namely radio-loud and radio-quiet AGNs.A small subset of the radio-loud AGNs is called blazars,which are believed to be unified with Fanaroff-Riley type Ⅰ and type Ⅱ(FRI&Ⅱ) radio *** our previous work,we present a latest sample of 966 sources with measured radio flux densities of the core and extended *** sample includes 83 BL Lacs,473 flat spectrum radio quasars,101 Seyferts,245 galaxies,52 FRIs&Ⅱs and12 unidentified *** then calculate the radio core-dominance parameters and spectral indices and study their *** analysis shows that the core-dominance parameters and spectral indices are quite different for different types of *** also confirm that the correlation between core-dominance parameter and radio spectral index extends over all the sources in a large sample presented.

关键词： galaxies:active galaxies:general galaxies:jets quasars:general

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一种改进的民用航空网络空间脆弱性模型

交通运输系统工程与信息 2018年第4期18卷 202-208页

作者：李航胡小兵中国民航大学中法联合空管应用数学研究中心天津300300 中国民航大学电子信息与自动化学院天津300300

脆弱性是表征1个系统面临灾害时行为表现的重要概念.要尽可能真实地反映民用航空网络面临空间灾害时的脆弱性水平,必须充分合理地考虑灾害影响在民用航空网络中的扩散效应,即灾害间接影响.在前期有关网络系统空间脆弱性研究的基础上,详... 详细信息

脆弱性是表征1个系统面临灾害时行为表现的重要概念.要尽可能真实地反映民用航空网络面临空间灾害时的脆弱性水平,必须充分合理地考虑灾害影响在民用航空网络中的扩散效应,即灾害间接影响.在前期有关网络系统空间脆弱性研究的基础上,详细地分析了灾害影响在民用航空网络中扩散的特点,确定了计算灾害间接影响的3个关键因素,即机场航班连接关系、机场间距离和机场失效门限,提出了改进的民用航空网络空间脆弱性模型.之后,以中国民用航空网络系统为例开展了案例研究,验证了所改进模型的有效性.

关键词：航空运输脆弱性空间灾害灾害扩散效应间接影响

Probing the Gamma-Ray Emission Region of Five TeV Flat Spectrum Radio Quasars

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Research in Astronomy and Astrophysics 2024年第6期24卷 156-169页

作者： hu-bing xiao Hai-Tao Cao Rui Xue Jin-Ting Cai Ge-Ge Wang Marina Manganaro Shao-hua Zhang Zhi-Hao Ouyang Li-Ping Fu Jun-hui Fan Shanghai Key Lab for Astrophysics Shanghai Normal UniversityShanghai 200234China School of Information Engineering Guangzhou Panyu PolytechnicGuangzhou 511483China Department of Physics Zhejiang Normal UniversityJinhua 321004China College of Mathematics and Physics Guangxi Minzu UniversityNanning 530006China Key Laboratory of Cosmology and Astrophysics(Liaoning) College of SciencesNortheastern UniversityShenyang 110819China Department of Physics University of RijekaRijeka 51000Croatia Center for Astrophysics Guangzhou UniversityGuangzhou 510006China Key Laboratory for Astronomical Observation and Technology of Guangzhou Guangzhou 510006China Astronomy Science and Technology Research Laboratory of Department of Education of Guangdong Province Guangzhou 510006China

The location ofγ-ray emission of blazars remains a contested topic,inspiring the development of numerous investigative techniques to address this *** this work,we analyzed Fermiγ-ray light curves in the GeV and MeV bands,employing the discrete cross-correlation function method to discern time lags between the two *** 4C+21.35,Ton 599,B21420+32,and PKS 1510-089,we identified a time lag spanning several days,while for PKS 1441+25,the time lag was not statistically *** results imply that the soft photons necessary for inverse Compton scattering predominantly originate from the dusty torus in the first four sources,whereas for PKS1441+25,they seem to be sourced mainly from the broad-line *** analysis of the opacity(τγγ)and the GeV spectra study supports the conclusion that the location of the dissipation region must be beyond the BLR to avoid significant ***,for PKS 1441+25,the emission region is also posited to lie outside yet proximate to the *** parameters of describing the emission region were obtained by fitting broadband spectral energy distribution with contemporaneous observation *** findings suggest that for the five TeV FSRQs,during Te V flaring events,the jet appears to maintain an equilibrium between the energy density of the magnetic field and that of the particles for all investigated sources,with the exceptions of 4C+21.35 and PKS1441+*** terms of the overall jet power,particle energy is the dominant contributor,and the observed blazar radiation cannot be solely attributed to the magnetic field,except in the case of 4C+***,magnetic reconnection is unlikely to be the primary mechanism behind particle acceleration in these systems.

关键词： galaxies:active gamma-rays:galaxies galaxies:jets

基于NSRFG方法的标准地貌风场大涡模拟研究

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工程力学 2020年第9期37卷 112-122页

作者：胡晓兵杨易华南理工大学亚热带建筑科学国家重点实验室广东广州510641

大涡模拟中入流湍流的准确模拟,是计算风工程领域当前研究的热点;准确定义与各类地貌大气边界层湍流特征相符的入流边界条件,是进行建筑结构风效应研究的前提(也是当前研究的难题)。该文在新提出的以湍流合成法为基础的LES入流湍流生成... 详细信息

大涡模拟中入流湍流的准确模拟,是计算风工程领域当前研究的热点;准确定义与各类地貌大气边界层湍流特征相符的入流边界条件,是进行建筑结构风效应研究的前提(也是当前研究的难题)。该文在新提出的以湍流合成法为基础的LES入流湍流生成技术——NSRFG方法上,研究了数学模型中若干参数的适当取值问题。通过数值分析对采样频率间距Δƒ、引入的时间尺度因子τ0和空间尺度因子θ、衰减系数cj及调谐因子γj等重要参数进行敏感性研究,分析了上述参数的取值对所生成湍流脉动风速功率谱、均方值和空间相关性等模拟结果的影响;在此基础上建议了一套与中国规范四类标准地貌风场相对应的参数表,从而建立基于该方法的"标准数值风场模型";通过实例对四类标准地貌边界层湍流风场进行数值模拟和平衡态检验。研究表明:上述关键参数的赋值对采用NSRFG方法进行大气边界层湍流风场的重构影响显著,该文基于NSRFG方法所建议的标准地貌数值风场模型,对研究者采用LES进行结构风工程的数值模拟研究具有一定的参考价值。

关键词：大涡模拟 NSRFG方法入流湍流生成敏感性研究脉动风速功率谱空间相关性