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Substitution of a Conserved Glycine in the PHR Domain of Arabidopsis CRYPTOCHROME 1 Confers a Constitutive Light Response

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Molecular Plant 2012年第1期5卷 85-97页

作者： nan-nan Gu Yan-Chun Zhang Hong-Quan Yang National Key Laboratory of Plant Molecular Genetics Institute of Plant Physiology and EcologyShanghai Institutes for Biological SciencesChinese Academy of SciencesShanghai 200032China Plant Science Institute School of Agriculture and BiologyShanghai Jiaotong UniversityShanghai 200240China

CRYPTOCHROMES （CRYs） are photolyase-like ultraviolet-A/blue light photoreceptors that mediate various light responses in plants. The signaling mechanism of Arabidopsis CRYs （CRY1 and CRY2） involves direct CRY-COP1 interaction. Here, we report that CRY1G380R, which carries a Gly-to-Arg substitution of the highly conserved G380 in the photo-lyase-related （PHR） domain of Arabidopsis CRY1, shows constitutive CRY1 photoreceptor activity in Arabidopsis. Transgenic plants overexpressing CRY1G380R display a constitutively photomorphogenic （COP） phenotype in darkness, as well as a dramatic early flowering phenotype under short-day light conditions （SD）. We further demonstrate that CRY1G380R expression driven by the native CRY1 promoter also results in a COP phenotype in darkness. Moreover, over- expression of either the Arabidopsis homolog CRY2G377R or the rice ortholog OsCRYlbG388R of CRY1G380R in Arabidopsis results in a COP phenotype in darkness. Cellular localization studies indicate that CRY1G380R co-localizes with COP1 in the same nuclear bodies （NBs） in vivo and inhibits the nuclear accumulation of COP1 in darkness. These results suggest that the conserved G380 may play a critical role in regulating the photoreceptor activity of plant CRYs and that CRY1G380R might constitutively phenocopy the photo-activated CRY1 in darkness and thus constitutively mediate CRY1 signaling.

关键词： Arabidopsis CRY1 CRy1G380R COP phenotype COP1.

Effects of solution and aging treatments on microstructures and mechanical properties of AZ61 magnesium alloy welded joints

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Rare Metals 2012年第1期31卷 12-16页

作者： Shen, Jun Xu, nan College of Materials Science & Engineering Chongqing University Chongqing 400044 China

The effects of solution and aging treatments on the microstructures and mechanical properties of tungsten inert gas arc welded AZ61 magne-sium alloy joints were investigated by microstructural observations,microhardness tests and tensile *** results showed that the solution treatment led to the β-Mg17Al12 particles dissolved into the α-Mg ***,the microhardness of the fusion zone and the ultimate tensile strength of the welded joints were the *** the increase of the aging temperature,the volume fraction of the β-Mg17Al12 particles in the fusion zone increased and this enhanced the microhardness of the fusion zone ***,the elongation of the welded joints was in-creased slightly with the increase of the volume fraction of the β-Mg17Al12 ***,the ultimate tensile strength of the welded joints increased at first and dropped at 190 ?C due to cracks formed at the boundaries of the β-Mg17Al12 particles.

关键词： magnesium alloy heat treatment microstructure mechanical properties

The Quasar Candidate Catalogs of DESI Legacy Imaging Survey Data Release 9

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Research in Astronomy and Astrophysics 2022年第9期22卷 267-277页

作者： Zizhao He nan Li Key Laboratory of Space Astronomy and Technology National Astronomical ObservatoriesBeijing 100101China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China

Quasars can be used to measure baryon acoustic oscillations at high redshift, which are considered as direct tracers of the most distant large-scale structures in the universe. It is fundamental to select quasars from observations before implementing the above research. This work focuses on creating a catalog of quasar candidates based on photometric data to provide primary priors for further object classification with spectroscopic data in the future, such as the Dark Energy Spectroscopic Instrument(DESI) Survey. We adopt a machine learning algorithm(Random Forest, RF) for quasar identification. The training set includes 651,073 positives and 1,227,172 negatives, in which the photometric information are from DESI Legacy Imaging Surveys(DESI-LIS) and Wide-field Infrared Survey Explore(WISE), and the labels are from a database of spectroscopically confirmed quasars based on Sloan Digital Sky Survey and the Set of Identifications& Measurements and Bibliography for Astronomical Data. The trained RF model is applied to point-like sources in DESI-LIS Data Release 9. To quantify the classifier’s performance, we also inject a testing set into the to-be-applied ***, we obtained 1,953,932 Grade-A quasar candidates and 22,486,884 Grade-B quasar candidates out of425,540,269 sources(~5.7%). The catalog covers ~99% of quasars in the to-be-applied data by evaluating the completeness of the classification on the testing set. The statistical properties of the candidates agree with that given by the method of color-cut selection. Our catalog can intensely decrease the workload for confirming quasars with the upcoming DESI data by eliminating enormous non-quasars but remaining high completeness. All data in this paper are publicly available online.

关键词： galaxies:quasars:general catalogs methods:statistical

Microwave-assisted One-pot Three-component Polymerization of Alkynes, Aldehydes and Amines toward Amino-functionalized Optoelectronic Polymers

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Chinese Journal of Polymer Science 2017年第2期35卷 269-281页

作者： tao jia nan-nan zheng wan-qing cai jie zhang lei ying 黄飞 yong cao Institute of Polymer Optoeleetronic Materials and Devices State Key Laboratory of Luminescent Materials and Devices South China University of Technology Guangzhou 510640 China

We present a microwave-assisted one-pot polymerization with three-components of alkynes, aldehydes and amines for the synthesis of new amino-functionalized optoelectronic polymers. The polymerization of diynes （la-lc）, dialdehydes （2a and 2b） and dibenzylamine catalyzed by InC13 was carried out smoothly within 1 h under microwave radiation, yielding four soluble polymers with high molecular weights. The resulting polymers P1 and P2 could be easily dissolved in alcohol and thus utilized as the cathode interlayer for polymer solar cells （PSCs）. Compared with the control device, the PSCs with P1 and P2 as the cathode interlayer and PTB7-Th：PC71BM as the photoactive layer exhibited significantly higher power conversion efficiencies （PCEs） of 9.49% and 9.16%, respectively. These results suggest that this polycoupling reaction is an efficient approach to construct three-component polymers for the practical applications.

关键词： One-pot three-component polymerization Polymer solar cells Cathode interlayer

Research on Voiceprint Recognition of Camouflage Voice Based on Deep Belief Network

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International Journal of Automation and computing 2021年第6期18卷 947-962页

作者： nan Jiang Ting Liu College of Public Security Information Technology and Intelligence Criminal Investigation Police University of ChinaShenyang 110854China College of Light Industry Liaoning UniversityShenyang 110036China

The problem of disguised voice recognition based on deep belief networks is studied. A hybrid feature extraction algorithm based on formants, Gammatone frequency cepstrum coefficients(GFCC) and their different coefficients is proposed to extract more discriminative speaker features from the original voice data. Using mixed features as the input of the model, a masquerade voice library is constructed. A masquerade voice recognition model based on a depth belief network is proposed. A dropout strategy is introduced to prevent overfitting, which effectively solves the problems of traditional Gaussian mixture models, such as insufficient modeling ability and low discrimination. Experimental results show that the proposed disguised voice recognition method can better fit the feature distribution, and significantly improve the classification effect and recognition rate.

关键词： Disguised voice recognition deep belief network feature extraction Gammatone frequency cepstrum coefficients(GFCC) dropout

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Chemical inequivalence behavior of the protons attached to the same carbon in ethylene-propylene copolymer(EPC)

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Chinese Chemical Letters 2008年第4期19卷 469-474页

作者： Peng Yu Bi Hui Ru Dong nan nan Wang College of Science Beijing University of Chemical TechnologyBeijing 100029PR China

Six ethylene-propylene copolymer samples with different structural parameters were analyzed by ^1H NMR,^13C NMR and ^1H-^13C COSY in this *** the aid of the ^1H-^13C COSY spectra of ethylene-propylene copolymer,the chemical inequivalence behavior of the protons attached to the same carbon in the ethylene-propylene copolymer could be observed. Four basic types of chemical bonds were divided,and two kinds of main conformations were proposed to explain this phenomenon. Based on the calculation of conformation distribution,it can be proved that the explanation of this phenomenon was reasonable.

关键词： Chemical inequivalence Ethylene-propylcne copolymer NMR

Battery Separators Functionalized with Edge-Rich MoS2/C Hollow Microspheres for the Uniform Deposition of Li2S in High-Performance Lithium-Sulfur Batteries

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nano-Micro Letters 2019年第3期11卷 104-118页

作者： nan Zheng Guangyu Jiang Xiao Chen Jiayi Mao nan Jiang Yongsheng Li Lab of Low-Dimensional Materials Chemistry Key Laboratory for Ultrafine Materials of Ministry of Education Shanghai Engineering Research Center of Hierarchical Nanomaterials School of Materials Science and Engineering East China University of Science and Technology

As promising energy storage systems,lithium-sulfur(Li-S)batteries have attracted significant attention because of their ultra-high energy ***,Li-S battery suffers problems related to the complex phase conversion that occurs during the charge-discharge process,particularly the deposition of solid Li2S from the liquid-phase polysulfides,which greatly limits its practical *** this paper,edge-rich MoS2/C hollow microspheres(Edg-MoS2/C HMs)were designed and used to functionalize separator for Li-S battery,resulting in the uniform deposition of *** microspheres were fabricated through the facile hydrothermal treatment of MoO3-aniline nanowires and a subsequent carbonization *** obtained Edg-MoS2/C HMs have a strong chemical absorption capability and high density of Li2S binding sites,and exhibit excellent electrocatalytic performance and can effectively hinder the polysulfide shuttle effect and guide the uniform nucleation and growth of ***,we demonstrate that the Edg-MoS2/C HMs can effectively regulate the deposition of Li2S and significantly improve the reversibility of the phase conversion of the active sulfur species,especially at high sulfur loadings and high *** a result,a cell containing a separator functionalized with Edg-MoS2/C HMs exhibited an initial discharge capacity of 935 mAh g-1 at 1.0 C and maintained a capacity of 494 mAh g-1 after 1000 cycles with a sulfur loading of 1.7 mg ***,at a high sulfur loading of 6.1 mg cm-2 and high rate of 0.5 C,the cell still delivered a high reversible discharge capacity of 478 mAh g-1 after 300 *** work provides fresh insights into energy storage systems related to complex phase conversions.

关键词： Edge-rich MoS2/C Hollow microspheres Li2S Lithium-sulfur batteries

面向DAG任务的分布式智能计算卸载和服务缓存联合优化

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中山大学学报（自然科学版）（中英文） 2025年第1期64卷 71-82页

作者：李云南子煜姚枝秀夏士超鲜永菊重庆邮电大学通信与信息工程学院重庆400065 重庆邮电大学软件工程学院重庆400065

建立了一种有向无环图(DAG,directed acyclic graph)任务卸载和资源优化问题,旨在应用最大可容忍时延等约束实现系统能耗最小化。考虑到网络中计算请求高度动态、完整的系统状态信息难以获取等因素,最后使用多智能体深度确定性策略梯度(... 详细信息

建立了一种有向无环图(DAG,directed acyclic graph)任务卸载和资源优化问题,旨在应用最大可容忍时延等约束实现系统能耗最小化。考虑到网络中计算请求高度动态、完整的系统状态信息难以获取等因素,最后使用多智能体深度确定性策略梯度(MADDPG,multi-agent deep deterministic policy gradient)算法来探寻最优的策略。相比于现有的任务卸载算法,MADDPG算法能够降低14.2%至40.8%的系统平均能耗,并且本地缓存命中率提高3.7%至4.1%。

关键词：移动边缘计算多智能体深度强化学习计算卸载资源分配服务缓存

High thermal conductivity dielectric polymers show record high capacitive performance at high temperatures

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National Science Review 2023年第11期10卷 85-86页

作者： Yang Shen Ce-Wen nan Tsinghua University State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and Engineering

Electrostatic capacitors are the most widely used components in modern electrical and electronic systems ranging from integrated circuits, electrical energy storage and pulsed power *** are the preferred dielectrics for electrostatic capacitors owing to their unique self-healing ability, high breakdown strength and ease of processing[1,2]. However, as the operating temperature increases, dielectric polymers exhibit substantially increased conduction loss,

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