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China CDC weekly 2021年第38期3卷 803-807,I0007,I0008页

作者： Juan Yang Zhigang Han Huifang Xu Hui Xing Peng Xu Weibin Cheng Yuzhou gu Fan Lyu The National Center for AIDS/STD Control and Prevention Chinese Center for Disease Control and PreventionBeijingChina Department of HIV/AIDS Control and Prevention Center for Disease Control and PreventionGuangzhouGuangdongChina.

Summary What is already known about this topic?Identifying the most influential spreaders in human immunodeficiency virus(HIV)transmission networks is crucial for developing effective prevention *** is added by this report?This study identified key nodes of the HIV molecular transmission network among men who have sex with men(MSM)by utilizing linkages between sequences to reconstruct the transmission network at the molecular level.

关键词： utilizing prevention network

Altitudinal variation of ecosystem CO_(2) fluxes in an alpine grassland from 3600 to 4200 m

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Journal of Plant Ecology 2009年第4期2卷 197-205页

作者： Mitsuru Hirota Pengcheng Zhang Song gu Mingyuan Du Ayako Shimono Haihua Shen Yingnian Li Yanhong Tang Graduate School of Life and Environmental Sciences University of Tsukuba1-1-1 TennohdaiTsukubaIbaraki 305-8572Japan Northwest Plateau Institute of Biology Chinese Academy of SciencesXining 810001People’s Republic of China National Institute for Agro-Environmental Sciences Kannondai 3-1-3TsukubaIbaraki 305-8604Japan National Institute for Environmental Studies Onogawa 16-2TsukubaIbaraki 305-8506Japan

Aims Recent studies have recognized the alpine grasslands on the Qinghai-Tibetan plateau as a significant sink for atmospheric CO_(2).The carbon-sink strength may differ among grassland ecosystems at various altitudes because of contrasting biotic and physical *** study aims(i)to clarify the altitudinal pattern of ecosystem CO_(2) fluxes,including gross primary production(GPP),daytime ecosystem respiration(Redaytime)and net ecosystem production(NEP),during the period with peak above-ground biomass;and(ii)to elucidate the effects of biotic and abiotic factors on the altitudinal variation of ecosystem CO_(2) *** Ecosystem CO_(2) fluxes and abiotic and biotic environmental factors were measured in an alpine grassland at four altitudes from 3600 to 4200 m along a slope of the Qilian Mountains on the northwestern Qinghai-Tibetan Plateau during the growing season of *** used a closed-chamber method combined with shade screens and an opaque cloth to measure several carbon fluxes,GPP,Redaytime and NEP,and factors,light-response curve for GPP and temperature sensitivity of ***-and below-ground biomasses and soil C and N contents at each measurement point were also *** Findings(i)Altitudinal pattern of ecosystem CO_(2) fluxes:The maximum net ecosystem CO_(2) flux(NEPmax),*** potential ecosystem CO_(2) sink strength,was markedly different among the four *** was higher at the highest and lowest sites,ap proximately7.460.9 and6.760.6 lmol CO_(2) m^(-2)s^(-1)(mean 6 standard error),respectively,but smaller at the intermediate altitude sites(3800 and 4000 m).The altitudinal pattern of maximum gross primary production was similar to that of *** Redaytime,however,was significantly higher at the lowest altitude(3.460.3 lmol CO_(2) m^(-2)s^(-1))than at the other three altitudes.(ii)Altitudinal variation of vegetation biomass:The aboveground biomass was higher at the highest altitude(154627 g DW m2)than

关键词： ecosystem respiration grazing gross primary production net ecosystem production Qinghai-Tibetan Plateau

Macadam’s theory in RGB laser display

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Chinese Physics B 2019年第6期28卷 227-231页

作者： guan Wang Yuhua Yang Tianhao Dong Chun gu Lixin Xu Zhongcan Ouyang Zuyan Xu Department of Optics and Optical Engineering University of Science and Technology of ChinaHefei 230026China

We have developed Macadam’s theory to deal with RGB laser display, which can well describe the color gamut display system varying with the laser bandwidth. By calculating the volume of R¨osch–Macadam color solid of laser display system under the Rec.2020 standard, we can obtain that the volume of chromatic stereoscopic at 30-nm laser spectral linewidth is about 90% of that at 1 nm laser spectral linewidth, which is important in laser display system to trade off the color gamut and the suppression of laser speckles. Moreover, we can also calculate the color gamut volume with different primary numbers and different primary wavelengths.

关键词： color gamut laser display optimal RGB value

Visible Light Responsive DNA Thermotropic Liquid Crystals Based on a Photothermal Effect of Gold Nanoparticles

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Journal of Analysis and Testing 2021年第2期5卷 181-187页

作者： Lei Zhang Yang Qu Yun Liu Yawen Deng Jingjing gu Zhongtao Wu Jiehua Lin Xiliang Luo Key Laboratory of Optic-Electric Sensing and Analytical Chemistry for Life Science MOEShandong Key Laboratory of Biochemical AnalysisCollege of Chemistry and Molecular EngineeringQingdao University of Science and TechnologyQingdao 266042China guangdong Key Laboratory for Research and Development of Natural Drugs Guangdong Medical UniversityZhanjiang 524023China

Solvent free DNA-surfactant melts are receiving continuous attractions in recent *** physical properties could be regulated via changing the alkyl chain length of *** an ideal external stimulus,light has been used in the regulation of mechanical properties of DNA thermotropic liquid crystal(TLC)containing an azobenzene motif,while in this case,the UV light is the only effective excitation ***,in comparison with visible light,UV light causes damage to DNA and has low tissue-penetration efficiency *** this work,a new type of DNA-didodecyldimethylammonium bromide(DNA-DDAB)TLCs fabricating with gold nanoparticles(AuNPs)was *** visible light-induced photothermal effect of AuNPs could change the mechanical properties of AuNPs/DNA-DDAB TLCs,as shown by clearly boundary motion activity and viscoelasticity ***,the ratio of AuNPs and charge stoichiometry of DNA:DDAB also affected photocurrent generation property of these DNA *** development of this visible light responsive DNA melt might facilitate the related studies in biomedicine and biomaterials.

关键词： Light responsive material Thermotropic liquid crystal Gold nanoparticle DNA melt Photothermal effect

Reproducibility of optical quality parameters measured at objective and subjective best focuses in a doublepass system

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International Journal of Ophthalmology(English edition) 2015年第5期8卷 1043-1050页

作者： Ai-Lian Hu Li-Ya Qiao Ye Zhang Xiao-gu Cai Lei Li Xiu-Hua Wan Beijing Institute of Ophthalmology Beijing Tongren Eye CenterBeijing Tongren HospitalCapital Medical UniversityBeijing Ophthalmology & Vision Science Key Lab

AIMTo evaluate intra-session repeatability and reproducibility of optical quality parameters measured at objective and subjective best focuses in a double-pass *** Chinese healthy adults (19 to 40 years old) meeting our inclusion criterion were enrolled in the study. After a basic eye examination, two methods of optical quality measurement, based on subjective and objective best focuses were performed using the Optical Quality Analysis System (OQAS) with an artificial pupil diameter of 4.0 *** each method, three consecutive measurements of the following parameters: the modulation transfer function cutoff frequency (MTFcutoff), the Strehl2D ratio, the OQAS values (OVs) at contrasts of 100%, 20%, 9% and the objective scatter index (OSI) were performed by an experienced examiner. The repeatability of each method was evaluated by the repeatability limit (RL) and the coefficient of repeatability (COR). Reproducibility of the two methods was evaluated by intra-class correlation coefficient (ICC) and the 95% limits of agreement (Bland and Altman analysis). Thirty subjects, seven females and twenty three males, of whom 15 right eyes and 15 left eyes were selected randomly for recruitment in the study. The RLs (percentage) for the six parameters measured at objective focus and subjective focus ranged from 8.44% to 15.13% and 10.85% to 16.26%, respectively. The CORs for the two measurement methods ranged from 8.27% to 14.83% and 10.63% to 15.93%, respectively. With regard to reproducibility, the ICCs for the six parameters of OQAS ranged from 0.024 to 0.276. The 95% limits of agreement obtained for the six parameters (in comparison of the two methods) ranged from -0.57 to 42.18 (MTFcutoff), -0.01 to 0.23 (Strehl2D ratio), -0.02 to 1.40 (OV100%), -0.10 to 1.75 (OV20%), -0.14 to 1.80 (OV9%) and -1.46 to 0.18 (OSI).CONCLUSIONMeasurements provided by OQAS with either method sh

关键词： optical quality double-pass system best focus repeatability reproducibility

Ultrabroad-band,white light emission from carbon dot-based materials with hybrid fluorescence/phosphorescence for single component white light-emitting diodes

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Chinese Chemical Letters 2023年第5期34卷 444-448页

作者： Yuchen Li Qijun Li Shuai Meng Yukun Qin Dengke Cheng Hailing gu Zifei Wang Yunxia Ye Jing Tan Institute of Micro-nano Optoelectronics and Terahertz Technology School of Mechanical EngineeringJiangsu UniversityZhenjiang 212013China School of Mechanical Engineering Yangzhou UniversityYangzhou 225009China Institute for Energy Research Jiangsu UniversityZhenjiang 212013China School of Materials Science&Engineering Qilu University of Technology(Shandong Academy of Sciences)Ji'nan 250300China

Benefiting from the large Stokes shift between fluorescence and phosphorescence,fluorescence/phosphorescence dual-emitting carbon dots(CDs)have gradually entered at the stage of single-phase white light-emitting diodes(WLEDs)as‘green material'.However,most of the developed dual-emitting CDs have weak phosphorescence,short emission wavelength and narrow emission band,resulting in relatively bluish white light emission and low color rendering index(CRI).Herein,an ultrabroad-band fluorescence/phosphorescence dual-emitting CD-based material(UB-CD@BA)is prepared by thermal treatment of boric acid(BA)and CDs with large conjugated *** stable covalent bonding between CDs and BA,as well as three-dimensional spatial restriction effect of selfpolymerization BA molecules around CDs during long-term heating efficiently rigidified the single/triplet excited states of CDs from non-radiative deactivation,thus producing strong dual emissive materials with the high phosphorescence quantum yield of 21%.Remarkable,the prepared UB-CD@BA powders exhibit bright pure white light emission with Commission Internationale de l'Eclairage(CIE)coordinates of(0.32,0.33)and the highest reported full width at half maximum of 250 *** on the unique characteristics of UB-CD@BA,it was used as a color conversion layer to prepare a WLED with CIE coordinates of(0.35,0.33)and the CRI value of 87.

关键词： Carbon dots White LEDs Fluorescence/phosphorescence dual emission Ultrabroad-band Conjugation structure

Low-temperature processed inorganic hole transport layer for efficient and stable mixed Pb-Sn low-bandgap perovskite solar cells

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Science Bulletin 2019年第19期64卷 1399-1401页

作者： Qiaolei Han Ying Wei Renxing Lin Zhimin Fang Ke Xiao Xin Luo Shuai gu Jia Zhu Liming Ding Hairen Tan National Laboratory of Solid State Microstructures Jiangsu Key Laboratory of Artificial Functional MaterialsCollege of Engineering and Applied SciencesNanjing UniversityNanjing 210093China Center for Excellence in Nanoscience(CAS) Key Laboratory of Nanosystem and Hierarchical Fabrication(CAS)National Center for Nanoscience and TechnologyBeijing 100190China

Metal halide perovskite solar cells(PSCs)have attracted tremendous attention as an emerging photovoltaic technology due to their high efficiency,low cost and ease of fabrication from earth-abundant materials[1,2].The power conversion efficiencies(PCEs)have been rapidly boosted from 3.8%in the pioneer’s work to a certified 24.2%nowadays in just ten years[3].The PCE breakthroughs in PSCs have mostly adopted full lead-based perovskites(APbX3)with bandgaps of 1.5–1.6 eV.

关键词： Low-temperature PEDOT Pb solar cells

Razumikhin-Type Theorems on p-th Moment Stability for Stochastic Switching Nonlinear Systems with Delay

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Journal of Applied Mathematics and Physics 2016年第7期4卷 1237-1244页

作者： Haibo gu Caixia Gao School of Mathematical Sciences Inner Mongolia University Hohhot China

This paper mainly tends to utilize Razumikhin-type theorems to investigate p-th moment stability for a class of stochastic switching nonlinear systems with delay. Based on the Lyapunov-Razumik- hin methods, some sufficient conditions are derived to check the stability of stochastic switching nonlinear systems with delay. One numerical example is provided to demonstrate the effectiveness of the results.

关键词： Stochastic Switching Delay System p-th Moment Stability Lyapunov-Razumikhin Approach

Light-Emitting Diodes Based on Two-Dimensional Nanoplatelets

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Energy Material Advances 2022年第1期2022卷 320-343页

作者： Yating guo Feng Gao Pan Huang Rong Wu Wanying gu Jing Wei Fangze Liu Hongbo Li Beijing Key Laboratory of Construction-Tailorable Advanced Functional Materials and Green ApplicationsExperimental Center of Advanced MaterialsSchool of Materials Science and EngineeringBeijing Institute of TechnologyBeijing 100081China Advanced Research Institute of Multidisciplinary Sciences Beijing Institute of TechnologyBeijing 100081China

Colloidal semiconductor nanocrystals(NCs)attract significant interest in recent years due to their narrow and tunable emission wavelength in the visible range,as well as high photoluminescence quantum yield(PLQY),which are highly desired in display *** high-quality NCs have been recognized as vital luminescent materials in realizing next-generation display *** further development,NCs with near-unity PLQY have been successfully synthesized through engineering of the core/shell ***,as the external quantum efficiency(EQE)of the nanocrystal light-emitting diodes(LEDs)approaches the theoretical limit of about 20%,the low out-coupling factor proposes a challenge of enhancing the performance of a device when using the spherical ***,the anisotropic NCs like nanoplatelets(NPLs)are proposed as promising solutions to improve the performance of nanocrystal *** this review,we will summarize the synthetic strategies of twodimensional(2D)NPLs at ***,we will introduce fundamental concepts of LEDs,the main approaches to realize LEDs based on nanoplatelets,and the recent ***,the challenges and opportunities of LEDs based on anisotropic NCs are also presented.

关键词： tunable quantum anisotropic

Bi-GRU Relation Extraction Model Based on Keywords Attention

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Data Intelligence 2022年第3期4卷 552-572页

作者： Yuanyuan Zhang Yu Chen Shengkang Yu Xiaoqin gu Mengqiong Song Yu Peng Jianxia Chen Qi Liu Technical Training Center of State Grid Hubei Electric Power Co. Ltd.Wuhan 430070China Hubei University of Technology School of Computer ScienceWuhan 430068China

Relational extraction plays an important role in the field of natural language processing to predict semantic relationships between entities in a sentence. Currently, most models have typically utilized the natural language processing tools to capture high-level features with an attention mechanism to mitigate the adverse effects of noise in sentences for the prediction results. However, in the task of relational classification, these attention mechanisms do not take full advantage of the semantic information of some keywords which have information on relational expressions in the sentences. Therefore, we propose a novel relation extraction model based on the attention mechanism with keywords, named Relation Extraction Based on Keywords Attention(REKA). In particular, the proposed model makes use of bi-directional GRU(Bi-GRU) to reduce computation, obtain the representation of sentences, and extracts prior knowledge of entity pair without any NLP tools. Besides the calculation of the entity-pair similarity, Keywords attention in the REKA model also utilizes a linear-chain conditional random field(CRF) combining entity-pair features, similarity features between entity-pair features, and its hidden vectors, to obtain the attention weight resulting from the marginal distribution of each word. Experiments demonstrate that the proposed approach can utilize keywords incorporating relational expression semantics in sentences without the assistance of any high-level features and achieve better performance than traditional methods.

关键词： Relation extraction Bi-GRU CRF keywords attention Hidden similarity