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Ground-layer adaptive optics for the New Vacuum Solar Telescope:Instrument description and first results

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Science China(Physics,Mechanics & Astronomy) 2023年第6期66卷 200-210页

作者： Lanqiang Zhang Hua Bao Xuejun Rao Youming Guo Libo Zhong xian ran Nanfei Yan Jinsheng Yang Cheng Wang Jiahui Zhou Ying Yang Yunyao Long Xinlong Fan Zhongyi Feng Donghong Chen Changhui Rao The Key Laboratory on Adaptive Optics Chinese Academy of SciencesChengdu 610209China The Laboratryon Adaptive Optics Institute of Optics and ElectronicsChinese Academyof SciencesChengdu 629China University of Chinese Academy of Sciences Beijing 100049China

Ground-layer adaptive optics(GLAO)has shown its potential for use in solar observation owing to its wide field-of-view(FOV)correction.A high-order GLAO system that consists of a multiple direction Shack-Hartmann wavefront sensor(WFS),a realtime controller with a multi-CPU processor,and a 151-element deformable mirror was developed for the 1-m New Vacuum Solar Telescope at Yunnan Observatories,Chinese Academy of Sciences.A hexagonal microlens with 9×8 subapertures is employed in the WFS.The detection FOV is 42′′×37′′,in which 9(3×3)guide regions are extracted for multiple direction wavefront sensing with a frame rate of up to 2200 Hz.To our knowledge,this is the first professional solar GLAO system used as a regularly operating instrument for scientific observations.Its installation and adjustment were performed in the summer of 2021.In this article,a detailed account of the GLAO system and its first light results and a comprehensive analysis of the performance of the GLAO system are provided.The results show that this system can effectively improve the imaging quality after compensating for the wavefront aberration due to ground-layer turbulence.

关键词： adaptive and segmented optics solar instruments astronomical observations

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我国高校图书馆开展社区阅读推广研究述评

文化创新比较研究 2024年第1期8卷 184-187页

作者：鲜冉中南财经政法大学图书馆湖北武汉430073

开展社区阅读推广是全民阅读浪潮下高校图书馆参与公共文化建设的重要举措。该文通过梳理我国高校图书馆开展社区阅读推广的相关研究,发现研究热点,总结研究成果,探讨研究空白,以期为未来高校图书馆开展社区阅读推广提供参考价值。研究... 详细信息

开展社区阅读推广是全民阅读浪潮下高校图书馆参与公共文化建设的重要举措。该文通过梳理我国高校图书馆开展社区阅读推广的相关研究,发现研究热点,总结研究成果,探讨研究空白,以期为未来高校图书馆开展社区阅读推广提供参考价值。研究发现,目前我国高校图书馆在社区阅读推广领域已形成初步的理论基础,具备一定的实践经验,相关研究聚焦在阅读推广的对象、阅读推广的模式、阅读推广的困境与对策等方面。同时也存在研究内容和研究方法较为单一的问题,在相关可行性、高校和社区需求、成效评估、国际经验等方面有待进一步探讨,同时需加强实证研究,规范研究方法。

关键词：高校图书馆大学图书馆社区阅读推广全民阅读社会服务公共文化

2019-2022年宁夏回族自治区人间布鲁氏菌分离株种型鉴定及分子特征分析

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疾病监测 2024年第3期39卷 279-284页

作者：高磊高建炜杨聪陈倩冼然赵瑜马江涛宁夏医科大学公共卫生学院宁夏银川750004 宁夏环境因素与慢性病控制重点实验室宁夏银川750004 宁夏回族自治区疾病预防控制中心宁夏银川750004

目的对2019-2022年宁夏回族自治区(宁夏)人间布鲁氏菌分离株进行种型和分子分型研究,掌握其分子遗传特征,为宁夏人间布鲁氏菌病(布病)的精准防控提供科学依据。方法采用AMOS聚合酶链式反应(AMOS-PCR)对布鲁氏菌分离株进行种的鉴定,运... 详细信息

目的对2019-2022年宁夏回族自治区(宁夏)人间布鲁氏菌分离株进行种型和分子分型研究,掌握其分子遗传特征,为宁夏人间布鲁氏菌病(布病)的精准防控提供科学依据。方法采用AMOS聚合酶链式反应(AMOS-PCR)对布鲁氏菌分离株进行种的鉴定,运用多位点可变数目串联重复序列分析(MLVA)对分离菌株进行分子分型,利用BioNumerics 7.6软件对MLVA结果进行聚类分析。结果 72株布鲁氏菌分离株经AMOS-PCR鉴定显示均为羊种布鲁氏菌。经MLVA分型,Panel1显示具有42、45、63共3个MLVA-8型。Panel2A显示均为41型(4-20-8),Panel2B显示具有高度多变性;72株菌被分为51个MLVA-16基因型,12个为共享基因型,其余39个为单一基因型。宁夏原州区的布鲁氏菌型别较为丰富,包含3种MLVA-8型别。本研究中的72株布鲁氏菌与多个省份的菌株存在18种完全相同的MLVA-16基因型,表明菌株不仅在宁夏广泛传播,在全国范围内也呈跨地区传播的特点。结论宁夏人间布病疫情极为严重,通过MLVA-16确定了宁夏布鲁氏菌分离株存在多种基因型,可为后续人间布病精准防控及流行病学溯源提供科学依据。

关键词：布鲁氏菌病 AMOS聚合酶链式反应多位点可变数目串联重复序列分析羊种布鲁氏菌

Cytoplasmic FKBPs are involved in molting and metamorphosis through regulating the nuclear localization of EcR

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Insect Science 2024年第3期31卷 759-772页

作者： xian Zhang Qiao-ran Wang Qian Wu Jun Gu Li-Hua Huang Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology School of Life SciencesSouth China Normal UniversityGuangzhouChina Guangmeiyuan R&D Center Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied TechnologySouth China Normal UniversityMeizhouChina

Molting and metamorphosis are important physiological processes in insects that are tightly controlled by ecdysone receptor(EcR)through the 20-hydroxyecdysone(20E)signaling pathway.EcR is a steroid nuclear receptor(SR).Several FK506-binding proteins(FKBPs)have been identified from the mammal SR complex,and are thought to be involved in the subcellular trafficking of SR.However,their roles in insects are poorly understood.To explore whether FKBPs are involved in insect molting or metamorphosis,we injected an FKBP inhibitor(FK506)into a lepidopteran insect,Spodoptera litura,and found that molting was inhibited in 61.11%of the larvae,and that the time for larvae to pupate was significantly extended.A total of 10 FKBP genes were identified from the genome of s.litura and were clustered into 2 distinct groups,according to their subcellular localization,with FKBP13 and FKBP14 belonging to the endoplasmic reticulum(ER)group and with the other members belonging to the cytoplasmic(Cy)group.All the CyFKBPs were significantly upregulated in the prepupal or pupal stages,with the opposite being observed for the ER group members.FK506 completely blocked the transfer of EcR to the nucleus under 20E induction,and significantly downregulated the transcriptional expression of many 20E signaling genes.A similar phenomenon was observed after RNA interference of2 CyFKBPs(FKBP45 and FKBP12b),but not for FKBP13.Taken together,our data indicate that the cytoplasmic FKBPs,especially FKBP45 and FKBP12b,mediate the nuclear localization of EcR,thereby regulating the 20E signaling and ultimately affecting molting and metamorphosis in insects.

关键词： EcR FKBP metamorphosis molting RNAi subcellular localization

Mechanical properties and microstructure of 3D-printed high Co–Ni secondary hardening steel fabricated by laser melting deposition

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International Journal of Minerals,Metallurgy and Materials 2017年第9期24卷 1027-1033页

作者： Hui-ping Duan Xiao Liu xian-zhe ran Jia Li Dong Liu School of Materials Science and Engineering Beihang UniversityBeijing 100191China National Engineering Laboratory of Additive Manufacturing for Large Metallic Components Beijing 100191China Engineering Research Center of Ministry of Education on Laser Direct Manufacturing for Large Metallic Component Beijing 100191China

The mechanical properties and microstructure of the 3D-printed high Co–Ni secondary hardening steel fabricated by the laser melting deposition technique was investigated using a material testing machine and electron microscopy. A microstructure investigation revealed that the samples consist of martensite laths, fine dispersed precipitates, and reverted austenite films at the martensite lath boundaries. The precipitates are enriched with Co and Mo. Because the sample tempered at 486°C has smaller precipitates and a higher number of precipitates per unit area, it exhibits better mechanical properties than the sample tempered at 498°C. Although the 3D-printed samples have the same phase constituents as Aer Met 100 steel, the mechanical properties are slightly worse than those of the commercial wrought Aer Met 100 steel because of the presence of voids.

关键词： laser deposition high strength steel mechanical properties microstructure

Template-free Synthesis of a Novel 3D Cage-like Nanostructured α-Fe_2O_3

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Chemical Research in Chinese Universities 2009年第6期25卷 963-965页

作者： YU ran-bo LI Zhen-min WANG Dan XING Chao-jian LAI Xiao-yong XING xian-ran Department of Physical Chemistry University of Science and Technology Beijing Beijing 100083 P. R. China State Key Laboratory of Multi-phase Complex System Institute of Process Engineering Chinese Academy of Sciences Beijing 100190 P. R. China Key Laboratory of Ecologic ＆ Recycle Metallurgy Ministry of Education University of Science and Technology Beijing Beijing 100083 P. R. China

Synthesis of inorganic nanostructures with specific size and well defined morphologies has attracted considerable attention due to their superior electrical, optical, magnetic, and chemical properties. Up to now, various kinds of metal oxide, sulfide, and hydrate with controlled hierarchical and complex morphologies have been successfully synthesized.

关键词： Template-free α-Fe2O3 Nanostructure

Recent Advances in Microbial Production of Terpenoids from Biomass-derived Feedstocks

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Chemical Research in Chinese Universities 2024年第1期40卷 20-28页

作者： CAO Yujin xian Mo CAS Key Laboratory of Biobased Materials Qingdao Institute of BioEnergy and Bioprocess TechnologyChinese Academy of SciencesQingdao 266101P.R.China Shandong Energy Institute Qingdao 266101P.R.China Qingdao New Energy Shandong Laboratory Qingdao 266101P.R.China

Terpenoids are a diverse class of natural products widely used as pharmaceuticals,perfumes,flavors,and biofuels.Traditionally,terpenoids are obtained from natural sources,such as plants,but their production is limited by the insufficiency of resources and low yields of extraction.Microbial production of terpenoids has emerged as a promising alternative due to that it is sustainable and easy to scale up.This review aims to summarize recent advances in microbial production of terpenoids from inexpensive biomass-derived feedstocks.Metabolic pathways and key enzymes involved in terpenoid biosynthesis are introduced.Microorganisms that can utilize low-cost lignocellulosic feedstocks for terpenoid production are highlighted.The challenges and prospects faced by microbial terpenoid production are proposed.We believe that continuous progress in the fields of biomass transformation and synthetic biology will ultimately achieve industrial production of microbial terpenoids.

关键词： Terpenoid Microbial production Biomass-derived feedstock Metabolic pathway

Track correlation algorithm based on CNN-LSTM for swarm targets

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Journal of Systems Engineering and Electronics 2024年第2期35卷 417-429页

作者： CHEN Jinyang WANG Xuhua CHEN xian Research Institute for National Defense Engineering Academy of Military SciencesLuoyang 471023China Information Engineering University Zhengzhou 450001China School of Computer Science and Technology Xidian UniversityXi’an 710071China

The rapid development of unmanned aerial vehicle(UAV) swarm, a new type of aerial threat target, has brought great pressure to the air defense early warning system. At present, most of the track correlation algorithms only use part of the target location, speed, and other information for correlation.In this paper, the artificial neural network method is used to establish the corresponding intelligent track correlation model and method according to the characteristics of swarm targets.Precisely, a route correlation method based on convolutional neural networks (CNN) and long short-term memory (LSTM)Neural network is designed. In this model, the CNN is used to extract the formation characteristics of UAV swarm and the spatial position characteristics of single UAV track in the formation,while the LSTM is used to extract the time characteristics of UAV swarm. Experimental results show that compared with the traditional algorithms, the algorithm based on CNN-LSTM neural network can make full use of multiple feature information of the target, and has better robustness and accuracy for swarm targets.

关键词： track correlation correlation accuracy rate swarm target convolutional neural network(CNN) long short-term memory(LSTM)neural network

Effect of Hot Isostatic Pressing on Fatigue Properties of Laser Melting Deposited AerMet100 Steel

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Journal of Iron and Steel Research(International) 2013年第11期20卷 79-84页

作者： CHENG Hao LIU Dong TANG Hai-bo ZHANG Shu-quan ran xian-zhe WANG Hua-ming Engineering Research Center of Ministry of Education on Laser Direct Manufacturing for Large Metallic Components Beihang University

The ultra-high strength steel AerMetl00 was fabricated .by laser melting deposition （LMD） process. The effect of hot isostatic pressing （HIP） on high-cycle fatigue properties of the LMD AerMet100 steel was investigated, and the influence of defects on fatigue behavior was discussed. Results showed that the LMD AerMetl00 steel had fine directionally solidified cellular dendrite structure and coarse columnar prior austenite grains. Metallurgical de fects such as gas pore and lack-of-fusion porosity were produced during the laser deposition process. After HIP treat- ment, the number and size of metallurgical defects had remarkably decreased. Moreover, high-cycle fatigue proper ties of the alloys after HIP treatment were superior to the as-deposited alloys.

关键词： laser melting deposition hot isostatic pressing AerMetl00 steel high cycle fatigue metallurgical defect