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Genome of Plant Maca （Lepidium meyenil） Illuminates Genomic Basis for High-Altitude Adaptation in the Central Andes

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Molecular Plant 2016年第7期9卷 1066-1077页

作者： Jing Zhang Yang Tian Liang Yan GuanghuiZhang Xiao Wang Yan Zeng Jiajin Zhang Xiao Ma Yuntao Tan Ni Long Yangzi Wang Yujin Ma Yuqi He Yu Xue Shumei Hao Shengchao Yang Wen Wang Liangsheng Zhang Yang Dong Wei Chen Jun Sheng College of Life science Huazhong University of Science and Technology Wuhan 430074 China College of Life sciences Jilin University Changchun 130012 China Key Laboratory of Pu-erh Tea science Ministry of Education Yunnan Agricultural University Kunming 650201 China Pu'er institute of Pu-erh Tea Pu'er 665000 China Yunnan research Center on Good Agricultural Practice for Dominant Chinese Medicinal Materials Yunnan Agricultural University Kunrning 650201 China State Key Laboratory of Genetic Resources and Evolution Kunming Institute of Zoology Chinese Academy of Sciences Kunming 650223 China University of Chinese Academy of sciences Beijing 100049 China School of science and Information Engineering Yunnan Agricultural University Kunming 650201 China College of Life science Kunming University of Science and Technology Kunming 650504 China Public Technical Service Center Kunming Institute of Zoology Chinese Academy of Sciences Kunming 650223 China Yunnan University Kunming 650091 China Center for Genomics and Biotechnology Haixia Institute of Science and Technology Fujian Agriculture and Forestry University Fuzhou 350002 China yunnan research institute for Local Plateau Agriculture and Industry Kunming 650201 China These authors contributed equally to this article.

Maca （Lepidium meyenii Walp, 2n = 8x = 64）, belonging to the Brassicaceae family, is an economic plant cultivated in the central Andes sierra in Peru （4000-4500 m）. Considering that the rapid uplift of the central Andes occurred 5-10 million years ago （Ma）, an evolutionary question arises regarding how plants such as maca acquire high-altitude adaptation within a short geological period. Here, we report the high-quality genome assembly of maca, in which two closely spaced maca-specific whole-genome duplications （WGDs; ~6.7 Ma） were identified. Comparative genomic analysis between maca and closely related Brassicaceae species revealed expansions of maca genes and gene families involved in abiotic stress response, hormone signaling pathway, and secondary metabolite biosynthesis via WGDs. The retention and subsequent functional divergence of many duplicated genes may account for the morphological and physiological changes （i.e., small leaf shape and self-fertility） in maca in a high-altitude environment. In addition, some duplicated maca genes were identified with functions in morphological adaptation （i.e., LEAF CURLING RESPONSIVENESS） and abiotic stress response （i.e., GL YClNE-RICH RNA-BINDING PROTEINS and DNA-DAMAGE-REPAIR/TOLERATION2） under positive selection. Collectively, the maca genome provides use- ful information to understand the important roles of WGDs in the high-altitude adaptation of plants in the Andes.

关键词： genome sequencing whole-genome duplication high-altitude adaptation Brassicaceae Lepidium,leaf morphogenesis self-incompatibility

Texturing and evaluation of concrete pavement surface:A state-of-the-art review

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Journal of Road Engineering 2023年第3期3卷 252-265页

作者： Zhen Leng Zepeng Fan Pengfei Liu Jonas Kollmann Markus Oeser Dawei Wang Xi Jiang Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHong KongChina School of transportation science and Engineering Harbin Institute of TechnologyHarbin 150090China institute of Highway Engineering RWTH Aachen UniversityAachen D52074Germany

Concrete pavement is accompanied by two major functional properties,namely noise emission and friction,which are closely related to pavement surface *** several technologies have been developed to mitigate tirepavement noise and improve driving friction by surface texturization,limited information is available to compare the advantages and disadvantages of different surface *** this study,a state-of-the-art and state-of-thepractice review is conducted to investigate the noise reduction and friction improvement technologies for concrete pavement *** commonly used tests for characterizing the surface texture,skid resistance,and noise emission of concrete pavement were first ***,the texturing methods for both fresh and hardened concrete pavement surfaces were discussed,and the friction,noise emission and durability performances of various surface textures were *** is found that the next generation concrete surface(NGCS)texture generally provides the best noise emission performance and excellent friction *** exposed aggregate concrete(EAC)and optimized diamond grinding textures are also promising ***,the technical parameters for the application of both diamond grinding and diamond grinding&grooving textures were recommended based on the authors'research and practical experience in Germany and the *** study offers a convenient reference to the pavement researchers and engineers who seek to quickly understand relevant knowledge and choose the most appropriate surface textures for concrete pavements.

关键词： Concrete pavement Surface texture Friction Noise emission Diamond grinding&grooving

Reconfigurable continuous-zoom metalens in visible band

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Chinese Optics Letters 2019年第11期17卷 69-74页

作者： Yuan Cui Guoxing Zheng Ming Chen Yilun Zhang Yan Yang Jin Tao Taotao He Zile Li Electronic Information School Wuhan UniversityWuhan 430072China NOEIC State Key Laboratory of Optical Comm unication Technologies and NetworksWuhan Research Institute of Posts and TelecommunicationsWuhan 430074China Photonics research Centre Guilin University of Electronic TechnologyGuilin 541004China Integrated Circuit Advanced Process Center Institute of Microelectronics of Chinese Academy of SciencesBeijing 100029China

The design of a conventional zoom lens is always challenging because it requires not only sophisticated optical design strategy, but also complex and precise mechanical structures for system adjustment. Here, we propose a continuous-zoom lens consisting of two chiral geometric metasurfaces with dielectric nanobrick arrays sitting on a transparent substrate. The metalens can continuously vary the focal length by rotating either of the two metasurfaces around its optical axis without changing any other conditions. Due to the polarization dependence of the geometric metasurface, the positive and negative polarities are interchangeable in one identical metalens only by changing the handedness of the incident circularly polarized light, which can generate varying focal lengths ranging from-∞ to +∞ in principle.

关键词： continuous visible rotating

End-to-End Joint Multi-Object Detection and Tracking for Intelligent transportation Systems

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Chinese Journal of Mechanical Engineering 2023年第5期36卷 280-290页

作者： Qing Xu Xuewu Lin Mengchi Cai Yu‑ang Guo Chuang Zhang Kai Li Keqiang Li Jianqiang Wang Dongpu Cao School of Vehicle and Mobility Tsinghua UniversityBeijing 100084China Horizon Information Technology Co. Ltd.Beijing 100096China School of transportation science and Engineering Beihang UniversityBeijing 100191China Dongfeng USharing Technology Co. Ltd.Wuhan 430000China Department of Mechanical and Mechatronics Engineering University of WaterlooWaterlooON N2L 3G1Canada

Environment perception is one of the most critical technology of intelligent transportation systems(ITS).Motion interaction between multiple vehicles in ITS makes it important to perform multi-object tracking(MOT).However,most existing MOT algorithms follow the tracking-by-detection framework,which separates detection and tracking into two independent segments and limit the global ***,a few algorithms have combined feature extraction into one network;however,the tracking portion continues to rely on data association,and requires com‑plex post-processing for life cycle *** methods do not combine detection and tracking *** paper presents a novel network to realize joint multi-object detection and tracking in an end-to-end manner for ITS,named as global correlation network(GCNet).Unlike most object detection methods,GCNet introduces a global correlation layer for regression of absolute size and coordinates of bounding boxes,instead of ofsetting *** pipeline of detection and tracking in GCNet is conceptually simple,and does not require compli‑cated tracking strategies such as non-maximum suppression and data *** was evaluated on a multivehicle tracking dataset,UA-DETRAC,demonstrating promising performance compared to state-of-the-art detectors and trackers.

关键词： Intelligent transportation systems Joint detection and tracking Global correlation network End-to-end tracking

A novel pore-fracture dual network modeling method considering dynamic cracking and its applications

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Petroleum research 2020年第2期5卷 164-169页

作者： Yukun Chen Kai Yan Jigang Zhang Runxi Leng Hongjie Cheng Xuhui Zhang Hongxian Liu Weifeng Lyu PetroChina Xinjiang Oilfield Research Institute of Exploration and DevelopmentKaramayXinjiang843000China College of Mechanical and transportation Engineering China University of Petroleum(Beijing)Beijing102249China institute of Mechanics Chinese Academy of SciencesBeijing100190China Department of Petroleum Engineering China University of Petroleum-Beijing at KaramayKaramayXinjiang834000China State Key Laboratory of Enhance Oil Recovery Research Institute of Petroleum Exploration and DevelopmentPetroChinaBeijing100083China

Unconventional reservoirs are normally characterized by dual porous media, which has both multi-scalepore and fracture structures, such as low permeability or tight oil reservoirs. The seepage characteristicsof such reservoirs is mainly determined by micro-fractures, but conventional laboratory experimentalmethods are difficult to measure it, which is attribute to the dynamic cracking of these *** emerging digital core technology in recent years can solve this problem by developing an accuratepore network model and a rational simulation approach. In this study, a novel pore-fracture dualnetwork model was established based on percolation theory. Fluid flow in the pore of two scales, microfracture and matrix pore, were considered, also with the impact of micro-fracture opening and closingduring flow. Some seepage characteristic parameters, such as fluid saturations, capillary pressure, relative permeabilities, displacement efficiency in different flow stage, can be predicted by proposedcalculating method. Through these work, seepage characteristics of dual porous media can be achieved.

关键词： Pore-fracture dual network model Micro-fracture Dynamic cracking Digital core Dimensionless parameters Seepage characteristics

Performance of Kilometer-Scale CARAS Precipitation Product Against Ground-based Observations During 2008-2021 over Hubei,China

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Journal of Tropical Meteorology 2024年第4期30卷 405-415页

作者： ZHU Chuan-dong LI Jin-xiao LI Ma-jun HE Fei CHENG Chi CHEN Yu CHEN Cheng LIAO Jie Hubei Meteorological Service Center Wuhan 430205 China China Meteorological Administration Basin Heavy Rainfall Key Laboratory/Hubei Key Laboratory for Heavy Rain Monitoring and Warning research Institute of Heavy RainChina Meteorological AdministrationWuhan 430205 China Shanghai Investigation Design and Research Institute Co.Ltd.Shanghai 200335 China Lancang Jingmai Airport of Yunnan Airport Group Limited Liability Company PuerYunnan 665600 China Public Meteorological Service Center China Meteorological AdministrationBeijing 100081 China Hubei Meteorological Society Wuhan 430074 China

Based on rain gauge data during 2008-2021 from national meteorological observation stations,this study investigated the performance of the precipitation field from the 1-km-resolution version of the China Atmospheric Realtime Analysis(CARAS)over Hubei from the perspective of climatology,multiple-time scale variations,as well as fusion accuracy and detection capability at multiple temporal *** results show that CARAS precipitation can reproduce the spatial distribution patterns of climatological seasonal precipitation and rainy days well over the whole of Hubei compared with observational(OBS)precipitation,albeit deviations exist between CARAS and OBS in terms of ***,high correlation and consistency between CARAS and OBS can be found in multiple-time scale variations over Hubei,with correlation coefficients of interannual,seasonal,and diurnal variation generally exceeding 0.85,0.98,and 0.95,***,CARAS has a relatively higher fusion accuracy in summer and winter,and stronger/weaker detection capability in spring/winter at a daily ***,the detection capability of CARAS at an hourly scale is weaker than that at a daily *** different precipitation intensity levels considered,CARAS daily precipitation shows relatively higher fusion accuracy in estimating moderate and heavy rain,and better detection capability in capturing no rain *** variations of accuracy metrics and detection metrics under different precipitation intensities at an hourly scale generally resemble those at a daily ***,CARAS precipitation at an hourly scale shows a relatively lower fusion accuracy and weaker detection capability compared with that at a daily *** paper provides an insight into the characteristics of systematic deviations in CARAS precipitation over Hubei,which will benefit relevant applications of CARAS in meteorological operations over Hubei and the improvement of CARAS in the future.

关键词： China Atmospheric Realtime Analysis kilometer-scale precipitation climatology multiple-time scale variations accuracy and detection capability

Diffusion and sound absorption properties of the quadratic residue diffuser structure with perforated panel

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Chinese Journal of Acoustics 2016年第3期35卷 255-264页

作者： CAI Jun BAO Fei WANG Yachen WANG Yanqin School of Environmental science and Engineering Shanghai JiaoTong University research institute of Highway Ministry of Transport

Acoustic structure study always is the academic research interest. Diffusion ab？sorbing structure（DiflFsorber） has good research value because it has both diflFusion property and sound absorption property. Quadratic residue diffusers（QRD） structure which had good diffusion property was combined with the perforated panel which had good sound absorption property in this study. According to standard AES-4id-2001, the diffusion experiments were carried out to study QRD structure and ones composited with perforated-panels which had1 mm-thickness and perforated percentage of 3%, 5%, 8% respectively. The polar coordinate diagrams of different structure were analyzed to derive the diffusion coefficients. Results showed that the composite structure still had good diffusion performance in the frequency range from100 Hz to 800 Hz. The reflection sound energy of composite structure reduced obviously in the perforated panel resonance frequency range where there was about 2 dB reduction *** study result can provide the reference for the design and development of diifsorber.

关键词： rate Diffusion and sound absorption properties of the quadratic residue diffuser structure with perforated panel

A modified stochastic model for LS+AR hybrid method and its application in polar motion short-term prediction

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Geodesy and Geodynamics 2024年第1期15卷 100-105页

作者： Fei Ye Yunbin Yuan State Key Laboratory of Geodesy and Earth's Dynamics Innovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan 430077China BeiDou High-precision Satellite Navigation and Location Service Hunan Engineering research Center Hunan Institute of Geomatics Sciences and TechnologyChangsha 410007China Hunan Continuously Operating Reference Stations(HNCORS)Data Center Hunan Institute of Geomatics Sciences and TechnologyChangsha 410007China

Short-term(up to 30 days)predictions of Earth Rotation Parameters(ERPs)such as Polar Motion(PM:PMX and PMY)play an essential role in real-time applications related to high-precision reference frame ***,least squares(LS)+auto-regressive(AR)hybrid method is one of the main techniques of PM ***,the weighted LS+AR hybrid method performs well for PM short-term ***,the corresponding covariance information of LS fitting residuals deserves further exploration in the AR *** this study,we have derived a modified stochastic model for the LS+AR hybrid method,namely the weighted LS+weighted AR hybrid *** using the PM data products of IERS EOP 14 C04,the numerical results indicate that for PM short-term forecasting,the proposed weighted LS+weighted AR hybrid method shows an advantage over both the LS+AR hybrid method and the weighted LS+AR hybrid *** to the mean absolute errors(MAEs)of PMX/PMY sho rt-term prediction of the LS+AR hybrid method and the weighted LS+AR hybrid method,the weighted LS+weighted AR hybrid method shows average improvements of 6.61%/12.08%and 0.24%/11.65%,***,for the slopes of the linear regression lines fitted to the errors of each method,the growth of the prediction error of the proposed method is slower than that of the other two methods.

关键词： Stochastic model LS+AR Short-term prediction The earth rotation parameter(ERP) Observation model

Strength properties and evolution laws of cracked sandstone samples in re-loading tests

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International Journal of Mining science and Technology 2020年第2期30卷 251-258页

作者： Yijiang Zong Lijun Han Qinbin Meng Yingchao Wang State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining&TechnologyXuzhou 221116China School of transportation Engineering Jiangsu Vocational Institute of Architectural TechnologyXuzhou 221116China

To study the strength properties and evolution laws of cracked sandstone samples in re-loading tests,strength and damage evolution properties of intact sandstone samples were first analyzed through the triaxial compression tests carried on TAW-2000 microcomputer control electro-hydraulic servo rock triaxial test *** evolution models were established based on dilatancy properties realizing the real-time and quantitative evaluation of samples damage state in loading *** this basis,samples with different damage were obtained by pre-peak,peak point,post-peak and residual strength stage unloading tests in the loading process of intact *** characteristics of the stress-strain curves and strength evolution laws were studied through the re-loading tests of samples with different damage under different stress *** experimental results showed that the slope of stress-strain curves,peak strength and residual strength of cracked samples increased linearly with confining pressure and decreased linearly with *** equivalent cohesion decreased with damage in the exponential decay *** mechanics properties of samples transformed from strain softening to strain hardening with damage.

关键词： Rock mechanics Damage Re-loading Strength characteristics Strain hardening