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Four Late-type Galaxies with Double Radio Lobes and Properties of Such Galaxies

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Research in Astronomy and Astrophysics 2024年第4期24卷 84-90页

作者： Z.S.Yuan X.Y.Gao Z.L.Wen J.L.Han National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China cas key laboratory of fast National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China School of Astronomy and Space Sciences University of Chinese Academy of SciencesBeijing 100049China

The triggering mechanism for radio lobes from late-type galaxies is not fully understood.More samples are desired for a thorough investigation and statistics.By utilizing the optical data from the newly released Dark Energy Spectroscopic Instrument imaging surveys and the radio sources from the NRAO VLA Sky Survey and the Faint Images of the Radio Sky at Twenty-centimeter,we identify four Late-type Galaxies with double Radio Lobes(La GRLs):J0217-3645,J0947+6220,J1412+3723 and J1736+5108.Including previously known La GRLs,we confirm the correlation between radio power P_(1.4GHz)and stellar mass M_(*)of host galaxies.Most(25/35)La GRLs belong to the blue cloud galaxies,while the newly identified cases in this work are located within the region of the red sequence.We find a clear correlation between the differential radio power,i.e.,the offset from the P_(1.4GHz)-M_(*)relation,and the galaxy color,indicating that bluer galaxies at a fixed M_(*)tend to host more powerful radio lobes.Furthermore,the majority(31/36)of La GRLs are either located in a galaxy group or displaying a disturbed morphology.We suggest that all of the galaxy mass,color and surrounding environment could play important roles in triggering radio lobes in late-type galaxies.

关键词： galaxies:active galaxies:jets galaxies:spiral radio continuum:galaxies

Wood of trees:Cellular structure,molecular formation,and genetic engineering

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Journal of Integrative Plant Biology 2024年第3期66卷 443-467页

作者： Yingying Zhu Laigeng Li State key laboratory of Herbage Improvement and Grassland Agro-ecosystems and College of Ecology Lanzhou UniversityLanzhou 730000China National key laboratory of Plant Molecular Genetics CAS Center for Excellence in Molecular Plant SciencesChinese Academy of SciencesShanghai 200032China

Wood is an invaluable asset to human society due to its renewable nature,making it suitable for both sustainable energy production and material manufacturing.Additionally,wood derived from forest trees plays a crucial role in sequestering a significant portion of the carbon dioxide fixed during photosynthesis by terrestrial plants.Nevertheless,with the expansion of the global population and ongoing industrialization,forest coverage has been substantially decreased,resulting in significant challenges for wood production and supply.Wood production practices have changed away from natural forests toward plantation forests.Thus,understanding the underlying genetic mechanisms of wood formation is the foundation for developing high-quality,fast-growing plantation trees.Breeding ideal forest trees for wood production using genetic technologies has attracted the interest of many.Tremendous studies have been carried out in recent years on the molecular,genetic,and cell-biological mechanisms of wood formation,and considerable progress and findings have been achieved.These studies and findings indicate enormous possibilities and prospects for tree improvement.This review will outline and assess the cellular and molecular mechanisms of wood formation,as well as studies on genetically improving forest trees,and address future development prospects.

关键词： cambium cell wall Populus wood formation xylem

Applying Hybrid Clustering in Pulsar Candidate Sifting with Multi-modality for fast Survey

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Research in Astronomy and Astrophysics 2024年第3期24卷 283-296页

作者： Zi-Yi You Yun-Rong Pan Zhi Ma Li Zhang Shuo Xiao Dan-Dan Zhang Shi-Jun Dang Ru-Shuang Zhao Pei Wang Ai-Jun Dong Jia-Tao Jiang Ji-Bing Leng Wei-An Li Si-Yao Li School of Physics and Electronic Science Guizhou Normal UniversityGuiyang 550025China Guizhou Provincial key laboratory of Radio Astronomy and Data Processing Guizhou Normal UniversityGuiyang 550025China College of Big Data and Information Engineering Guizhou UniversityGuiyang 550025China cas key laboratory of fast National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China key laboratory of Information and Computing Guizhou Province Guizhou Normal UniversityGuiyang 550001China School of Big data and Computer Science Guizhou Normal UniversityGuiyang 550025China Guizhou Software Engineering Research Center Guiyang 550000China

Pulsar search is always the basis of pulsar navigation,gravitational wave detection and other research topics.Currently,the volume of pulsar candidates collected by the Five-hundred-meter Aperture Spherical radio Telescope(fast)shows an explosive growth rate that has brought challenges for its pulsar candidate filtering system.Particularly,the multi-view heterogeneous data and class imbalance between true pulsars and non-pulsar candidates have negative effects on traditional single-modal supervised classification methods.In this study,a multi-modal and semi-supervised learning based on a pulsar candidate sifting algorithm is presented,which adopts a hybrid ensemble clustering scheme of density-based and partition-based methods combined with a feature-level fusion strategy for input data and a data partition strategy for parallelization.Experiments on both High Time Resolution Universe SurveyⅡ(HTRU2)and actual fast observation data demonstrate that the proposed algorithm could excellently identify pulsars:On HTRU2,the precision and recall rates of its parallel mode reach0.981 and 0.988 respectively.On fast data,those of its parallel mode reach 0.891 and 0.961,meanwhile,the running time also significantly decreases with the increment of parallel nodes within limits.Thus,we can conclude that our algorithm could be a feasible idea for large scale pulsar candidate sifting for fast drift scan observation.

关键词： methods data analysis-surveys-methods numerical

V0405 Dra: A New Deep and Low Mass Ratio Contact Binary with Extremely fast Decrease in the Orbital Period

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Research in Astronomy and Astrophysics 2024年第6期24卷 289-295页

作者： Chao-Yue Li Lin-Qiao Jiang Jie Zheng Yi-Man Liu Xiao-Yu Long Min Sun Han-Lu Zhang Xiao-Man Tian School of Science Leshan Normal University Center for Applied Optics Research Leshan Normal University key laboratory of Detection and Application of Space Effect in Southwest Sichuan cas key laboratory of Optical Astronomy National Astronomical Observatories Chinese Academy of Sciences School of Aeronautics Shandong Jiaotong University

V0405 Dra is a W UMa-type binary star. Based on the TESS data, we have conducted an orbital period study and performed a light curve analysis for the system. The orbital period study reveals that the O-C curve for V0405 Dra exhibits secular decrease at an extremely high rate of d P/dt =-2.71 × 10-6day year-1, along with periodic variations characterized by an amplitude of A3= 0.0032 day and a period of P3= 1.413 years. The orbital periodic change is possibly due to the light-travel time effect resulting from an additional third body in the system, for which we estimate a minimum mass of M3= 0.77M⊙. By employing the 2013 version of the Wilson-Devinney（W-D） method to synthesize a light curve, we derived photometric solutions indicating that V0405 Dra is a new deep（ f = 68.7%） and low-mass ratio（q = 0.175） contact binary. The fast decrease in its orbital period is likely caused by mass transfer from the more massive primary star to the less massive secondary star, or due to angular momentum loss. With further mass transfer and loss of angular momentum, the binary will gradually evolve into a tighter contact configuration, eventually leading to a merger into a single star, following the evolutionary paths suggested for such deep and low mass ratio contact binaries.

关键词： (stars:) binaries (including multiple): close (stars:) binaries: eclipsing stars: individual (V0405 Dra)

Crowdsourcing RTK:a new GNSS positioning framework for building spatial high-resolution atmospheric maps based on massive vehicle GNSS data

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Satellite Navigation 2024年第1期5卷 91-108页

作者： Hongjin Xu Xingyu Chen Jikun Ou Yunbin Yuan State key laboratory of Geodesy and Earth’s Dynamics Innovation Academy for Precision Measurement Science and Technology(APM)Chinese Academy of Sciences(CAS)Wuhan430071China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijingChina

High-quality spatial atmospheric delay correction information is essential for achieving fast integer ambiguity resolution(AR)in precise positioning.However,traditional real-time precise positioning frameworks(i.e.,NRTK and PPP-RTK)depend on spatial low-resolution atmospheric delay correction through the expensive and sparsely distributed CORS network.This results in limited public appeal.With the mass production of autonomous driving vehicles,more cost-effective and widespread data sources can be explored to create spatial high-resolution atmospheric maps.In this study,we propose a new GNSS positioning framework that relies on dual base stations,massive vehicle GNSS data,and crowdsourced atmospheric delay correction maps(CAM).The map is easily produced and updated by vehicles equipped with GNSS receivers in a crowd-sourced way.Specifically,the map consists of between-station single-differenced ionospheric and tropospheric delays.We introduce the whole framework of CAM initialization for individual vehicles,on-cloud CAM maintenance,and CAM-augmented user-end positioning.The map data are collected and preprocessed in vehicles.Then,the crowdsourced data are uploaded to a cloud server.The massive data from multiple vehicles are merged in the cloud to update the CAM in time.Finally,the CAM will augment the user positioning performance.This framework forms a beneficial cycle where the CAM’s spatial resolution and the user positioning performance mutually improve each other.We validate the performance of the proposed framework in real-world experiments and the applied potency at different spatial scales.We highlight that this framework is a reliable and practical positioning solution that meets the requirements of ubiquitous high-precision positioning.

关键词： New GNSS positioning framework Spatial high-resolution atmospheric delay correction Crowdsourced atmospheric delay correction maps Crowdsourced ionosphere Crowdsourced troposphere Ubiquitous

Leaf habit differentiation explains trait tradeoffs across savanna woody plants

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Forest Ecosystems 2024年第3期11卷 287-295页

作者： Yangsiding Wang Da Yang German Vargas G. Guangyou Hao Jennifer S.Powers Yan Ke Qin Wang Yunbing Zhang Jiaolin Zhang cas key laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMenglaYunnan 666303China University of Chinese Academy of Sciences Beijing 100049China School of Biological Sciences University of UtahSalt Lake CityUT 84112USA cas key laboratory of Forest Ecology and Management Institute of Applied EcologyChinese Academy of SciencesShenyang 110016China Department of Ecology Evolution and BehaviorUniversity of MinnesotaSt PaulMN 55108USA

Identifying how leaf habit subdivisions link to the fast–slow and avoidance–tolerance trait tradeoffs can provide new insight into divergence in ecophysiological strategies among plant functional groups. Here, we tested a hypothesis that the differentiation across deciduous, semi-deciduous and evergreen woody species contributes to physiological trait tradeoffs in a dry-hot valley savanna. We investigated 11 photosynthetic, morphological and hydraulic traits of 24 species including 8 deciduous, 10 semi-deciduous and 6 evergreen species. Deciduous species were grouped in the fast and avoidance side associated with high values of maximum photosynthetic rates,stomatal conductance and leaf size, while evergreen species were grouped in the slow and tolerance side associated with high photosynthetic water use efficiency, leaf mass per area, sapwood density, Huber value, leaf water potential at turgor loss point and water potential causing 50% loss of stem hydraulic conductance. Semideciduous species generally had intermediate trait values and represented different physiological characteristics when compared to deciduous and evergreen species. The physiological trait tradeoffs showed a close linkage to the differentiation of these three leaf habits. Our findings clearly reveal trait tradeoffs related to fast–slow and avoidance–tolerance strategies among diverse savanna plants, suggesting a syndrome in multiple ecophysiology strategies across different leaf habits.

关键词： Dry-hot habitat Gas exchange Hydraulics Phenology Tolerance Valley savanna

High-performance liquid metal electromagnetic actuator fabricated by femtosecond laser

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International Journal of Extreme Manufacturing 2024年第2期6卷 511-521页

作者： Yiyu Chen Hao Wu Rui Li Shaojun Jiang Shuneng Zhou Zehang Cui Yuan Tao Xinyuan Zheng Qianqian Zhang Jiawen Li Guoqiang Li Dong Wu Jiaru Chu Yanlei Hu cas key laboratory of Mechanical Behavior and Design of Materials Key Laboratory of Precision Scientific Instrumentation of Anhui Higher Education InstitutesDepartment of Precision Machinery and Precision InstrumentationUniversity of Science and Technology of ChinaHefei 230027People’s Republic of China key laboratory of Testing Technology for Manufacturing Process of Ministry of Education Southwest University of Science and TechnologyMianyang 621010People’s Republic of China Department of Mechanical Engineering The University of Hong KongHong Kong Special Administrative Region of ChinaPeople’s Republic of China

Small-scale electromagnetic soft actuators are characterized by a fast response and simplecontrol,holding prospects in the field of soft and miniaturized robotics.The use of liquid metal(LM)to replace a rigid conductor inside soft actuators can reduce the rigidity and enhance the actuation performance and robustness.Despite research efforts,challenges persist in the flexible fabrication of LM soft actuators and in the improvement of actuation performance.To address these challenges,we developed a fast and robust electromagnetic soft microplate actuator based on a laser-induced selective adhesion transfer method.Equipped with unprecedentedly thin LM circuit and customized low Young’s modulus silicone rubber(1.03 kPa),our actuator exhibits an excellent deformation angle(265.25?)and actuation bending angular velocity(284.66 rad·s^(-1)).Furthermore,multiple actuators have been combined to build an artificial gripper with a wide range of functionalities.Our actuator presents new possibilities for designing small-scaleartificial machines and supports advancements in ultrafast soft and miniaturized robotics.

关键词： soft actuators femtosecond laser liquid metal

Revealing the key role of non-solvating diluents for fast-charging and low temperature Li-ion batteries

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Journal of Energy Chemistry 2024年第7期94卷 171-180页

作者： Yuping Zhang Siyin Li Junkai Shi Jiawei Lai Ziyue Zhuang Jingwen Liu Wenming Yang Liang Ma Yue-Peng Cai Jjian Xu Qifeng Zheng School of Chemistry Guangzhou Key Laboratory of Materials for Energy Conversion and StorageSouth China Normal UniversityGuangzhou 510006GuangdongChina Guangzhou Foreign Language School Guangzhou 511455GuangdongChina Department of ChemistryCity University of Hong KongHong Kong 999077China

fast-charging and low temperature operation are of vital importance for the further development of lithium-ion batteries(LIBs),which is hindered by the utilization of conventional carbonate-based elec-trolytes due to their slow kinetics,narrow operating temperature and voltage range.Herein,an acetoni-trile(AN)-based localized high-concentration electrolyte(LHCE)is proposed to retain liquid state and high ionic conductivity at ultra-low temperatures while possessing high oxidation stability.We originally reveal the excellent thermal shielding effect of non-solvating diluent to prevent the aggregation of Lit sol-vates as temperature drops,maintaining the merits of fast Li transport and facile desolvation as at room temperature,which bestows the graphite electrode with remarkable low temperature performance(264 mA h g^(-1) at-20 C).Remarkably,an extremely high capacity retention of 97%is achieved for high-voltage high-energy graphitellNCM batteries after 250 cycles at-20 C,and a high capacity of 110 mA h g^(-1)(71%of its room-temperature capacity)is retained at-30°C.The study unveils the key role of the non-solvating diluents and provides instructive guidance in designing electrolytes towards fast-charging and low temperature LIBs.

关键词： Li-ion battery fast-charging Low temperature Non-solvating diluent Shielding effect

IP-Pealing: A Robust Network Flow Watermarking Method Based on IP Packet Sequence

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Chinese Journal of Electronics 2024年第3期33卷 694-707页

作者： Wangxin FENG Xiangyang LUO Tengyao LI Chunfang YANG State key laboratory of Mathematical Engineering and Advanced Computing key laboratory of Cyberspace Situation Awareness of Henan Province

Network flow watermarking(NFW) is usually used for flow correlation.By actively modulating some features of the carrier traffic,NFW can establish the correspondence between different network nodes.In the face of strict demands of network traffic tracing,current watermarking methods cannot work efficiently due to the dependence on specific protocols,demand for large quantities of packets,weakness on resisting network channel interferences and so on.To this end,we propose a robust network flow watermarking method based on IP packet sequence,called as IP-Pealing.It is designed to utilize the packet sequence as watermark carrier with IP identification field which is insensitive to time jitter and suitable for all IP based traffic.To enhance the robustness against packet loss and packet reordering,the detection sequence set is constructed in terms of the variation range of packet sequence,correcting the possible errors caused by the network transmission.To improve the detection accuracy,the long watermark information is divided into several short sequences to embed in turn and assembled during detection.By a large number of experiments on the Internet,the overall detection rate and accuracy of IP-Pealing reach 99.91% and 99.42%respectively.In comparison with the classical network flow watermarking methods,such as PROFW,IBW,ICBW,WBIPD and SBTT,the accuracy of IP-Pealing is increased by 13.70% to 54.00%.

关键词： Protocols Packet loss Watermarking Telecommunication traffic Jitter Robustness Internet