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New Benthic Fossils from the Late Ediacaran Strata of Southwestern China

Acta Geologica Sinica(English Edition) 2024年第2期98卷 311-323页

作者： LIU Junping LI Ming TANG Feng ZHao Jiangtai song Sicun ZHOU Ying song Xiaohan REN Liudong School of Earth Science and Resources China University of GeosciencesBeijing 10083China Yunnan Institute of Geological Survey Kunming 650216China Chinese Academy of Geological Sciences Beijing 10037China Key Laboratory for Stratigraphy and Paleontology MNRCBeijing 10037China School of Earth Science and Engineering Nanjing UniversityNanjing 210093China Department of Earth Sciences University College LondonLondon WC1E 6BTU.K. CAS and Shandong Province Key Laboratory of Experimental Marine Biology Center for Ocean Mega-ScienceInstitute of OceanologyChinese Academy of SciencesQingdaoShandong 266071China Institute of Geology Chinese Academy of Geological SciencesBeijing 10037China

The Jiangchuan Biota from the Jiucheng Member(Mb.)of the Dengying Formation(Fm.),discovered in Jiangchuan,eastern Yunnan,China,is marked by copious macrofossils at the apex of the Ediacaran *** fauna features benthic algae with varied holdfasts and other fossils of indeterminate taxonomic affinity and is compositionally unique compared to the Shibantan and Gaojiashan biotas of the Dengying *** the Miaohe and Wenghui biotas of the Doushantuo Fm.,elsewhere in *** novel benthic saccular macroalgal fossil,named here Houjiashania yuxiensis *** ***.,from the Jiangchuan Biota is based on fossils that are sausage-shaped,elongate,tubular,ranging from 0.3 to 4 cm in length,and up to 0.8 cm in *** terminus is blunt and rounded to an obtuse angle,the other is bent with a spread-out surface resembling a holdfast,suggesting a three-dimensional ***,stipe-shaped outgrowths,likely vestiges of sessile saccular life forms,are prevalent in macroalgal fossils of analogous size and shape,as well as present brown algae Scytosiphonaceae,such as Colpomenia and *** new findings augment the diversity of benthic algae,such as those known from the Early Neoproterozoic Longfengshan Biota in North *** benthic algal macrofossils in the Jiucheng *** to knowledge of Late Ediacaran metaphyte diversification and offer more clues about the evolutionary positioning of primitive *** co-occurrence of numerous planktonic and benthic multicellular algae and planktonic microbes might have facilitated ecologically the more extensive later Cambrian explosion evidenced by the Chengjiang Biota in Yunnan.

关键词： paleophytology benthic saccular algae algal evolution Neoproterozoic Jiucheng Member Jiangchuan Biota Yunnan Province

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Modular synthesis of β-amino acids from alkenes,amines,and CO_(2) via photoredox/copper dual catalysis

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Science China Chemistry 2024年第6期67卷 1756-1757页

作者： Lei song Jie Wu Department of Chemistry National University of SingaporeSingapore117543Singapore National University of Singapore(Chongqing)Research Institute Chongqing401120China

The conversion of industrial waste into value-added chemicals represents a compelling approach to bolster sustainability *** the primary components of greenhouse gases,carbon dioxide(CO_(2))stands as an ideal C_(1) so... 详细信息

关键词： catalysis synthesis amines

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Toeplitz Operators and Carleson Measures for Weighted Bergman Spaces Induced by Regular Weights

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Acta Mathematica Sinica,English Series 2024年第5期40卷 1345-1359页

作者： Jun Tao DU song Xiao Hasi WULAN Department of Mathematics Guangdong University of Petrochemical TechnologyMaoming 525000P.R.China Department of Mathematics Shantou UniversityShantou 515063P.R.China

In this paper,we give a universal description of the boundedness and compactness of Toeplitz operator T_(μ)^(ω)between Bergman spaces A_(η)^(p)and A_(υ)^(q)whenμis a positive Borel measure,1 详细信息

In this paper,we give a universal description of the boundedness and compactness of Toeplitz operator T_(μ)^(ω)between Bergman spaces A_(η)^(p)and A_(υ)^(q)whenμis a positive Borel measure,1

关键词： Bergman space Carleson measure Toeplitz operator regular weight

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Improvement of Microstructure and Mechanical Properties of Rapid Cooling Friction Stir-welded A1050 Pure Aluminum

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Journal of Wuhan University of Technology(Materials Science) 2024年第1期39卷 134-141页

作者：许楠 LIU Lutao song Qining ZHao Jianhua Bao Yefeng College of Materials Science and Engineering Hohai UniversityChangzhou 213200China

Two-mm thick A1050 pure aluminum plates were successfully joined by conventional and rapid cooling friction stir welding(FSW), respectively. The microstructure and mechanical properties of the welded joints were investigated by electron backscatter diffraction characterization, Vickers hardness measurements, and tensile testing. The results showed that liquid CO_(2) coolant significantly reduced the peak temperature and increased the cooling rate, so the rapidly cooled FSW joint exhibited fine grains with a large number of dislocations. The grain refinement mechanism of the FSW A1050 pure aluminum joint was primarily attributed to the combined effects of continuous dynamic recrystallization, grain subdivision, and geometric dynamic recrystallization. Compared with conventional FSW, the yield strength, ultimate tensile strength, and fracture elongation of rapidly cooled FSW joint were significantly enhanced, and the welding efficiency was increased from 80% to 93%. The enhanced mechanical properties and improved synergy of strength and ductility were obtained due to the increased dislocation density and remarkable grain refinement. The wear of the tool can produce several WC particles retained in the joint, and the contribution of second phase strengthening to the enhanced strength should not be ignored.

关键词： aluminum alloy friction stir welding recrystallization microstructure mechanical properties

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CHIT1-positive microglia act as culprits for spinal motor neuron aging

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Science China(Life Sciences) 2024年第4期67卷 847-848页

作者： Zhao Wang Wantong Cai Weihong song Oujiang Laboratory(Zhejiang Lab for Regenerative Medicine Vision and Brain Health)Institute of AgingKey Laboratory of Alzheimer’s Disease of Zhejiang ProvinceThe Second Affiliated HospitalWenzhou Medical UniversityWenzhou 325035China

Aging is one of the primary factors in spinal cord-associated disorders(Roberts,1990).However,the effects of aging on the spinal cord and the age-specific mechanisms underlying this relationship remain *** neurons(MNs... 详细信息

关键词： aging Roberts positive

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Ship recognition based on HRRP via multi-scale sparse preserving method

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Journal of Systems Engineering and Electronics 2024年第3期35卷 599-608页

作者： YANG Xueling ZHANG Gong song Hu College of Electronic and Information Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China Key Lab of Radar Imaging and Microwave Photonics Ministry of EducationNanjing 210016China Nanjing Marine Radar Institute Nanjing 210016China

In order to extract the richer feature information of ship targets from sea clutter, and address the high dimensional data problem, a method termed as multi-scale fusion kernel sparse preserving projection(MSFKSPP) based on the maximum margin criterion(MMC) is proposed for recognizing the class of ship targets utilizing the high-resolution range profile(HRRP). Multi-scale fusion is introduced to capture the local and detailed information in small-scale features, and the global and contour information in large-scale features, offering help to extract the edge information from sea clutter and further improving the target recognition accuracy. The proposed method can maximally preserve the multi-scale fusion sparse of data and maximize the class separability in the reduced dimensionality by reproducing kernel Hilbert space. Experimental results on the measured radar data show that the proposed method can effectively extract the features of ship target from sea clutter, further reduce the feature dimensionality, and improve target recognition performance.

关键词： ship target recognition high-resolution range profile(HRRP) multi-scale fusion kernel sparse preserving projection(MSFKSPP) feature extraction dimensionality reduction

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Response characteristics of drill-string guided wave in downhole acoustic telemetry

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Chinese Physics B 2023年第3期32卷 299-307页

作者：赵傲耸陈浩何晓王秀明曹雪砷 State Key Laboratory of Acoustics Institute of AcousticsChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Beijing Engineering Research Center of Sea Deep Drilling and Exploration Institute of AcousticsChinese Academy of SciencesBeijing 100190China

Modeling of a drill-string acoustic channel has been an important topic in downhole telemetry for a long *** propagation of drill-string guided waves in the borehole contains excitation,attenuation,and mode conversion issues that have not been considered by existing modeling *** this article,we formulate a hybrid modeling method to investigate the response characteristics of a fundamental-mode drill-string wave in various borehole *** hybrid method provides channel functions,including transmitting and receiving deployments,periodicity of the structure,and formation property *** essential physics of the drill-string wave propagation is captured with a one-dimensional *** analytical solutions of the wavefield in multilayered cylindrical structures are introduced into a propagation matrix to express drill-string-wave interactions with the borehole *** effectiveness of the proposed method is confirmed through comparison with the finite-difference *** addition,by designing numerical models,we investigate the conversion effect of the drill-string wave at the tool *** demonstrate that the conversion intensity of the drill-string wave is positively correlated not only with the cross-sectional area of the tool joint but also with the wave impedance of the outer *** formation outside the borehole reduces the energy leakage while intensifying the conversion of drill-string waves to Stoneley waves,and the opposite is true for the drill string in an infinite *** converted Stoneley waves interfere with the drill-string waves,resulting in variations of bandgap distribution,which challenges the reliability of the data transmission.

关键词： downhole acoustic telemetry drill-string wave bandgap characteristic mode conversion

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A Novel Scalable Fault-Tolerant Control Design for DC Microgrids With Nonuniform Faults

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IEEE/CAA Journal of Automatica Sinica 2024年第8期11卷 1886-1888页

作者： Aimin Wang Minrui Fei Dajun Du Yang song the Shanghai Key Laboratory of Power Station Automation Technology the School of Mechatronic Engineering and Automation Shanghai University

Dear Editor,The existing control schemes for microgrids (MGs) face challenges in effectively addressing plugging in/out operations under uncertain power lines and faults. To tackle this issue, this letter proposes a novel scalable fault-tolerant control (FTC) strategy for DC MGs. By developing a structured Lyapunov matrix (SLM), a decoupled FTC method is introduced to mitigate the adverse effects of uncertain lines and nonuniform faults.

关键词： Linear matrix inequalities

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Integrative regulatory mechanisms of stomatal movements under changing climate

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Journal of Integrative Plant Biology 2024年第3期66卷 368-393页

作者： Jingbo Zhang Xuexue Chen Yajing song Zhizhong Gong State Key Laboratory of Nutrient Use and Management College of Resources and Environmental SciencesNational Academy of Agriculture Green DevelopmentChina Agricultural UniversityBeijing 100193China State Key Laboratory of Plant Cell and Chromosome Engineering Institute of Genetics and Developmental BiologyChinese Academy of SciencesBeijing 100101China State Key Laboratory of Plant Environmental Resilience College of Biological SciencesChina Agricultural UniversityBeijing 100094China Institute of Life Science and Green Development School of Life SciencesHebei UniversityBaoding 071001China

Global climate change-caused drought stress,high temperatures and other extreme weather profoundly impact plant growth and development,restricting sustainable crop *** cope with various environmental stimuli,plants can optimize the opening and closing of stomata to balance CO_(2)uptake for photosynthesis and water loss from *** cells perceive and integrate various signals to adjust stomatal pores through turgor pressure *** mechanisms and signaling networks underlying the stomatal movements in response to environmental stresses have been extensively studied and *** review focuses on the molecular mechanisms of stomatal movements mediated by abscisic acid,light,CO_(2),reactive oxygen species,pathogens,temperature,and other *** discussed the significance of elucidating the integrative mechanisms that regulate stomatal movements in helping design smart crops with enhanced water use efficiency and resilience in a climate-changing world.

关键词： environmental stress guard cell plant regulatory mechanisms stomatal movements

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Experimental clearance rate and intraguild predation of jellyfish Cyanea nozakii

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Journal of Oceanology and Limnology 2024年第1期42卷 128-140页

作者： Pengpeng WANG Fang ZHANG song SUN Shuguo LÜ CAS Key Laboratory of Marine Ecology and Environmental Sciences Institute of OceanologyChinese Academy of SciencesQingdao 266071China Laboratory for Marine Ecology and Environmental Sciences Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China University of Chinese Academy of Sciences Beijing 100049China Jiaozhou Bay Marine Ecosystem Research Station Chinese Academy of SciencesQingdao 266071China Center for Ocean Mega-Science Chinese Academy of SciencesQingdao 266071China Institute of Marine Ecology and Environment Hainan Academy of Environmental SciencesHaikou 570100China

Cyanea nozakii,a common jellyfish distributed in offshore China,has a complex trophic relationship with other zooplankton ***,few studies have reported the predation rates and prey selection patterns of *** medusae on different prey *** is also lacking on the intraguild predation of Aurelia coerulea(another common bloom jellyfish in offshore China)by *** address the knowledge gaps,the clearance rates of *** for different prey items,including copepods(small1000μm),fish larvae,and gelatinous prey(hydromedusae,*** ephyrae,and chaetognaths),were *** influence of predator size on the clearance rate was also ***,we examined the intraguild predation of *** on *** *** clearance rates of *** varied widely with prey organisms,being independent of prey *** organisms,except for chaetognaths,were captured with considerably high efficiency,followed by fish larvae and copepods,indicating the preferential prey selection of gelatinous organisms by *** clearance rate increased linearly with the cross-sectional area of *** size in medusae may,to some extents,underpin their capacity to capture more prey by increasing the encounter rate and capture success through *** preyed voraciously on *** in high feeding efficiency,but the clearance rate decreased with increasing ***(as prey)*** phenomenon of intraguild predation suggests a speculative hypothesis of potential population regulation of *** by *** information regarding the feeding ecology of *** reported in this study is important for understanding plankton dynamics in marine ecosystems with extensive occurrences of this jellyfish.

关键词： Scyphomedusae predation rate gelatinous organisms prey selection feeding mechanism

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