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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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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,1khinchin’s inequality and kahane’s inequality,we get a new characterization of the Carleson measure for Bergman spaces induced by regular weights.

关键词： Bergman space Carleson measure Toeplitz operator regular weight

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Narrative as“legal tender”:the semiotic meanings of“exchange”in Malcolm Bradbury’s Rates of Exchange

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Language and Semiotic Studies 2024年第3期10卷 343-366页

作者： Yanfang song School of Foreign Languages Soochow UniversitySuzhouChina

Malcolm Bradbury’s novel Rates of Exchange,taking the economic term“rates of exchange”as a central metaphor,depicts various exchanges occurring in the socio-economic landscape of Britain during the 1970s and *** the context of governmental emphasis on economic development,the novel intricately explores exchanges among diverse entities,playing with multiple meanings of the term“exchange”.In this way,the novel itself becomes a form of“legal tender,”exchanged for reader comprehension,communication,and *** highlights the ubiquitous presence of exchange and the risks associated with the uncertain exchange rates between different ***,it invites readers to participate in the story-telling and the nostalgic journey back to British literary *** paper,drawing on Roland Barthes’s semiotic theory along with structuralist and poststructuralist concepts,investigates the multifaceted meanings of“exchange”in the *** this analysis,the paper aims to illuminate the semiotic significance of various narrative forms and the profound thematic concerns in Bradbury’s work.

关键词： Rates of Exchange narrative Roland Barthes semiotics

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Mechanomedicine:From Mechanogenomics to Mechano-Immunoengineering

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医用生物力学 2024年第S1期 5-6页

作者： song Li Department of Bioengineering and Medicine University of California

Mechanobiology is a rapidly growing field that has expanded significantly over the past 40 years. There have been great examples of mechanobiology research on the cardiovascular, musculoskeletal, and respiratory systems. The field has evolved from the system level to the organ and tissue levels, and down to the cellular and molecular levels, benefiting from scientific progress and technological developments in molecular and cell biology, biomaterials, imaging techniques, and computational tools. Additionally, the interdisciplinary integration of mechanobiology with cell engineering, tissue engineering, and drug delivery has led to promising mechanomedicine applications in both therapeutics and ***, I will discuss two examples at the molecular and cellular levels:(1) mechanical regulation of epigenomics for cell reprogramming, and (2) engineering the mechanical properties of artificial antigen-presenting cells (APCs) for immune cell modulation and cancer *** memory of its identity is determined by the epigenetic state of the cells. However, how cells control the epigenetic state and thus cell fate is not well understood, and how mechanical factors such as surface topography, cell morphology,mechanical properties of the extracellular matrix (ECM), and the mechanical deformation of cells regulate the epigenetic state is not clear. In an early study, we showed that biophysical cues, in the form of parallel microgrooves on the surface of cell-adhesive substrates, can replace the effects of small-molecule epigenetic modifiers and significantly improve reprogramming efficiency from fibroblasts to induced pluripotent stem cells. The mechanism relies on the mechanomodulation of the cells’ epigenetic state through the activity of histone deacetylase and H3 methyltransferase. We also showed that microtopography promotes a mesenchymal-to-epithelial transition in adult fibroblasts. Nanofibrous scaffolds with aligned fiber orientation produce effects similar

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Combining TDLAS and multi-fusion algorithms for methane gas concentration detection

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Optoelectronics Letters 2024年第6期20卷 353-359页

作者： SHI Guojun song xinmin DONG Taiji School of Information&Electrical Engineering Heilongjiang Bayi Agricultural UniversityDaqing 163319China College of Electrical and Information Engineering Northeast Petroleum UniversityDaqing 163318China

High-precision methane gas detection is of great importance in industrial safety, energy production and environmental protection, etc. However, in the existing measurement techniques, the methane gas concentration information is susceptible to noise, which leads to its useful signal being drowned by noise. A fusion algorithm of variational modal decomposition(VMD) and improved wavelet threshold filtering is proposed, which is used in combination with tunable diode laser absorption spectroscopy(TDLAS) to implement a non-contact, high-resolution methane gas concentration detection. The fusion algorithm can perform noise reduction and further segmentation of the methane gas detection signal. And the simulation and experiment verify the effectiveness of the fusion algorithm, and the experimental results show that for the detection of air containing 10 ppm, 30 ppm, 60 ppm, 80 ppm, and 99 ppm methane, the errors are 12.75%, 8.18%, 3.37%, 2.46%, and 1.78%, respectively.

关键词： Combining TDLAS and multi-fusion algorithms for methane gas concentration detection TDLAS

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Personal data security and stock crash risk:Evidence from China’s Cybersecurity Law

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China Journal of Accounting Research 2024年第4期17卷 1-23页

作者： Ziwei song Tsinghua University School of Economics and ManagementChina

Using China’s Cybersecurity Law(CSL)as an exogenous shock,I examine how personal data security affects stock crash risk.I find that the stock crash risk of treatment firms(which collect personal data)significantly decreases after the CSL,and such decrease is larger when firms face greater personal data breach risk and have less transparent information environments before the ***,treatment firms increase their investment in personal data protection after the ***,enhanced personal data security increases firm value and promotes firms’social responsibility to ***,I provide evidence of the importance of data security for the digital economy from the perspective of capital market stability,which may present implica-tions for data security policy worldwide.

关键词： Personal Data Data Security Stock Crash Risk Cybersecurity Law

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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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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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Receptivity of Mack modes to localized unsteady blowing and suction in a chemical non-equilibrium hypersonic boundary layer

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Acta Mechanica Sinica 2024年第7期40卷 1-18页

作者： Qingjiang Yuan Runjie song Ming Dong State key laboratory of Nonlinear Mechanics Institute of MechanicsChinese Academy of SciencesBeijing 100190China

This paper studies the local receptivity of the Mack-mode instability to localized unsteady blowing and suction(UBS)in a chem-ical non-equilibrium(CNE)hypersonic boundary *** five-species CNE model is employed,and the receptivity efficiency is formulated by use of the residual *** with the results for the calorically perfect gas(CPG)model,we find that the real-gas effect enhances the receptivity efficiency remarkably in the majority of the second-mode frequency band,and the enhancement is mainly attributed to the modification of the base flow due to the CNE effect,which is akin to the cold-wall effect in hypersonic boundary *** with the destabilizing role of the CNE effect on the Mack second mode,it is concluded that the CNE effect would lead to a greater linearly accumulated perturbation amplitude,implying premature of transition to turbulence in a high-enthalpy hypersonic boundary layer subject to localized perturbations.

关键词： Chemical non-equilibrium flow Boundary-layer instability Hypersonic Receptivity Transition to turbulence

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