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Isolation and ex.ression analysis of anthocyanin biosynthetic genes in Morus alba l.

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Isolation and expression analysis of anthocyanin biosyntheti...

Seismogenic model of the 2023 MW5.5 Pingyuan earthquake in North China Plain and its tectonic implications

第十二届家（柞）蚕遗传育种暨良种繁育学术研讨会

作者： J.lI R.-H.lü A.-C.ZHAO x.-l.wang C.-Y.lIU Q.-Y.ZHANG x.-H.wang D.UMUHOZA x.-Y.JIN C.lU Z.-G.lI M.-D.YU College of Biotechnology Southwest University

Anthocyanins from mulberry fruits are used in medicine. However, little anthocyanin can be detected in other tissues and sometimes also mulberry fruits are colorless. The aim of this study was to investigate which gene or genes have the strongest correlation with the anthocyanin biosynthesis. The ex.ression of several anthocyanin synthesis genes were determined in different tissues of two white and two purple fruit cultivars. Genes encoding dihydroflavonol reductase（MaDFR） and anthocyanidin synthase（MaANS） showed a high ex.ression only in fruit tissue of purple-fruit *** the development of mulberry fruits, the anthocyanin content was well correlated with the transcripts abundance of MaDFR, MaANS, and MaCHS（encoding chalcone synthase）. The skin of female mulberry flowers turns red under irradiance because of up-regulated ex.ressions of MaCHS, MaDFR, and MaANS. These three genes may control the anthocyanin biosynthesis in mulberry and up-regulation of them may greatly increase the anthocyanin content. Additional key words: anthocyanidin synthase, chalcone isomerase, chalcone synthase, dihydroflavonol reductase, flavanone-3- hydrox.lase, phenylalanine ammonia lyase.

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Earthquake Science 2024年第6期37卷 499-513页

作者： wang S. Han l. x.e J. Fan l. Huang x. Bi J. Yang H. Fang l. Institute of Geophysics China Earthquake Administration Beijing 10081 China Tianjin Earthquake Agency Tianjin 300201 China Earth System Science Programme The Chinese University of Hong Kong Hong Kong Shatin 999077 China Beijing Baijiatuan Earth Science National Observation and Research Station Beijing 100095 China

The 6 August 2023 MW5.5 Pingyuan earthquake is the largest earthquake in the central North China Plain (NCP) over the past two decades. Due to the thick sedimentary cover, no corresponding active faults have been reported yet in the epicenter area. Thus, this earthquake presents a unique opportunity to delve into the buried active faults beneath the NCP. By integrating strong ground motion records, high-precision aftershock sequence relocation, and focal mechanism solutions, we gain insights into the seismotectonics of the Pingyuan earthquake. The aftershocks are clustered at depths ranging from 15 to 20 km and delineate a NE-SW trend, consistent with the distribution of ground motion records. A NE-SW nodal plane (226°) of the focal mechanism solutions is also derived from regional waveform inversion, suggesting that the mainshock was dominated by strike-slip motion with minor normal faulting component. Integrating regional geological data, we propose that an unrecognized fault between the NE-SW trending Gaotang and lingx.an-Yangx.n faults is the seismogenic fault of this event. Based on the S-wave velocity structure beneath the NCP, this fault probably ex.ends into the lower crust with a high angle. Considering the tectonic regime and stress state, we speculate that the interplay of shear strain between the Amurian and South China blocks and the hot upwelling magma from the subducted paleo Pacific flat slab significantly contributed to the generation of the Pingyuan earthquake. © 2024 The Authors

关键词： aftershock relocation focal mechanism North China Plain Pingyuan earthquake S-wave velocity structure

Ex.erimental Study on the Ax.al Compression Performance of Bamboo Scrimber Columns Embedded with Steel Reinforcing Bars

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SDHM Structural Durability and Health Monitoring 2024年第6期18卷 805-833页

作者： lin x. Wu M. li G. Guo N. Mei l. College of Civil Engineering and Transportation Northeast Forestry University Harbin 150000 China Department of Building Engineering College of Civil Engineering Tongji University Shanghai 200092 China College of Transportation and Civil Engineering Fujian Agriculture and Forestry University Fuzhou 350002 China

In this paper, a new type of bamboo scrimber column embedded with steel bars (rebars) was proposed, and the compression performance was improved by pre-embedding rebars during the preparation of the columns. The effects of the slenderness ratio and the reinforcement ratio on the ax.al compression performance of reinforced bamboo scrimber columns were studied by ax.al compression tests on 28 specimens. The results showed that the increase in the slenderness ratio had a significant negative effect on the ax.al compression performance of the columns. When the slenderness ratio increased from 19.63 to 51.96, the failure mode changed from strength failure to buckling failure, and the max.mum bearing capacity decreased by 43.03%. The ax.al compression performance of the reinforced bamboo scrimber columns did not significantly improve at a slenderness ratio of 19.63, but the opposite was true at slenderness ratios of 36.95 and 51.96. When the reinforcement ratio increased from 0% to 4.52%, the bearing capacity of those with a slenderness ratio of 51.96 increased by up to 16.99%, and the stiffness and ductility were also improved. Finally, based on ex.sting specifications, two modification parameters, the overall elastic modulus Ec and the combined strength fcc, were introduced to establish a calculation method for the bearing capacity of the reinforced bamboo scrimber columns. The calculation results were compared with the test results, and the results showed that the proposed calculation models can more accurately predict the bearing capacity. © 2024 The Authors.

关键词： ax.al compression performance Bamboo scrimber column steel bar theoretical model

Fast efficient photon deceleration in plasmas by using two laser pulses at different frequencies

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Matter and Radiation at Ex.remes 2024年第3期9卷 11-18页

作者： Y.x.wang x.l.Zhu S.M.Weng P.li x.F.li H.Ai H.R.Pan Z.M.Sheng Key laboratory for laser Plasmas(moe) School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China Collaborative Innovation Center of IFSA Shanghai Jiao Tong UniversityShanghai 200240China Research Center of laser Fusion of China Academy of Engineering Physics MianyangSichuan 621900China State key laboratory of High Field laser Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China Tsung-dao lee Institute Shanghai Jiao Tong UniversityShanghai 200240China

The generation of ultrashort high-power light sources in the mid-infrared(mid-IR)to terahertz(THz)range is of interest for applications in a number of fields,from fundamental research to biology and *** conventional laser technology,photon deceleration in plasma wakes provides an alternative approach to the generation of ultrashort mid-IR or THz ***,we present a photon deceleration scheme for the efficient generation of ultrashort mid-IR or THz pulses by using an intense driver laser pulse with a relatively short wavelength and a signal laser pulse with a relatively long *** signal pulse trails the driver pulse with an appropriate time delay such that it sits at the front of the second wake bubble that is driven by the driver *** to its relatively long wavelength,the signal pulse will be subjected to a large gradient of the refractive index.in the plasma wake ***,the photon deceleration in the plasma wake becomes faster and more efficient for signal pulses with longer *** greatly enhances the capacity and efficiency of photon deceleration in the generation of ultrashort high-power light sources in the long-wavelength IR and THz spectral ranges.

关键词： laser ultrashort photon

Precipitation of multi-type nano-quasicrystals in a Mg-Zn-Y alloy

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Journal of Magnesium and Alloys 2024年第3期12卷 997-1008页

作者： W.Z.wang x.Z.Zhou l.F.Zhang H.Q.Ye Z.Q.Yang Shenyang National laboratory for Materials Science Institute of Metal ResearchChinese Academy of ScienceShenyang 110016China Ji Hua laboratory Foshan 528251China Foshan University Foshan 528231China

Mg-6Zn-1Y(at.%)ribbons with strengthening precipitates of multi-type nanoquasicrystals were prepared by melt-spinning followed by aging *** evolution of the rapidly solidified ribbons during isothermal aging was comprehensively studied using various electron microscopy *** new kinds of decagonal quasicrystals were formed in aged ribbons,in addition to precipitation of nanometer icosahedral ***-resolution observations reveal that both decagonal quasicrystals can be modeled by quasiperiodic tiling with decagonal clusters of 2.5 nm in diameter,but overlap of neighboring clusters in both decagonal quasicrystals is different from the Gummelt model observed in other quasicrystals.A shell composed of complex.laves Mg-Zn domains was formed surrounding each decagonal quasicrystal precipitate upon prolonged *** addition,all kinds of nanoprecipitates ex.ibit ex.ellent structure and size stability at 573 *** findings may have implications for not only fundamental studies about quasicrystals,but also microstructural manipulation of high-performance Mg alloys.

关键词： Quasicrystal Mg alloys Rapid solidification Scanning-transmission electron microscopy.

Spalling characteristics of high-temperature treated granitic rock at different strain rates

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第4期16卷 1280-1288页

作者： l.F.Fan Q.H.Yang x.l.Du The Key laboratory of Urban Security and Disaster Engineering of Ministry of Education Beijing University of TechnologyBeijing100124China

The dynamic spalling characteristics of rock are important for stability analysis in rock *** paper presented an ex.erimental investigation on the dynamic spalling characteristics of granite with different temperatures and strain rates.A series of dynamic spalling tests with different impact velocities were conducted on thermally treated granite at different *** dynamic spalling strengths of granite with different temperatures and strain rates were determined.A model was proposed to correlate the dynamic spalling strength of granite,high temperature and strain *** results show that the spalling strength of granite decreases with increasing ***,the spalling strength of granite with a higher strain rate is larger than that with a lower strain *** proposed model can describe the relationship among dynamic spalling strength of granite,high temperature and strain rate.

关键词： Dynamic spalling characteristics High temperature Strain rate Dynamic loading Granite

In situ TEM investigation of electron irradiation and aging-induced high-density nanoprecipitates in an Mg-10Gd-3Y-1Zn-0.5Zr alloy

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Journal of Magnesium and Alloys 2024年第5期12卷 1841-1853页

作者： M.lv H.l.Ge Q.Q.Jin x.H.Shao Y.T.Zhou B.Zhang x.l.Ma Shenyang National laboratory for Materials Science Institute of Metal ResearchChinese Academy of Sciences72 Wenhua RoadShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Materials Science and Engineering Research Center Guangxi University of Science and TechnologyLiuzhou 545006China

In-situ electron irradiation and aging are applied to introduce high-density precipitates in an Mg-10Gd-3Y-1Zn-0.5Zr(GWZ1031K,wt.%)alloy to improve the *** results show that the hardness of the Mg alloy after irradiation for 10 h and aging for 9 h at 250℃ is 1.64 GPa,which is approx.mately 64% higher than that of the samples before being *** is mainly attributed to γ'precipitates on the basal plane after irradiation and the high-density nanoscale β'precipitates on the prismatic plane after aging,which should be closely related to the irradiation-induced homogenous *** latter plays a key role in precipitation *** result paves a way to improve the mechanical properties of metallic materials by tailoring the precipitation through irradiation and aging.

关键词： Mg alloy Electron beam irradiation Hardening Precipitates In-situ TEM

Electron kinetic effects in back-stimulated Raman scattering bursts driven by broadband laser pulses

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Matter and Radiation at Ex.remes 2024年第4期9卷 54-67页

作者： Q.K.liu l.Deng Q.wang x.Zhang F.Q.Meng Y.P.wang Y.Q.Gao H.B.Cai S.P.Zhu Graduate School China Academy of Engineering PhysicsBeijing 100088China Institute of Applied Physics and Computational Mathematics Beijing 100094China School of Nuclear Science and Technology University of Science and Technology of ChinaHefei 230026China Shanghai Institute of laser Plasma Shanghai 201800China HEDPS Center for Applied Physics and TechnologyPeking UniversityBeijing 100871China School of Physics Zhejiang UniversityHangzhou 310027China

We ex.mine electron kinetic effects in broadband-laser-driven back-stimulated Raman scattering(BSRS)bursts using particle-in-cell *** bursts occur during the nonlinear stage,causing reflectivity spikes and generating large numbers of hot ***-duration simulations are performed to observe burst events,and a simplified model is developed to eliminate the interference of the broadband laser’s random intensity *** the simplified model,we isolate and characterize the spectrum of electron plasma *** spectrum changes from a sideband structure to a turbulence-like structure during the burst.A significant asymmetry in the spectrum is *** asymmetry is amplified and transferred to electron phase space by high-intensity broadband laser pulses,leading to violent vortex.merging and generation of hot *** proportion of hot electrons increases from 6.76%to 14.7%during a single violent burst *** demonstrate that kinetic effects profoundly influence the BSRS evolution driven by broadband lasers.

关键词： scattering kinetic simplified

Comparison of Adaptive Simulation Observation Ex.eriments of the Heavy Rainfall in South China and Sichuan Basin

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Advances in Atmospheric Sciences 2024年第11期41卷 2173-2191页

作者： He l. Peng W. Zhang Y. Miao S. Chen S. li J. Shao D. Zhang x. College of Ocean and Meteorology Guangdong Ocean University Zhanjiang 524088 China Chinese Academy of Meteorology Sciences Beijing 100081 China Institute of Urban Meteorology China Meteorological Administration Beijing 100089 China School of Marine Sciences Nanjing University of Information Science and Technology Nanjing 210044 China Da1lian Marine Center Ministry of Nature Resources of the People’s Republic of China Dalian 116001 China

This study ex.mines the effectiveness of adaptive observation ex.eriments using the ensemble transformation sensitivity (ETS) method to improve precipitation forecasts during heavy rainfall events in South China and the Sichuan Basin. High-resolution numerical models are employed to simulate adaptive observations. By identifying the sensitive areas of key weather system positions 42 hours before heavy rainfall events, the adaptive observations improve the prediction of jet streams, strong winds, and shear lines, which are essential for accurate heavy rainfall forecasting. This improvement is reflected in both the precipitation structure and location accuracy within the verification region. In South China, targeted observations enhance rainfall predictions by improving water vapor transport. In the Sichuan Basin, adaptive observations refine water vapor transport and adjust vortex.dynamics. This research highlights the importance of accurately predicting shear lines and jet streams for forecasting heavy rainfall in these areas. Overall, this study found that adaptive observation enhances the precipitation forecast skills of the structure and location for heavy rainfall in South China and the Sichuan Basin, emphasizing their potential utility in operational numerical weather prediction. © Institute of Atmospheric Physics/Chinese Academy of Sciences, and Science Press 2024.

关键词： adaptive observation data assimilation ensemble transform sensitivity rainfall