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Recent advances in the magnetic reconnection, dipolarization, and auroral processes at giant planets from the perspective of comparative planetology

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Earth and Planetary Physics 2024年第5期8卷 659-672页

作者： ZhongHua Yao ruilong guo Yong Wei Bertrand Bonfond Denis Grodent BinZheng Zhang William R.Dunn ZuYin Pu Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of Sciences College of Earth and Planetary Sciences University of Chinese Academy of Sciences Laboratoire de Physique Atmosphérique et Planétaire STAR InstituteUniversitéde Liège Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment Institute of Space SciencesShandong University Department of Earth Sciences the University of Hong Kong Department of Physics and Astronomy University College London School of Earth and Space Sciences Peking University

Magnetic reconnection and dipolarization are crucial processes driving magnetospheric dynamics, including particle energization, mass circulation, and auroral processes, among others. Recent studies have revealed that these processes at Saturn and Jupiter are fundamentally different from the ones at Earth. The reconnection and dipolarization processes are far more important than previously expected in the dayside magnetodisc of Saturn and potentially Jupiter. Dayside magnetodisc reconnection was directly identified by using Cassini measurements(guo RL et al., 2018b) and was found to be drizzle-like and rotating in the magnetosphere of Saturn(Delamere et al., 2015b; Yao ZH et al., 2017a; guo RL et al., 2019). Moreover, magnetic dipolarization could also exist at Saturn's dayside(Yao ZH et al., 2018), which is fundamentally different from the terrestrial situation. These new results significantly improve our understanding of giant planetary magnetospheric dynamics and provide key insights revealing the physics of planetary aurorae. Here, we briefly review these recent advances and their potential implications for future investigations.

关键词： magnetosphere magnetic reconnection magnetic depolarization

Dynamic kinetic stereodivergent transformations of propargylic ammonium salts via dual nickel and copper catalysis

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Chinese Chemical Letters 2024年第8期35卷 265-269页

作者： ruilong Geng Lingzi Peng Chang guo Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemistry University of Science and Technology of ChinaHefei 230026China

The dynamic kinetic asymmetric transformation of racemic propargylic ammonium salts with prochiral aldimine esters through a stereodivergent propargylation is catalyzed by dual nickel and copper ***,a diverse range of optically activeα-quaternary amino esters were produced via C-N bond cleavage with high reaction efficiency and stereoselectivity(up to>99%ee).By selection of the appropriate pair-wise combination of catalyst configurational isomers,all four possible stereoisomers of the corresponding propargylation products are obtained in high yields with excellent regio-,diastereo-,and enantioselectiv-ities.

关键词： Stereodivergent propargylation Dual catalysis C-N bond cleavage Azaomethine ylides Internal propargylic ammonium salts Excellent stereoselectivity

Anomalous magnetic property and broadband photodetection in ultrathin non-layered manganese selenide semiconductor

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Nano Research 2024年第9期17卷 8578-8584页

作者： Ye Zhao ruilong Yang Ke Yang Jiarui Dou Xiaoting Yang Jinzhong guo guowei Zhou Xiaohong Xu School of Chemistry and Materials Science Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of EducationShanxi Normal UniversityTaiyuan 030006China Research Institute of Materials Science Collaborative Innovation Center for Shanxi Advanced Permanent Magnetic Materials and TechonologyShanxi Normal UniversityTaiyuan 030006China

Two-dimensional(2D)semiconductors with intrinsic ferromagnetism are highly desirable for potential applications in nextgeneration spintronic and optoelectronic ***,controllable synthesis of intrinsic 2D magnetic semiconductor on a substrate is still a challenging ***,large-area 2D non-layered rock salt(α-phase)MnSe nanosheets were grown on mica substrates,with the thickness changing from 54.2 to 0.9 nm(one unit cell),by chemical vapour *** X-ray diffraction,Raman spectroscopy,transmission electron microscopy,and X-ray photoelectron spectroscopy measurements confirmed that the resulting 2Dα-MnSe nanosheets were obtained as high-quality single *** magnetic hysteresis loops and synchrotron X-ray measurements directly indicated the anomalous magnetic properties inα-MnSe *** analysis of the reasons for magnetic property revealed that the low-temperature phase transition,small number of stacking differences in crystals,and surface weak oxidation in(111)-orientedα-MnSe were the main ***,α-MnSe nanosheets exhibited broadband photoresponse from 457 to 671 nm with an outstanding detectivity and responsivity *** study presents the detailed growth process of ultrathin 2D magnetic semiconductorα-MnSe,and its outstanding magnetic properties and broadband photodetection,which provide an excellent platform for magneto-optical and magneto-optoelectronic research.

关键词： two-dimensional material anomalous magnetism broadband photodetection α-phase MnSe non-layered crystal

Sawtooth and dune auroras simultaneously driven by waves around the plasmapause

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Earth and Planetary Physics 2023年第2期7卷 237-246页

作者： Fei He ZhongHua Yao BinBin Ni Xing Cao ShengYi Ye ruilong guo JinXing Li ZhiPeng Ren XinAn Yue YongLiang Zhang Yong Wei XiaoXin Zhang ZuYin Pu Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Department of Space Physics School of Electronic InformationWuhan UniversityWuhan 430072China Department of Earth and Space Sciences Southern University of Science and TechnologyShenzhen 518055China Institute of Space Sciences Shandong UniversityWeihai Shandong 264209China Department of Atmospheric and Oceanic Sciences University of CaliforniaLos AngelesCaliforniaUSA Johns Hopkins University Applied Physics Laboratory LaurelMaryland 20723USA Key Laboratory of Space Weather National Center for Space WeatherChina Meteorological AdministrationBeijing 100081China Institute of Space Physics and Applied Technology Peking UniversityBeijing 100871China

The dune aurora,at a scale of~30 kilometers,was reported recently using ground *** small-scale dune aurora occurs on the duskside and exhibits a monochromatic oscillation in the auroral emission,implying fundamental energy ***,whether the dune auroras correspond to atmospheric waves or are associated with magnetospheric dynamics should be *** paper reports a dune aurora that occurred during a storm;further,we demonstrate that it was the substructure of the sawtooth aurora that was generated by plasmapause surface *** observations in the magnetospheric source region suggest that the exohiss waves,which are periodically modulated by the plasmapause surface wave-excited ultralow frequency wave,might be responsible for the generation of the dune *** reported dune aurora events have occurred simultaneously with sawtooth auroras,suggesting that both are plasmapause-driven cross-scale auroral structures.

关键词： sawtooth aurora dune aurora plasmapause surface wave exohiss

Propagation properties of foreshock cavitons: Cluster observations

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Science China(Technological Sciences) 2020年第1期63卷 173-182页

作者： WANG MengMeng YAO ShuTao SHI QuanQi ZHANG Hui TIAN AnMin DEGELING Alexander William ZHANG Shuai guo ruilong SUN WeiJie LIU Ji BAI ShiChen SHEN XiaoChen ZHU XiaoQiong FU SuiYan PU ZuYin School of Space Science and Physics Shandong UniversityWeihai 264209China National Space Science Center Chinese Academy of SciencesBeijing 100190China Geophysical Institute University of Alaska FairbanksFairbanksAlaska 99775USA Institute of Geology and Geophysics Chinese Academy of SciencesBeijing 100029China Department of Climate and Space Sciences and Engineering University of MichiganAnn Arbor 48113USA Institute of Space Physics and Applied Technology Peking UniversityBeijing 100871China

Foreshock cavitons are transient phenomena observed in the terrestrial foreshock *** are characterized by a simultaneous depression of magnetic field magnitude and plasma density,which are bounded with enhancements of these two parameters and surrounded by ultralow frequency(ULF)*** studies focused on the interplanetary magnetic field(IMF)conditions,solar wind(SW)conditions,and the growth of the foreshock waves related to the generation of foreshock ***,a multipoint spacecraft analysis method using Cluster data was applied to analyze only two foreshock cavitons,and this method did not consider *** this study,multipoint spacecraft analysis methods,including the timing method,the minimum directional derivative(MDD)method,and the spatiotemporal difference(STD)method are applied to determine the velocity in both spacecraft and solar wind *** propagation properties show good agreement with previous results from simulations and observations that most cavitons move sunward in the solar wind frame,with the velocities larger than the Alfvén *** propagation properties of foreshock cavitons support the formation mechanism of cavitons in previous simulations,which suggested that cavitons are formed due to the nonlinear evolution of compressive ULF *** find that there is clear decreasing trend between the size of cavitons and their velocity in the solar wind *** addition,the timing method considering errors has been applied to study the evolution properties by comparing the velocities with errors of the leading and trailing edges,and we identify three stable cavitons and one contracting caviton,which has not been studied *** cavitons should remain stable when they travel toward the Earth’s bow *** relationship between the size of foreshock cavitons and their distance from the bow shock is also discussed.

关键词： foreshock transient phenomena cavitons nonlinear evolution of ULF waves propagation and evolution properties of structures multipoint spacecraft methods

Evolution of clustered magnetic nulls in a turbulent-like reconnection region in the magnetotail

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Science Bulletin 2016年第24期61卷 1145-1150页

作者： ruilong guo Zuyin Pu Suiyan Fu Lun Xie Malcolm Dunlop Yulia V. Bogdanova Jiansen He Xin Wang Zhonghua Yao School of Earth and Space Sciences Peking UniversityBeijing 100871 China PKU/UCLA Joint Research Institute in Science and Engineering Peking University Beijing 100871 China School of Astronautics Beihang University Beijing 100191China RAL Space Rutherford Appleton Laboratory STFCDidcot OXll 0QX UK UCL Mullard Space Science Laboratory Dorking RH5 6NT UK

t Magnetic null points and flux ropes play important roles in the three-dimensional process of magnetic reconnection. In this study, a cluster of null points are reconstructed in the reconnection region in the magnetotail by applying a fitting-reconstruction method to measurements from the Cluster mission. The number of recon- structed null points varies rapidly, presenting a turbulentlike evolution of the magnetic structure. The electron density and the flux of the accelerated electrons were enhanced in this turbulent-like region. During this unstable reconnection process, a B-As-B null structure was formed, showing flux rope features and resembling a secondary island in the observation.

关键词： Magnetic reconnection - Turbulent Magnetic null point Flux ropes Magnetotail

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Statistical properties of kinetic-scale magnetic holes in terrestrial space

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Earth and Planetary Physics 2021年第1期5卷 63-72页

作者： ShuTao Yao ZongShun Yue QuanQi Shi Alexander William Degeling HuiShan Fu AnMin Tian Hui Zhang Andrew Vu ruilong guo ZhongHua Yao Ji Liu Qiu-Gang Zong XuZhi Zhou JingHuan Li WenYa Li HongQiao Hu YangYang Liu WeiJie Sun Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment Institute of Space SciencesShandong UniversityWeihai Shandong 264209China State Key Laboratory of Space Weather National Space Science CenterChinese Academy of SciencesBeijing 100190China School of Space and Environment Beihang UniversityBeijing 100191China Physics Department and Geophysical Institute University of Alaska FairbanksFairbanksAK99775USA Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Laboratoire de Physique Atmosphérique et Planétaire STAR InstituteUniversitéde LiègeLiègeB-4000Belgium School of Earth and Space Sciences Peking UniversityBeijing 100871China SOA Key Laboratory for Polar Science Polar Research Institute of ChinaShanghai 200136China Department of Climate and Space Sciences and Engineering University of MichiganAnn ArborMI48109USA

Kinetic-scale magnetic holes(KSMHs)are structures characterized by a significant magnetic depression with a length scale on the order of the proton *** structures have been investigated in recent studies in near-Earth space,and found to be closely related to energy conversion and particle acceleration,wave-particle interactions,magnetic reconnection,and turbulence at the ***,there are still several major issues of the KSMHs that need further study—including(a)the source of these structures(locally generated in near-Earth space,or carried by the solar wind),(b)the environmental conditions leading to their generation,and(c)their spatio-temporal *** this study,KSMHs in near-Earth space are investigated statistically using data from the Magnetospheric Multiscale *** 200,000 events were observed from September 2015 to March *** rates of such structures in the solar wind,magnetosheath,and magnetotail were *** find that KSMHs occur in the magnetosheath at rates far above their occurrence in the solar *** indicates that most of the structures are generated locally in the magnetosheath,rather than advected with the solar ***,KSMHs occur in the downstream region of the quasi-parallel shock at rates significantly higher than in the downstream region of the quasi-perpendicular shock,indicating a relationship with the turbulent plasma *** to the magnetopause,we find that the depths of KSMHs decrease as their temporal-scale *** also find that the spatial-scales of the KSMHs near the subsolar magnetosheath are smaller than those in the ***,their global distribution shows a significant dawn-dusk asymmetry(duskside dominating)in the magnetotail.

关键词： kinetic scale magnetic hole magnetic dip electron vortex turbulence

miR-125b reverses cisplatin resistance by regulating autophagy via targeting RORA/BNIP3L axis in lung adenocarcinoma

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Oncology Research 2024年第4期32卷 643-658页

作者： LEI LIU NA guo XIANGLING LI QIAN XU ruilong HE LIMIN CHENG CHUNYAN DANG XINYU BAI YIYING BAI XIN WANG QIANHUI CHEN LI ZHANG Department of Immunology Chengde Medical UniversityChengde067000China Department of Pathology Chengde Medical UniversityChengde067000China Department of Oncology The Affiliated Hospital of Chengde Medical UniversityChengde067000China Department of Hepatobiliary Surgery The Affiliated Hospital of Chengde Medical UniversityChengde067000China

The platinum-based chemotherapy is one of the most frequently used treatment protocols for lung adenocarcinoma(LUAD),and chemoresistance,however,usually results in treatment failure and limits its application in the *** has been shown that microRNAs(miRNAs)play a significant role in tumor *** this study,miR-125b was identified as a specific cisplatin(DDP)-resistant gene in LUAD,as indicated by the bioinformatics analysis and the real-time quantitative PCR *** decreased serum level of miR-125b in LUAD patients was correlated with the poor treatment response rate and short survival ***-125b decreased the A549/DDP proliferation,and the multiple drug resistance-and autophagy-related protein expression levels,which were all reversed by the inhibition of *** addition,xenografts of human tumors in nude mice were suppressed by miR-125b,demonstrating that through autophagy regulation,miR-125b could reverse the DDP resistance in LUAD cells,both in vitro and in *** mechanistic studies indicated that miR-125b directly repressed the expression levels of RORA and its downstream BNIP3L,which in turn inhibited autophagy and reversed *** on these findings,miR-125b in combination with DDP might be an effective treatment option to overcome DDP resistance in LUAD.

关键词： Lung adenocarcinoma miRNAs Cisplatin Resistance Autophagy

不同日粮组成对围产期奶牛泌乳性能和乳品质的影响

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养殖与饲料 2023年第8期22卷 9-12页

作者：郭瑞龙山东省费县农业农村局农业技术推广中心山东费县273400

[目的]研究不同日粮组成对围产期奶牛泌乳性能和乳品质的影响,确定适合围产期奶牛的适宜精粗比日粮组成,为提高围产期奶牛生产性能和养殖经济效益提供依据。[方法]将30头围产前期荷斯坦奶牛随机分为3组(A、B、C组),每组10头,A、B、C组... 详细信息

[目的]研究不同日粮组成对围产期奶牛泌乳性能和乳品质的影响,确定适合围产期奶牛的适宜精粗比日粮组成,为提高围产期奶牛生产性能和养殖经济效益提供依据。[方法]将30头围产前期荷斯坦奶牛随机分为3组(A、B、C组),每组10头,A、B、C组饲喂精饲料与粗饲料比列分别为40∶60、50∶50、60∶40的全混合日粮,测定平均日采食量、平均日产奶量、料奶比等泌乳性能检测指标和乳脂率、乳蛋白率、乳糖率、体细胞数等乳品质检测指标。[结果]B组与A组相比,平均日采食量、平均日产奶量、乳蛋白率均显著提高,牛奶体细胞数显著降低;C组与A组相比,平均日采食量、平均日产奶量、乳脂率、乳蛋白率、乳糖率均显著提高,料奶比、牛奶体细胞数均显著降低;C组与B组相比,平均日产奶量、乳蛋白率均显著提高,牛奶体细胞数显著降低。[结论]随着围产期奶牛日粮中精饲料所占比例的逐步提高,围产期奶牛的泌乳性能和乳品质逐渐提高。

关键词：日粮组成围产期奶牛泌乳性能乳品质

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