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中国空间科学学会空间物理学专业委员会第十五届全国日地空间物理学研讨会

作者： S.Y.Ma W.N.Yan L.Xu j.Goldstein d.j.mccomas dept.of Space Physics College of Electronic InformationWuhan University Southwest Research Institute 6220 Culebra RoadSan AntonioTX 78238-5166USA

The Two Wide-angle Imaging Neutral-atom Spectrometers(TWINS)mission of NASA is the first constellation to carry out stereoscopic magnetospheric imaging of energetic neutral atoms(ENA)from a twain of spacecrafts flying on two widely-separated Molniya *** provides unique opportunity to retrieve the 3-d distribution of ions in the ring currents(RC)by using volumetric pixel(voxel)CT inversion *** this study the voxel CT method is implemented for a series of differential ENA fluxes averaged over about 6 sweeps(corresponding to a time period of min.)at different energy levels ranging from 5 to 100 keV obtained during the main phase of a great magnetic storm with ***-H of-156 nT on October 24-25,*** data were selected to span a period about 50 minutes during which a large substorm was undergoing its expansion phase first and then *** ENA species of O and H are distinguished by analyzing the signals of pulse height of second electrons emitted from the carbon foil and impacted on the MCP detector in the TWINS *** eliminate the possible instrument bias error,a differential voxel CT technique is *** flux intensity of the ENAs’parent ions in the ring current(RC)has been obtained as a function of energy,L value,MLT sector and latitude,along with their time evolution during the storm-time substorm expansion *** shows that the RC is highly asymmetry with major part in the midnight to dawn sector for equatorial *** the midway of the substorm expansion there occurred a sudden large enhancement of equatorial ion flux at lower energy of 5 keV in the dusk sector with narrow extent less than 2 hours near the synchronous orbit of 5.5 *** ion flux spectra underwent dramatic *** the expansion maximum of the substorm,the spectra show a single peak at higher energy0 *** the midway of the expansion there are two peaks at higher and lowest energies,showing a valley at0 keV where the quiet time spectra have their peak and

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由TWINS星座ENA成像重建不同能量环电流离子的空间分布

由TWINS星座ENA成像重建不同能量环电流离子的空间分布

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第二十四届全国空间探测学术交流会

作者：马淑英颜伟男徐良 j.Goldstein d.j.mccomas 武汉大学电子信息学院空间物理系教育部《地球空间环境与大地测量》重点实验室 Southwest Research Institute 6220 Culebra RoadSan AntonioTX 78238-5166USA

考虑环电流能量离子通量随投掷角分布为各向异性,在偶极磁镜中运动时投掷角变化遵从磁矩不变原理,利用一次中等强度磁暴主相期间TWINS卫星星座不同能量段高能中性原子（ENA）成像数据,采用三维CT反演技术,重建了作为其生成源的环电流内... 详细信息

考虑环电流能量离子通量随投掷角分布为各向异性,在偶极磁镜中运动时投掷角变化遵从磁矩不变原理,利用一次中等强度磁暴主相期间TWINS卫星星座不同能量段高能中性原子（ENA）成像数据,采用三维CT反演技术,重建了作为其生成源的环电流内不同能量离子通量随磁纬和磁地方时的分布。在所考虑的时间段,TWINS的两颗卫星位于北极上空,距离地心5Re以远,在几乎相同的子午面内,但地方时相差约12小时。所用的ENA数据是成像仪对1-100keV内各个能量段内微分通量的12次扫描（相应时间长度16min）的累加平均。反演结果表明,环电流离子通量总体上主要位于L值大于4的区域,有随L增大而增强的趋势。环电流离子通量有两个最强的能段,一是最低的能量段1-2Kev,另一是30-100keV能段。两个能段环电流离子最大通量区域所在的磁地方时有明显差别,较低能量离子主要出现在子夜之后,而较高能量离子主要出现在子夜及之前。

关键词： ENA星座成像环电流 CT技术

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利用CT技术由TWINS星座ENA成像重建环电流离子分布

利用CT技术由TWINS星座ENA成像重建环电流离子分布

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第二十三届全国空间探测学术交流会

作者：马淑英颜伟男徐良 j.Goldstein d.j.mccomas 武汉大学电子信息学院 Southwest Research Institute 6220 Culebra RoadSan AntonioTX 78238-5166USA

美国NASA的TWINS是国际上第一个利用在两个交叉的莫尔尼亚轨道上的两颗卫星进行高能中性原子（ENA）广角成像的星座。地球空间中的能量离子与中性地冕氢冷原子之间发生电荷交换反应可以生成ENA。重建作为ENA生成源的离子的多维分布是解... 详细信息

美国NASA的TWINS是国际上第一个利用在两个交叉的莫尔尼亚轨道上的两颗卫星进行高能中性原子（ENA）广角成像的星座。地球空间中的能量离子与中性地冕氢冷原子之间发生电荷交换反应可以生成ENA。重建作为ENA生成源的离子的多维分布是解释卫星ENA成像数据的具有挑战性的一个难题。本文利用三维CT反演技术,由一次弱磁暴主相期间TWINS星座ENA成像数据,重建作为其生成源的环电流能量离子的空间分布。在所考虑的时间段,两颗卫星位于北极上空,距离地心5 RE以远,在几乎相同的子午面内但地方时相差约12个小时。在进行反演时,假定拟重建的能量离子通量不随投掷角而变,即为各向同性。所用的ENA数据是成像仪12次扫描（相应时间长度16 min）的累加平均,对1-100 keV所有能量的微分通量做累加。反演得到的ENA的离子源有两个分量:一是纬度较低而高度较高的环电流分量,另一是纬度较高而高度较低的极光/亚极光分量。总体来看,环电流分量的主要部分位于子夜至黎明扇区,L值约4至7或更远;亚极光分量主要出现在子夜前扇区。低高度的亚极光分量与dMSP卫星的能量离子当地测量比较一致。本文研究结果表明,利用类似TWINS这样的星座,在多个有利的空间位置进行全天空扫描来测量ENA,那么可以采用CT技术比较合理地重建得到环电流离子通量强度的三维空间分布。

关键词： ENA星座成像环电流 CT技术

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Kinetics of glyphosate and aminomethylphosphonic acid sorption onto montmorillonite clays in soil and their translocation to genetically modified corn

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journal of Environmental Sciences 2024年第1期135卷 669-680页

作者： Meichen Wang Kelly j Rivenbark Timothy d Phillips Veterinary Physiology and Pharmacology College of Veterinary Medicine and Biomedical SciencesTexas A&M UniversityTX 77845USA

The co-occurrence of glyphosate(GLP)and aminomethylphosphonic acid(AMPA)in contaminated water,soil,sediment and plants is a cause for concern due to potential threats to the ecosystem and human health.A major route of exposure is through contact with contaminated soil and consumption of crops containing GLP and AMPA ***,clay-based sorption strategies for mixtures of GLP and AMPA in soil,plants and garden produce have been very *** this study,in vitro soil and in vivo genetically modified corn models were used to establish the proof of concept that the inclusion of clay sorbents in contaminated soils will reduce the bioavailability of GLP and AMPA in soils and their adverse effects on plant *** of chemical concentration(1–10 mg/kg),sorbent dose(0.5%-3%in soil and 0.5%-1%in plants)and duration(up to 28 days)on sorption kinetics were *** time course results showed a continuous GLP degradation to *** inclusion of calcium montmorillonite(CM)and acid processed montmorillonite(APM)clays at all doses significantly and consistently reduced the bioavailability of both chemicals from soils to plant roots and leaves in a dose-and time-dependent manner without detectable *** treated with 0.5%and 1%APM inclusion showed the highest growth rate(p≤0.05)and lowest chemical bioavailability with up to 76%reduction in roots and57%reduction in *** indicated that montmorillonite clays could be added as soil supplements to reduce hazardous mixtures of GLP and AMPA in soils and plants.

关键词： Glyphosate AMPA Adsorption Soil remediation Plant Hydroponic system

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Generalized polynomial chaos expansion by reanalysis using static condensation based on substructuring

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Applied Mathematics and Mechanics(English Edition) 2024年第5期45卷 819-836页

作者： d.LEE S.CHANG j.LEE department of Automotive Engineering Hanyang UniversitySeoul 04763Republic of Korea School of Mechanical Engineering Chungnam National UniversityDaejeon 34134Republic of Korea department of Mechanical Robotics and Energy EngineeringDongguk UniversitySeoul 04620Republic of Korea

This paper presents a new computational method for forward uncertainty quantification(UQ)analyses on large-scale structural systems in the presence of arbitrary and dependent random *** method consists of a generalized polynomial chaos expansion(GPCE)for statistical moment and reliability analyses associated with the stochastic output and a static reanalysis method to generate the input-output data *** the reanalysis,we employ substructuring for a structure to isolate its local regions that vary due to random *** allows for avoiding repeated computations of invariant substructures while generating the input-output data *** substructuring with static condensation further improves the computational efficiency of the reanalysis without losing ***,the GPCE with the static reanalysis method can achieve significant computational saving,thus mitigating the curse of dimensionality to some degree for UQ under high-dimensional *** numerical results obtained from a simple structure indicate that the proposed method for UQ produces accurate solutions more efficiently than the GPCE using full finite element analyses(FEAs).We also demonstrate the efficiency and scalability of the proposed method by executing UQ for a large-scale wing-box structure under ten-dimensional(all-dependent)random inputs.

关键词： forward uncertainty quantification(UQ) generalized polynomial chaos expansion(GPCE) static reanalysis method static condensation substructuring

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Insm1:orchestrating cellular mimicry in the thymus medulla

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Cellular & Molecular Immunology 2024年第4期21卷 414-416页

作者： K.d.james j.E.Cowan UCL Institute of Immunity and Transplantation The Pears BuildingRowland Hill StreetLondonNW32PPUK

The thymus is the primary production site for a functional and self-tolerant T-cell *** establishment of immune tolerance is mediated by the generation and presentation of tissue-restricted self-antigens(TRAs)by medullary thymic epithelial cells(mTECs),which screen T-cell receptors for self-reactivity to eliminate autoreactive T *** studies have extended our understanding of mTEC heterogeneity by examining the mechanisms by which mTECs mimic the peripheral self[1].

关键词： medullary eliminate restricted

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Unmixing detrital zircon U-Pb ages reveals tectonic and climatic depositional influences on the Carboniferous Ansilta Formation,Calingasta-Uspallata Basin,Western Argentina

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Geoscience Frontiers 2024年第4期15卷 61-77页

作者： j.R.Malone j.E.Malone j.L.Isbell d.H.Malone j.P.Craddock K.N.Pauls department of Geological Sciences Jackson School of GeosciencesUniversity of Texas at AustinAustinTX 78712USA Iowa Geological Survey University of IowaIowa CityIA 52240USA department of Geosciences University of Wisconsin-MilwaukeeMilwaukeeWI 53211USA department of Geography Geology and the EnvironmentIllinois State UniversityNormalIL 61790-4400USA

The Late Paleozoic Ice Age(LPIA)was a principal control of sedimentation across Gondwana from the late devonian through early *** assess the hypothesis that glacial to interglacial transitions in western Argentina were the primary control influencing sediment routing patterns among the various Carboniferous-Permian basins in western *** Carboniferous Ansilta Formation consists of glaciomarine,nearshore,and fluvial systems deposited during the LPIA along the eastern margin of the Calingasta-Uspallata Basin in *** lower,glacially influenced succession of the Ansilta Formation records at least five glacial advances;the upper succession of consists of progradational shallow marine,deltaic,and fluvial *** combine 1225 new U-Pb zircon ages from six samples of the Carboniferous Ansilta Formation in the Calingasta-Uspallata Basin with 5864 U-Pb ages from 147 pub-lished samples in the detrital Pymix forward mixture model to characterize provenance *** the glacially influenced lower Ansilta Formation,sediment was derived locally from the Protoprecordillera,which was a prominent highland with alpine glaciers flowing west and east into the Calingasta-Uspallata and Paganzo basins,***,there was little or no connection between these two basins during Serpukhovian-Bashkirian *** fluvial/deltaic upper Ansilta had distal sediment sources in the Sierras ***,our results support the collapse of the Protoprecordillera topographic barrier,enabling drainage patterns connecting the Paganzo and Calingasta-Uspallata basins by late Pennsylvanian-early Permian time.

关键词： Late Paleozoic Ice Age Argentina Calingasta-Uspallata Basin Ansilta Formation detrital zircon provenance

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Mucopolysaccharidosis typeⅢB:a current review and exploration of the AAV therapy landscape

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Neural Regeneration Research 2024年第2期19卷 355-359页

作者： Courtney j.Rouse Victoria N.jensen Coy d.Heldermon Lacerta Therapeutics AlachuaFLUSA University of Florida College of Medicine GainesvilleFLUSA

Mucopolysaccharidoses typeⅢB is a rare genetic disorder caused by mutations in the gene that encodes for *** results in the aggregation of heparan sulfate polysaccharides within cell lysosomes that leads to progressive and severe debilitating neurological *** treatment options are expensive,limited,and presently there are no approved cures for mucopolysaccharidoses typeⅢ***-associated virus gene therapy has significantly advanced the field forward,allowing researchers to successfully design,enhance,and improve potential *** group recently published an effective treatment using a codon-optimized triple mutant adeno-associated virus 8 vector that restores N-acetyl-alpha-glucosaminidase levels,auditory function,and lifespan in the murine model for mucopolysaccharidoses typeⅢB to that seen in healthy ***,we review the current state of the field in relation to the capsid landscape,adeno-associated virus gene therapy and its successes and challenges in the clinic,and how novel adenoassociated virus capsid designs have evolved research in the mucopolysaccharidoses typeⅢB field.

关键词： adeno-associated virus central nervous system gene therapy heparan sulfate immune response mucopolysaccharidoses type IIIB N-acetyl-alpha-glucosaminidase newborn screening

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Generalized time-dependent generator coordinate method for induced fission dynamics

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Frontiers of physics 2024年第4期19卷 1-12页

作者： B.Li d.Vretenar T.Nikšić j.Zhao P.W.Zhao j.Meng State Key Laboratory of Nuclear Physics and Technology School of PhysicsPeking UniversityBeijing 100871China Physics department Faculty of ScienceUniversity of Zagreb10000 ZagrebCroatia Center for Circuits and Systems Peng Cheng LaboratoryShenzhen 518055China

The generalized time-dependent generator coordinate method(Td-GCM)is extended to include pairing *** correlated GCM nuclear wave function is expressed in terms of time-dependent generator states and weight *** particle–hole channel of the effective interaction is determined by a Hamiltonian derived from an energy density functional,while pairing is treated dynamically in the standard BCS approximation with time-dependent pairing tensor and single-particle occupation *** the inclusion of pairing correlations,various time-dependent phenomena in open-shell nuclei can be described more *** model is applied to the description of saddle-to-scission dynamics of induced *** generalized Td-GCM charge yields and total kinetic energy distribution for the fission of 240Pu,are compared to those obtained using the standard time-dependent density functional theory(Td-dFT)approach,and with available data.

关键词： nuclear density functional theory generator coordinate method fission dynamics

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Creep-induced redistribution of alloying elements in CZ1 zirconium alloys

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journal of Materials Science & Technology 2024年第6期173卷 31-44页

作者： W.T.Lin Q.Y.Lv d.jiao L.B.Zhang j.Tan G.Sha j.Hu China Nuclear Power Technology Research Institute Shenzhen 518026China School of Material Science and Engineering Nanjing University of Science and TechnologyNanjing 210094China

Introducing minor alloying elements is an effective strategy to improve the corrosion and mechanical properties of zirconium alloys for nuclear *** in-reactor service,external environment and stress can affect the distribution of alloying elements,substantially changing the degradation process of zirconium *** date,there is a lack of in-depth understanding of the interaction between creep and microchemistry ***,we conducted systematic transmission electron microscopy(TEM)and atom probe tomography(APT)investigations to address creep-induced redistribution of alloying elements in CZ1(Zr-Sn-Nb-Fe-Cr-Cu)zirconium alloy with different initial ***,Fe,Sn,and Cu are found to co-segregate at grain *** higher the intermediate annealing temperature,the larger the Gibbsian interfacial excesses of solute elements *** further demonstrate that creep can reduce the excess value of Fe at grain boundaries due to the coarsening of Zr-Fe-Cr second phase particles via grain boundary and dislocation pipe *** the same time,the excess value of Sn is increased by diffusing from the matrix to grain ***,Cu as a minor element in the concentration range of 0.05-0.3 wt.%is found to segregate at dislocations to form the Cottrell atmosphere and develop Cu-rich nanoclusters for suppressing dislocation *** new understanding of the segregation and clustering of minor alloying elements provides guidance for developing zirconium alloys with enhanced creep resistance.

关键词： Zirconium alloy Thermal creep Grain boundary segregation dislocation segregation Cu-rich nanoclusters

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