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THEMiS observations of two substorms on February 26,2008

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Science China(Technological Sciences) 2010年第5期53卷 1328-1337页

作者： CHU XiangNing PU ZuYin CAO Xin WANG Jue V.MiSHiN V.ANGELOPOULOS LiU Jiang WEi Yong K.H.GLASSMEiER J.MCFADDEN D.LARSON S.MENDE H.FREY C.T.RUSSELL i.mann D.SiBECK ZONG QiuGang FU SuiYan XiE Lun T.i.SAiFUDiNOVA M.V.TOLOCHKO L.A.SAPRONOVA H.REME E.LUCEK School of Earth and Space Sciences Peking UriiversityBeijing 100871China institute of Solar-Terrestrial Physics Russian Academy of Sciences iGPP UCLA instiute of Geophysics and Extraterrestrial Physics Technical University of BraunschweigBraunschweig and Max Planck Institute of Solar System Research Space Sciences Laboratory University of California Department of Physics University of Alberta Code 674 NASA/GSFC Centre d'Etude Spatiale des Rayonnements Blackett Laboratory Imperial College London

Two substorms occurred at ～04:05 and ～04:55 UT on February 26,2008 are studied with the in-situ observations of THEMiS satellites and ground-based aurora and magnetic field *** et *** made a comprehensive study of the 04:55 UT *** showed detailed features of the two substorms with much attention to the first event and to the rela-tionship between mid-tail magnetic reconnection(MR) and substorm *** was found that in the earlier stage of each substorm,a first auroral intensification occurred 2-3 min soon after the start of mid-tail MR,followed by a slow and very lim-ited *** auroral arcs were weak,short-lived,and localized,characterizing all features of a *** re-garded the first auroral brightening as the initial onset of the substorms.A few minutes later,a second stronger auroral intensification appeared,followed by quick and extensive *** was interesting to note that the second brightening and related poleward expansion happened almost simultaneously(within a couple of minutes) with the onset of earthward flow and dipolarization in the near-Earth tail and other phenomenon of the substorm expansion *** thus regarded the second auroral brightening as the major onset of the ***,it was seen that during the growth phase of the two substorms,the polar cap open flux Ψ kept increasing,while it quickly reduced during the substorm expansion and recovery *** variations of Ψ implied that the evolution of the two substorm expansion phases were closely related to MR of tail lobe open field *** of substorm activities revealed that the two events studied were small substorms;while estimate of MR rate indicated that the MR processes in the two substorms were *** aforementioned observations suggested that mid-tail MR initiated the pseudobreakup first;the earthward flow generated by MR transported magnetic flux and energy to the near-Earth tail to cause the formatio

关键词： substorm auroral intensification/brightening auroral expansion dipolarization magnetic reconnection

THEMiS星座对2008年2月26日磁层亚暴的观测--磁尾重联触发的亚暴分析研究

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中国科学：技术科学 2010年第5期40卷 565-574页

作者：褚项宁濮祖荫曹馨 V.MiSHiN 王珏魏勇宗秋刚傅绥燕谢伦 V.ANGELOPOULOS 刘江 K.H.GLASSMEiER J.MCFADDEN D.LARSON S.MENDE H.FREY C.T.RUSSELL i.mann D.SiBECK T.i.SAiFUDiNOVA M.V.TOLOCHKO L.A.SAPRONOVA H.REME E.LUCEK 北京大学地球与空间科学学院北京100871 institute of Solar-Terrestrial Physics Russian Academy of SciencesIrkutskRussia iGPP UCLALos AngelesCalifomiaUSA instiute of Geophysics and Extraterrestrial Physics Technical University of BraunschweigBraunschweig and Max Planck Institute of SolarSystem ResearchKatlenburg-LindauGermany Space Sciences Laboratory University of CaliforniaBerkeleyCaliforniaUSA Department of Physics University of AlbertaEdmontonAlbertaCanada Code 674 NASA/GSFCGreenbeltMDUSA Centre d'Etude Spatiale des Rayonnements ToulouseFrance Blackett Laboratory Imperial College LondonLondonUK

本文利用THEMiS卫星结合地面极光和地磁的观测,研究了2008年2月26日04:05和04:55UT的两次亚暴事件.Angelopoulos已经对发生在04:55UT的第二个亚暴事件做了分析.本文对两次亚暴的相关活动进行了详细研究,特别对第一次做了深入讨论,并着... 详细信息

本文利用THEMiS卫星结合地面极光和地磁的观测,研究了2008年2月26日04:05和04:55UT的两次亚暴事件.Angelopoulos已经对发生在04:55UT的第二个亚暴事件做了分析.本文对两次亚暴的相关活动进行了详细研究,特别对第一次做了深入讨论,并着重分析了磁重联与亚暴活动的关系.在两次亚暴的初始阶段,第一次极光增亮发生在中磁尾磁重联后2～3min,但是持续时间较短,极向膨胀缓慢,与伪暴的特征相似,标志了亚暴的初突发(initial onset).两次亚暴都存在第二次极光增亮和极光的极向膨胀,且时间与近地磁尾观测的地向流和磁场偶极化同时发生,并与亚暴膨胀相的其他活动的发生同步,标志了亚暴的主突发(major onset).在两次亚暴的增长相期间,极盖区开放磁通量持续增加;在亚暴膨胀相和恢复相中,极盖区磁通量迅速减少.表明两次亚暴膨胀相的演化分别与两次尾瓣开放磁力线重联过程相联系的.从亚暴活动的参数分析,这两次亚暴都属于小亚暴范围;从重联率分析,两次磁重联都属于弱重联.本文的观测结果表明,中磁尾磁尾重联首先触发伪暴;高速流将磁通量和能量传输到近地磁尾;高速流减速最终导致亚暴电流楔(substorm current wedge,简称SCW)的形成和电流中断,产生近地偶极化和极光膨胀,引起亚暴膨胀相突发.本文的观测结果是对近地中性线模型(near earth neutral line,简称NENL)和重联-电流中断协同模型(synthesis scenario of MR and CD,简称RCS)模型及亚暴膨胀相两步突发观点的有力支持.

关键词：亚暴极光增亮极光膨胀磁场偶极化磁重联

Arctic sea-ice extent: No record minimum in 2023 or recent years

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Atmospheric and Oceanic Science Letters 2025年第1期18卷 52-55页

作者： Ola M.Johannessen Tor i.Olaussen Nansen Scientific Society BergenNorway Nansen Environmental and Remote Sensing Center BergenNorway

Arctic sea-ice extent reaches its minimum each year in September. On 11 September 2023 the minimum was 4.969 million square kilometers(***^(2)). This was not a record low, which occurred in 2012, when the minimum was 4.175 ***^(2), 0.794 ***^(2) less than the minimum in 2023. However, the ice extent had decreased by 0.432 ***^(2) compared with 2022. Nevertheless, the summer melting in 2023 was remarkably less than expected when considering the strong heat waves in the atmosphere and ocean, with record temperatures set around the world. in general, there is a high correlation between the long-term decrease in sea-ice extent and the increasing CO_(2) in the atmosphere, where the increase of CO_(2) in recent decades explains about 80% of the decrease in sea ice in September, while the remainder is caused by natural variability.

关键词： Sea ice Arctic Minimum ice Climate

Coarse to Fine: The Role of Severe Plastic Deformation in Advancing Titanium-Based Medical implants - A Comprehensive Review

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 295-306页

作者： Dragana R Mihajlović Bojan i Međo ivana Lj Cvijović-Alagić Veljko R Djokić Faculty of Technology and Metallurgy University of BelgradeKarnegijeva 411120 BelgradeSerbia Vinča institute of Nuclear Sci-ences-National institute of the Republic of Serbia University of Belgrade11001BeogradSerbia innovation Centre of the Faculty of Technology and Metallurgy Karnegijeva 411120 BelgradeSerbia

This paper describes severe plastic deformation(SPD)procedures,which are utilized to form an ultrafine-grained structure in metallic *** the SPD process,a solid material sample is subjected to very high loads without a significant change in sample *** the present work,the high-pressure torsion(HPT)process,as one of the SPD techniques,which achieves a high degree of deformation and ensures refinement of the microstructure,will be discussed in more *** that grain size control is accepted as a method to obtain materials with desired characteristics,an overview of the properties of ultrafine-grained titanium-based biomaterials to be used in medicine is ***,particular attention is dedicated to the influences of HPT process parameters,primarily hydrostatic pressure,and number of revolutions during torsion,on the grain size and physical and mechanical characteristics(modulus of elasticity,microhardness,and tensile properties),corrosion resistance,and biocompatibility of the titanium-based biomaterials.A review of the literature indicates that titanium-based materials obtained by the SPD process show improved mechanical and physical properties without losing biocompatibility and corrosion resistance,which suggests that these methods of obtaining implants are something that should be further developed in the future.

关键词： high-pressure torsion process ultrafine-grained titanium-based materials electrochemical anodization physical properties mechanical properties

Multisensory mechanisms of gait and balance in Parkinson’s disease:an integrative review

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Neural Regeneration Research 2025年第1期20卷 82-92页

作者： Stiven Roytman Rebecca Paalanen Giulia Carli Uros Marusic Prabesh Kanel Teus van Laar Nico i.Bohnen Department of Radiology University of MichiganAnn ArborMIUSA Department of Neurology University of MichiganAnn ArborMIUSA Morris K.Udall Center of Excellence for Parkinson’s Disease Research University of MichiganAnn ArborMIUSA institute for Kinesiology Research Science and Research Centre KoperKoperSlovenia Department of Health Sciences Alma Mater Europaea–ECMMariborSlovenia Parkinson’s Foundation Research Center of Excellence University of MichiganAnn ArborMIUSA Department of Neurology University of GroningenUniversity Medical Center GroningenGroningenThe Netherlands Neurology Service and GRECC VA Ann Arbor Healthcare SystemAnn ArborMIUSA

Understanding the neural underpinning of human gait and balance is one of the most pertinent challenges for 21st-century translational neuroscience due to the profound impact that falls and mobility disturbances have on our aging *** and gait control does not happen automatically,as previously believed,but rather requires continuous involvement of central nervous *** effectively exert control over the body,the brain must integrate multiple streams of sensory information,including visual,vestibular,and somatosensory *** mechanisms which underpin the integration of these multisensory signals are the principal topic of the present *** multisensory integration theories focus on how failure of cognitive processes thought to be involved in multisensory integration leads to falls in older *** emphasis,however,has been placed on specific contributions of individual sensory modalities to multisensory integration processes and cross-modal interactions that occur between the sensory modalities in relation to gait and *** the present work,we review the contributions of somatosensory,visual,and vestibular modalities,along with their multisensory intersections to gait and balance in older adults and patients with Parkinson’s *** also review evidence of vestibular contributions to multisensory temporal binding windows,previously shown to be highly pertinent to fall risk in older ***,we relate multisensory vestibular mechanisms to potential neural substrates,both at the level of neurobiology(concerning positron emission tomography imaging)and at the level of electrophysiology(concerning electroencephalography).We hope that this integrative review,drawing influence across multiple subdisciplines of neuroscience,paves the way for novel research directions and therapeutic neuromodulatory approaches,to improve the lives of older adults and patients with neurodegenerative diseases.

关键词： aging balance encephalography functional magnetic resonance imaging gait multisensory integration Parkinson’s disease positron emission tomography somatosensory vestibular visual

Apolipoprotein A-i binding protein-mediated neuroprotection in glaucomatous neuroinflammation and neurodegeneration

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Neural Regeneration Research 2025年第5期20卷 1414-1415页

作者： Sinwoo Hwang Seunghwan Choi Soo-Ho Choi Keun-Young Kim Yury i.Miller Won-Kyu Ju Hamilton Glaucoma Center and Shiley Eye institute The Viterbi Family Department of OphthalmologyUniversity of California San DiegoLa JollaCAUSA Department of Medicine University of California San DiegoLa JollaCAUSA National Center for Microscopy and imaging Research Department of NeurosciencesUniversity of California San DiegoLa JollaCAUSA

Glaucoma is a multifactorial eye disorder that can cause vision loss and irreversible blindness,affecting individ uals aged 40 to 80 yea rs *** to the aging population,it is expected that the number of people affected by glaucoma will surpass 111 million by 2040 as the disease becomes more *** primarily contributes to optic nerve axon loss and the progressive degeneration of retinal ganglion cells (RGCs),subsequently leading to vision impairment.

关键词： irreversible pass primarily

Redescription of Cobitis longipectoralis Zhou, 1992 (Cypriniformes: Cobitidae) from late early Miocene of East China

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Science China Earth Sciences 2010年第7期53卷 945-955页

作者： CHANG Mee-mann Key Laboratory of Evolutionary Systematics of Vertebrates Institute of Vertebrate Paleontology and Palaeoanthropology Chinese Academy of Sciences

Here we revise a fossil cobitid species ■Cobitis longipectoralis Zhou, 1992, based mainly on a well-preserved specimen collected recently from the taxon’s type locality of the late early Miocene of Shanwang, Shandong Province, East China. The new specimen, along with those collected by Zhou, enables us to provide an emended diagnosis and more detailed description of the species by focusing on the characters such as the structures of the suborbital spine and the presence and shape of the lamina circularis at the base of the second pectoral fin ray in adult males, the presence of a frontoparietal fontanelle, and a quad- rate-metapterygoid fenestra, etc. The long pectoral fin, initially considered by Zhou as the most important character of the spe- cies, however, turns out to be not diagnostic for the species. ■Cobitis longipectoralis Zhou, 1992 is not only the most informative and best-preserved early cobitid fossil known thus far but also the only and earliest cobitid fossil from East Asia.

关键词： Cobitis longipectoralis late early Miocene East China

A new Eocene catostomid (Teleostei: Cypriniformes) from northeastern China and early divergence of Catostomidae

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Science China Earth Sciences 2009年第2期52卷 189-202页

作者： CHANG Mee-mann Key Laboratory of Evolutionary Systematics of Vertebrates Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences

A new Eocene catostomid genus and species,Plesiomyxocyprinus arratiae, is described from Huadian, Jilin Province, northeastern China. The materials include a nearly complete skeleton, dozens of pharyngeal bones with teeth, and a number of disarticulated bones. The new articulated specimen is large-sized and deep-bodied, with an estimated standard length of ca. 300 mm and body depth of 156 mm or about half of its standard length. The assignment of the fish to the Catostomidae is based on its falciform pharyngeal bone with one row of numerous (more than 50) compressed teeth, and the bone is much smaller than in cyprinids, especially given the size of the fish. The new fish distinguishes itself from all known catostomids (both extinct and extant) in its long anal fin with four unbranched and 17-18 branched rays, and its extremely short caudal peduncle that is only about one fourth of its depth. Plesiomyxocyprinus arratiae resembles the Eocene-Oligocene transpacific-distributed Amyzon in many general skeletal characters. However, it shows a few characters uniquely shared with the Recent catostomid Myxocyprinus asiaticus. Those include a very long dorsal fin with about 50 branched fin rays, the end of dorsal fin rays being close to the caudal fin base, and anal rays stretching posteriorly beyond the base of caudal fin. it is the first fossil catostomid that shows a close relationship to the endemic Myxocyprinus now living in the Yangtze River and Minjiang River, China. The discovery of Plesiomyxocyprinus arratiae, along with two previously described possible catostomid genera Jianghanichthys and Vasnetzovia, may indicate that the divergence of the Catostomidae started much earlier, in the middle Eocene or earlier, on the western side of the Pacific than on its eastern side.

关键词： a new catostomid genus Eocene northeastern China early divergence

Pliocene cyprinids (Cypriniformes,Teleostei) from Kunlun Pass Basin,northeastern Tibetan Plateau and their bearings on development of water system and uplift of the area

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Science China Earth Sciences 2010年第4期53卷 485-500页

作者： CHANG Mee-mann Key Laboratory of Evolutionary Systematics of Vertebrates Institute of Vertebrate Paleontology and PaleoanthropologyChinese Academy of Sciences

Here described are the cyprinid fossils from the Pliocene Lower Member of Qiangtang Formation of the Kunlun Pass Basin,northeastern Tibetan Plateau,collected at a locality 4769 m above the sea level(asl).The materials consist of numerous disarticulated and incomplete bones as well as thousands of pharyngeal teeth,fin rays,and *** fossils were referred to the genus Gymnocypris,lineage Schizothoracini,family Cyprinidae;the lineage Schizothoracini;and the family Cyprinidae *** Schizothoracini is a freshwater fish group endemic to the Tibetan Plateau and its surrounding *** workers on living schizothoracins regarded that Gymnocypris belongs to the highly specialized grade of the group,colonizing higher altitudes than other members of the *** species are so far unequivocally assigned to the genus,i.e.,*** and ***,and they are inhabiting Qinghai Lake and the waters on both north(the Golmud River) and south(upper reach of the Yellow River) sides of the East Kunlun Mountain,*** abundant fossil schizothoracins occur in the Kunlun Pass Basin on the southern slope of the East Kunlun Mountain(at 4769 m asl),close to the present Golmud River,indicating comparatively rich waters in the area and possible connections between the water systems on north and south sides of the East Kunlun Mountain during the *** also suggests a more humid climate in the area during the Pliocene than it is *** presence of the highly specialized schizothoracin Gymnocypris may also imply less amplitude of uplift(approximately 1000 m) in the area since the Pliocene than previously proposed.

关键词： Gymnocypris Schizothoracini Pliocene Kunlun Pass Basin of northeastern Tibetan Plateau development of water system uplift of the area