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Near Earth Vortices Driving of Field Aligned currents Based on Magnetosphere Multiscale and Swarm Observations

空间科学学报 2019年第1期39卷 9-17页

作者： ZHANG c SHEN c YANG Y Y DUNLOP M W tI S russell c t LüHR H BURcH J L LINDQVISt P A tORBERt R B FRIIS-cHRIStENSEN E State Key Laboratory of Space Weather National Space Science Center college of Earth Science University of Chinese Academy of Sciences college of Science Harbin Institute of Technology Institute of china Seismological Bureau Crustal Stress Space Science Institute School of Astronautics Beihang University Rutherford Appleton Laboratory University of california German Research center For Geosciences German Research Center for Geosciences Southwest Research Institute Royal Institute of technology University of New Hampshire Danish National Space center

A long-standing mystery in the study of Field-Aligned currents(FAcs) has been that: how the currents are generated and why they appear to be much stronger at high altitudes than in the ionosphere. Here we present two events of magnetotail FAcs observed by the Magnetospheric Multiscale Spacecraft(MMS) on 1 st July and 14 th July 2016, to show how the Substorm current Wedges(ScW) were formed. the results show that particles were transferred heading towards the Earth during the expansion phase of *** azimuthal flow formed clockwise(counter-clockwise) vortex-like motion, and then generated downward(upward) FAcs on the tailward/poleward side of the distorted field with opposite vorticity on their Earthward/equatorward side. We also analyzed the Region 1 FAcs observed by the Earth Explorer Swarm spacecraft on 1 st July 2016 and found that they were associated with FAcs observed by MMS, although differing by a factor of 10. this difference suggests that either there was the closure of the currents at altitudes above 500 km or the currents were not strictly parallel to B and closed at longitudes away from where they were generated.

关键词： Substorm current wedge Magnetosphere Field-aligned currents Flow vorticity Multiple spacecraft measurements

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Large-Scale Parallel Electric Field colocated in an Extended Electron Diffusion Region During the Magnetosheath Magnetic Reconnection

Large-Scale Parallel Electric Field Colocated in an Extended...

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2022年中国地球科学联合学术年会

作者： Wang Shimou Wang Rongsheng Lu Quanming russell c.t. Ergun R.E. Wang Shui University of Science and technology of china University of california Los Angeles University of colorado

In this letter, we report observations from the Magnetospheric Multiscale (MMS) mission of large-scale parallel electric fields in a magnetosheath reconnecting current sheet. the four MMS satellites successively crossed an electron jet embedded in a broad current sheet, and detected a unipolar parallel electric field being co-located with the jet.

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MMS星座对磁层顶磁通量绳内离子惯性尺度结构的观测

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空间科学学报 2018年第2期38卷 147-168页

作者：刘杨濮祖荫谢伦郭瑞龙王晓钢肖池阶史全岐 DUNLOP M BOGDANOVA Y V MOORE t E russell c t LINDQVISt P A tORBERt R B POLLOcK c ZHAO cong 北京大学地球与空间科学学院北京100871 中国科学院地质与地球物理研究所北京100029 哈尔滨工业大学物理系哈尔滨150001 北京大学物理学院北京100871 山东大学空间科学与物理学院威海264209 RAL Space Rutherford Appleton LaboratorySTFCDidcotOX11 0QXUK Goddard Space Flight center NASAGreenbeltMDUSA University of california Los AngelesCAUSA Royal Institute of technology StockholmSweden University of New Hampshire DurhamNHUSA

利用MMS观测数据,对磁层顶通量绳内离子惯性尺度(d_i)的结构进行分析研究.结果发现,许多不同尺度(约1d_i至数十d_i)的通量绳内都存在具有d_i尺度的电流j_m,其方向在磁层顶局地坐标系的-M方向,即与磁层顶查普曼-费拉罗电流同向,由电子在+... 详细信息

利用MMS观测数据,对磁层顶通量绳内离子惯性尺度(d_i)的结构进行分析研究.结果发现,许多不同尺度(约1d_i至数十d_i)的通量绳内都存在具有d_i尺度的电流j_m,其方向在磁层顶局地坐标系的-M方向,即与磁层顶查普曼-费拉罗电流同向,由电子在+M方向的运动(v_(em))携带.这些电流结构具有以下特征:磁鞘与磁层成分混合,磁场为开放形态;离子去磁化,电子与磁场冻结;N方向(即垂直于磁层顶电流片方向)的电场E_n显著增大,幅度达到约20 mV·m^(-1),并伴有明显的尖峰状起伏,该增强和尖峰状起伏的电场对应于霍尔电场.分析表明,电流、电子与离子运动的偏离以及霍尔电场之间遵从广义欧姆定律,三者密切关联.进一步对磁层顶磁重联的探测数据进行分析发现,在很多重联区内也存在与通量绳内相似的结构,其尺度约为d_i量级,其中霍尔电场E_N、电流j_M和电子速度v_(eM)均与通量绳内对应物理量的方向相同且幅度相近.基于上述观测事实,采用经典FtE通量绳模型,对通量绳内电流、电子运动和霍尔电场的起源进行了初步探讨,认为其来源于磁层顶无碰撞磁重联区内的相应结构,并且后者在离子尺度通量绳的形成过程中起到重要作用.

关键词：磁通量绳离子尺度电流霍尔电场磁层顶磁重联

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Surgical management of polycystic liver disease

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World Journal of Gastroenterology 2007年第38期13卷 5052-5059页

作者： Robert t russell c Wright Pinson Vanderbilt University Medical center Department of Hepatobiliary Surgery and Liver Transplantation 1301 22nd Avenue South Nashville TN 37232-5545 United States

Adult polycystic liver disease (PcLD) is an autosomal dominant condition commonly associated with autosomal dominant polycystic kidney disease (ADPKD). However in the last decade, it has been recognized that there is a distinct form of autosomal dominant PcLD that arises without concomitant ADPKD. Early knowledge of the pathogenesis was gained from the study of hepatic cysts in patients with ADPKD. Bile duct overgrowth after embryogenesis results in cystic hepatic dilatations that are known as biliary microhamartomas or von Meyenburg complexes. Further dilatation arises from cellular proliferation and fluid secretion into these cysts. there is a variable, broad spectrum of manifestations of PcLD. Although PcLD is most often asymptomatic, massive hepatomegaly can lead to disabling symptoms of abdominal pain, early satiety, persistent nausea, dyspnea, ascites, biliary obstruction, and lower body edema. complications of PcLD include cyst rupture and cyst infection. Also, there are associated medical problems, especially intracranial aneurysms and valvular heart disease, which clinicians need to be aware of and evaluate in patients with PcLD. In asymptomatic patients, no treatment is indicated for PcLD. In the symptomatic patient, surgical therapy is the mainstay of treatment tailored to the extent of disease for each patient. Management options include cyst aspiration and sclerosis, open or laparoscopic fenestration, liver resection with fenestration, and liver transplantation. the surgical literature discussing treatment of PcLD, including techniques, outcomes, and complication rates, are summarized in this review.

关键词： Polycystic liver disease Fenestration Laparoscopy Liver resection Liver transplantation

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Serological surveillance for SARS-coV-2 antibodies among students,faculty and staff within a large university system during the pandemic

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World Journal of Virology 2025年第1期14卷 99-107页

作者： Marcos G Pinheiro Gabriela G O Alves Maria Eduarda R conde Sofia L costa Regina c S Sant’Anna Isa M F Antunes Mônica c carneiro Fabio S Ronzei Julia c Scaffo Felipe R Pinheiro Lialyz S Andre Helvecio c Povoa Valéria t Baltar Fabíola Giordani Eduarda S Hemerly Gisele c Alexandre Karla c de Paula Márcio Watanabe Antonio claudio L da Nóbrega Jackeline christiane P Lobato Fabio Aguiar-Alves Laboratory of Molecular Epidemiology and Biotechnology Rodolpho Albino University LaboratoryFluminense Federal UniversityNiterói 24241000Rio de JaneiroBrazil Estácio de SáUniversity Nova Friburgo 28611135Rio de JaneiroBrazil Pathology Program Medicine schoolFluminense Federal UniversityNiterói 24070090Rio de JaneiroBrazil Department of Pharmaceutical Sciences Lloyd L.Gregory School of PharmacyPalm Beach Atlantic UniversityWest Palm BeachFL 33401United States Health Institute of Nova Friburgo Fluminense Federal UniversityNova Friburgo 28613001Rio de JaneiroBrazil Department of Epidemiology and Biostatistics Institute of Collective Health(ISC)Fluminense Federal UniversityNiterói 24033900Rio de JaneiroBrazil Institute of Physical Education Fluminense Federal UniversityNiterói 24020005Rio de JaneiroBrazil Department of Statistics Fluminense Federal UniversityNiterói 24210200Rio de JaneiroBrazil Department of Physiology and Pharmacology Fluminense Federal UniversityNiterói 24210130Rio de JaneiroBrazil

BAcKGROUND At the end of December 2019,the world faced severe acute respiratory syndrome-coronavirus 2(SARS-coV-2),which led to the outbreak of coronavirus disease 2019(cOVID-19),associated with respiratory *** virus has shown significant challenges,especially for senior citizens,patients with other underlying illnesses,or those with a sedentary *** tests conducted early on have helped identify how the virus is transmitted and how to curb its *** study hypothesis was that the rapid serological test for SARS-coV-2 antibodies could indicate the immunoreactive profile during the cOVID-19 pandemic in a university *** to conduct active surveillance for serological expression of anti-SARS-coV-2 antibodies in individuals within a university setting during the cOVID-19 *** this sectional study by convenience sampling was conducted in a large university in Niteroi-RJ,Brazil,from March 2021 to July *** study population consisted of students,faculty,and administrative staff employed by the university.A total of 3433 faculty members,60703 students,and 3812 administrative staff were invited to *** were gathered through rapid serological tests to detect immunoglobulin(Ig)M and IgG against ***χ²or Fisher's exact test was used to conduct statistical analysis.A 0.20 significance level was adopted for variable selection in a multiple logistic regression model to evaluate *** A total of 1648 individuals were enrolled in the *** proportion of cOVID-19 positivity was 164/1648(9.8%).the adjusted logistic model indicate a positive association between the expression of IgM or IgG and age[odds ratio(OR)=1.16,95%cI:1.02-1.31](Pcontact with a cOVID-19-positive case(OR=3.49,95%cI:2.34-5.37)(Pthose who had received the cOVID-19 vaccine(OR=2.33,95%cI:1.61-3.35)(Pcial isolation(OR=0.59,95%cI:0.41-0.84)(Pthe likelihood of sho

关键词： Serological surveillance SARS-coV-2 antibodies cOVID-19 Serological rapid test Risk factors for cOVID-19

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Kinematics of whip spider pedipalps: a 3D comparative morpho-functional approach

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Integrative Zoology 2022年第1期17卷 156-167页

作者： Michel ScHMIDt Roland R.MELZER russell D.c.BIcKNELL Bavarian State collection of Zoology Bavarian Natural History CollectionsMunichGermany Department Biology II Ludwig-Maximilians-Universität MünchenMunichGermany GeoBio-center Ludwig-Maximilians-Universität MünchenMunichGermany Palaeoscience Research centre School of Environmental and Rural ScienceUniversity of New EnglandArmidaleAustralia

Amblypygi are tropical and subtropical ambush predators that use elongated,raptorial pedipalps for different *** pedipalp use in predation and courtship has been explored in videography in vivo analyses,kinematic ex vivo examination of these appendages has not been ***,we rectify this lack of data by using microct scans to 3D-kinematically model the appendage morphology and the range of motion(ROM)of the joints for Damon medius and Heterophrynus *** illustrate the successful application of this technique to terrestrial euarthropods in determining the maximum ROM values for each pedipalp *** also note that,in life,these values would be lower due to motion restricting structures like tendons,arthrodial membranes,and *** further compare our maximum values obtained here with data from video-based motion *** ROM of each joint shows the greatest flexibility in the femur-tibia joint(140–150°),the lowest in the basitarsus-claw joint(35–40°).ROM in the tibia-basitarsus joint is markedly distinct(***:44°;***:105°).this disparity reflects how *** uses the joint in the capture basket,while *** uses the femur-tibia joint to form the capture *** further illustrate notable vertical motion of the *** pedipalp compared to *** difference reflects the retro-ventral trochanter apophysis of *** study opens the possibility to further whip spider kinematic *** of other taxa using this approach will result in a more comprehensive understanding of the ecological significance and ethological implications of this unique arachnid group.

关键词： 3D kinematic analyses Amblypygi arthropod joints Autodesk Maya Damon medius Heterophrynus elaphus range of motion analyses

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Energy principle of ferroelectric ceramics and single domain mechanical model

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Acta Mechanica Sinica 2007年第5期23卷 531-543页

作者： t.c.Wang LNM Institute of MechanicsChinese Academy of SciencesBeijing 100080China

Many physical experiments have shown that the domain switching in a ferroelectric material is a complicated evolution process of the domain wall with the variation of stress and electric field. According to this mechanism, the volume fraction of the domain switching is introduced in the constitutive law of ferroelectric ceramic and used to study the nonlinear constitutive behavior of ferroelectric body in this paper. the principle of stationary total energy is put forward in which the basic unknown quantities are the displacement ui, electric displacement Di and volume fraction pI of the domain switching for the variant I. Mechanical field equation and a new domain switching criterion are obtained from the principle of stationary total energy. the domain switching criterion proposed in this paper is an expansion and development of the energy criterion. On the basis of the domain switching criterion, a set of linear algebraic equations for the volume fraction PI of domain switching is obtained, in which the coefficients of the linear algebraic equations only contain the unknown strain and electric fields. then a single domain mechanical model is proposed in this paper. the poled ferroelectric specimen is considered as a transversely isotropic single domain. By using the partial experimental results, the hardening relation between the driving force of domain switching and the volume fraction of domain switching can be calibrated. then the electromechanical response can be calculated on the basis of the calibrated hardening relation. the results involve the electric butterfly shaped curves of axial strain versus axial electric field, the hysteresis loops of electric displacement versus electric filed and the evo- lution process of the domain switching in the ferroelectric specimens under uniaxial coupled stress and electric field loading. the present theoretic prediction agrees reasonably with the experimental results given by Lynch.

关键词： Ferroelectric ceramic Domain switching the volume fraction of domain switching Single domain mechanical model

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MULtI-FAcILItY ORDERED MEDIAN PROBLEMS IN DIREctED NEtWORKS

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Journal of Systems Science & complexity 2011年第1期24卷 61-67页

作者： Huajun tANG t. c. Edwin cHENG c. t. NG Faculty of Management and Administration Macao University of Science and Technology Macao China Department of Logistics and Maritime Studies The Hong Kong Polytechnic University Hong Kong China

this paper uses a finite dominating set （FDS） to investigate the multi-facility ordered median problem （OMP） in a strongly connected directed network. the authors first prove that the multi-facility OMP has an FDS in the node set, which not only generalizes the FDS result provided by Kalcsics, et al. （2002）, but also extends the FDS result from the single-facility case to the multiple case, filling an important gap. then, based on this FDS result, the authors develop an exact algorithm to solve the problem. However, if the number of facilities is large, it is not practical to find the optimal solution, because the multi-facility OMP in directed networks is NP-hard. Hence, we present a constant-approximation algorithm for the p-median problem in directed networks. Finally, we pose an open problem for future research.

关键词： Algorithms finite dominating sets multi-facility ordered median problem pseudoequilibria.

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Hematopoietic stem cell-derived adipocytes and fibroblasts in the tumor microenvironment

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World Journal of Stem cells 2015年第2期7卷 253-265页

作者： Ying Xiong Lindsay t Mc Donald Dayvia L russell Ryan R Kelly Katie R Wilson Meenal Mehrotra Adam c Soloff Amanda c LaRue Research Services Ralph H Johnson Veterans Affairs Medical Center Department of Pathology and Laboratory Medicine Ralph H Johnson Veterans Affairs Medical Center the Hollings cancer center Medical University of South CarolinaRalph H Johnson Veterans Affairs Medical Center Department of Microbiology and Immunology Ralph H Johnson Veterans Affairs Medical Center

the tumor microenvironment(tME) is complex and constantly evolving. this is due, in part, to the crosstalk between tumor cells and the multiple cell types that comprise the tME, which results in a heterogeneous population of tumor cells and tME cells. this review will focus on two stromal cell types, the cancerassociated adipocyte(cAA) and the cancer-associated fibroblast(cAF). In the clinic, the presence of cAAs and cAFs in the tME translates to poor prognosis in multiple tumor types. cAAs and cAFs have an activated phenotype and produce growth factors, inflammatory factors, cytokines, chemokines, extracellular matrix components, and proteases in an accelerated and aberrant fashion. through this activated state, cAAs and cAFs remodel the tME, thereby driving all aspects of tumor progression, including tumor growth and survival, chemoresistance, tumor vascularization, tumor invasion, and tumor cell metastasis. Similarities in the tumorpromoting functions of cAAs and cAFs suggest that a multipronged therapeutic approach may be necessary to achieve maximal impact on disease. While cAAs and cAFs are thought to arise from tissues adjacent to the tumor, multiple alternative origins for cAAs and cAFs have recently been identified. Recent studies from our lab and others suggest that the hematopoietic stem cell, through the myeloid lineage, may serve as a progenitor for cAAs and cAFs. We hypothesize that the multiple origins of cAAs and cAFs may contribute to the heterogeneity seen in the tME. thus, a better understanding of the origin of cAAs and cAFs, how this origin impacts their functions in the tME, and thetemporal participation of uniquely originating tME cells may lead to novel or improved anti-tumor therapeutics.

关键词： Hematopoietic stem cell cancer associatedadipocyte Mesenchymal stromal cell tumor progression cancer associated fibroblast Plasticity Metastasis Fibrocyte

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地球内磁层场向电流的统计特征

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地球物理学报 1997年第4期40卷 453-459页

作者：焦维新肖佐 c.t.russell 北京大学地球物理系北京100871 IGPP UniversityofCalifornia

利用ISEE－1和ISEE-2飞船观测的磁场数据，分析了地球内磁层场向电流的统计特征，包括场向电流的空间（L值和地方时）分布；流进和流出电离层的场向电流随地方时的变化；场向电流发生率与地磁活动水平（以AL指数表征）、行星际磁场（IMF... 详细信息

利用ISEE－1和ISEE-2飞船观测的磁场数据，分析了地球内磁层场向电流的统计特征，包括场向电流的空间（L值和地方时）分布；流进和流出电离层的场向电流随地方时的变化；场向电流发生率与地磁活动水平（以AL指数表征）、行星际磁场（IMF）Bz的关系，电流强度和密度随地磁活动水平的变化等．发现，场向电流大都发生在夜间，且集中在L为6—10区域内，场向电流发生率，强度和密度随地磁活动增强而增大，行星际磁场南向时的发生率远远高于北向时的发生率．这些结果表明，内磁层场向电流的产生是太阳风和磁层、电离层间电动耦合增加的结果．

关键词：场向电流行星陆磁场 AL指数内磁层场磁场

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