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Cortical hem signaling center: functions, development, and potential implications for evolution and brain disorders

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Neural Regeneration Research 2025年第4期20卷 1079-1080页

作者： victor v.Chizhikov Igor y.Iskusnykh Department of Anatomy and Neurobiology University of Tennessee Health Science CenterMemphisTNUSA

Development of the telencephalon relies upon several signaling centers-localized cellular populations that supply secreted factors to pattern the cortical *** such signaling center is the cortical hem,which arises during embryonic development at the telencephalic dorsal midline,adjacent to the choroid plexus and hippocampal primordium(Figure 1A).While the cortical hem has also been described in reptiles and birds,most of our knowledge about the developmental roles of the cortical hem is derived from the analysis in *** cortical hem produces several types of secreted molecules,including wingless-related integration site(Wnt)and bone morphogenetic(Bmp)*** cortical hem is particularly important for the development of the hippocampus,which is involved in learning and memory,and the neocortex,which is the most complex brain region that mediates multiple types of behavior and higher cognitive functions(Mangale et al.,2008;Dal-valle-Anton and Borrell,2022).

关键词： epithelium Figure center

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

Solar wind entry via flux tube into magnetosphere observed by Cluster measurements at dayside magnetopause during southward IMF

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Science China(Technological Sciences) 2009年第7期52卷 2104-2111页

作者： M. Dunlop A. Balogh H. Rème y. v. bogdanova A. Fazakerley Rutherford Appleton Laboratory Didcot United Kingdom Imperial College of Science Technology and Medicine London United Kingdom CESR BP4346 31028 Toulouse Cedex 4 France Mullard Space Science Laboratory Dorkink United Kingdom Department of Physics La Trobe University Victoria 3086 Australia

By analyzing hot ion and electron parameters together with magnetic field measurements from Cluster, an event of magnetopause crossing of the spacecraft has been investigated. At the latitude of about 40° and magnetic local time (MLT) of 13:20 during the southward interplanetary magnetic field (IMF), a transition layer was observed, with the magnetospheric field configuration and cold dense plasma features of the magnetosheath. The particle energy-time spectrograms inside the layer were similar to but still a little different from those in the magnetosheath, obviously indicating the solar wind entry into the magnetosphere. The direction and magnitude of the accelerated ion flow implied that reconnection might possibly cause such a solar wind entry phenomenon. The bipolar signature of the normal magnetic component BN in magnetopause coordinates further supported happening of reconnection there. The solar wind plasma flowed toward the magnetopause and entered the magnetosphere along the reconnected flux tube. The magnetospheric branch of the reconnected flux tube was still inside the magnetosphere after reconnection and supplied the path for the solar wind entry into the dayside magnetosphere. The case analysis gives observational evidence and more details of how the reconnection process at the dayside low latitude magnetopause caused the solar wind entry into the magnetosphere.

关键词： transport process magnetic reconnection solar wind-magnetosphere interactions

Magnetospheric Boundary Layer Structure and Dynamics as Seen From Cluster and Double Star Measurements

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空间科学学报 2013年第6期33卷 577-603页

作者： y v bogdanova C J Owen M W Dunlop M G G T Taylor A N Fazakerley Space Science and Technology Department RALChiltonDidcotOxfordshireOX11 0QXUK Mullard Space Science Laboratory University College LondonHolmbury St.MaryDorkingSurreyRH5 6NTUK Science and Robotic Exploration Directorate ESA/ESTECNoordwijkThe Netherlands

In this review,we discuss the structure and dynamics of the magnetospheric LowLatitude Boundary Layer(LLBL)based on recent results from multi-satellite missions Cluster and Double *** boundary layer,adjacent to the magnetopause on the magnetospheric side,usually consists of a mixture of plasma of magnetospheric and magnetosheath origins,and plays an important role in the transfer of mass and energy from the solar wind into the magnetosphere and subsequent magnetospheric *** southward Interplanetary Magnetic Field(IMF)conditions,this boundary layer is generally considered to be formed as a result of the reconnection process between the IMF and magnetospheric magnetic field lines at the dayside magnetopause,and the structure and plasma properties inside the LLBL can be understood in terms of the time history since the reconnection *** northward IMF conditions,the LLBL is usually thicker,and has more complex structure and *** observations confirm that the LLBL observed at the dayside can be formed by single lobe reconnection,dual lobe reconnection,or by sequential dual lobe reconnection,as well as partially by localized cross-field *** LLBL magnetic topology and plasma signatures inside the different sub-layers formed by these processes are discussed in this *** role of the Kelvin-Helmholtz instability in the formation of the LLBL at the flank magnetopause is also ***,we conclude that the LLBL observed at the flanks can be formed by the combination of processes,(dual)lobe reconnection and plasma mixing due to non-linear Kelvin-Helmholtz waves.

关键词：边界层结构磁层顶双星群集国际货币基金组织等离子体特性测量拓扑结构

Simulation of detection and scattering of sound waves by the lateral line of a fish

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Chinese Physics B 2022年第2期31卷 398-404页

作者： v M Adamyan I y Popov I v Blinova v v Zavalniuk Odessa I.I.Mechnikov National University Dvoryanskaya Str.2Odesa65082Ukraine ITMO University Kronverkskiy49Saint Petersburg197101Russia Odessa Military Academy 10 Fontanska RoadOdesa 65009Ukraine

A solvable model of lateral line of a fish based on a wave equation with additional boundary conditions on a set of isolated points is *** the framework of this model it is shown that the ratio of pressures on lateral lines on different fish flanks,as well as the cross section of sound scattering on both the lines,strongly depends on angles of incidence of incoming sound *** strong angular dependence of the pressure ratio seems to be sufficient for the fish to determine the directions from which the sound is coming.

关键词： acoustic equation point self-adjoint perturbations of Laplace operator scattering lateral line

On the l_2-stability of time-varying linear and nonlinear discrete-time MIMO systems

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Control Theory and Technology 2014年第3期12卷 250-274页

作者： y.v.vENKATESH Department of ECE National University of SingaporeSingapore Electrical Sciences Indian Institute of ScienceBangalore India

New conditions are derived for the l2-stability of time-varying linear and nonlinear discrete-time multiple-input multipleoutput （MIMO） systems, having a linear time time-invariant block with the transfer function F（z）, in negative feedback with a matrix of periodic/aperiodic gains A（k）, k = 0,1, 2,... and a vector of certain classes of non-monotone/monotone nonlinearities φp（-）, without restrictions on their slopes and also not requiring path-independence of their line integrals. The stability conditions, which are derived in the frequency domain, have the following features： i） They involve the positive definiteness of the real part （as evaluated on ｜z｜ = 1） of the product of Г （z） and a matrix multiplier function of z. ii） For periodic A（k）, one class of multiplier functions can be chosen so as to impose no constraint on the rate of variations A（k）, but for aperiodic A（k）, which allows a more general multiplier function, constraints are imposed on certain global averages of the generalized eigenvalues of （A（k ＋ 1）,A（k））, k = 1, 2 iii） They are distinct from and less restrictive than recent results in the literature.

关键词： Circle criterion Discrete-time MIMO system l2-stability Feedback system stability Linear matrix inequalities (LMI) Lur'e problem Multiplier functions Nyquist's criterion Periodic coefficient systems Popov's criterion Time-varying systems

Cluster observations of high-altitude cusp during multiple fast-turning IMF

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Chinese Science Bulletin 2010年第22期55卷 1178-1185页

作者： CAI HongTao MA Shuying DUNLOP M W bogdanova y DAvIES J A PITOUT F School of Electronic Information Wuhan University Wuhan 430079 China Key Lab of Geospace Environment and Geodesy CNEM Wuhan 430079 China SSTD Rutherford Appleton Laboratory Chilton OX11 OQX UK Department of Physics La Trobe University Melbourne Victoria 3086 Australia Max-Planck-lnstitut fiir Extraterrestrische Physik Garching D-37191 Germany

Using coordinated observations from the Cluster,DMSP and ESR radar,high-altitude cusp was investigated for a time period characterized by four fast reversals of the IMF *** February 12,2003,Cluster was flying sunward at duskside over the Northern Hemisphere,across the high-altitude northern cusp *** the two crossings are during steady northward IMF interval,whereas ion fluxes detected during the time period are quite *** cusp in the first crossing is a "typical" northward-IMF one,with short-lived ion injections of evident "reversed" dispersion *** the second crossing,however,the cusp appears to be a region reminiscent of the Stagnant Exterior Cusp (SEC).In addition,evident upward-flowing O+ ion bursts,possibly original from polar ionosphere,are also detected during the second cusp crossing,together with enhancement of trapped magnetospheric-like electron *** suggest that the SEC-like cusp is likely on newly closed field lines,which were first reconnected (being opened) at low latitudes and later reconnected again (being closed) poleward of the northern cusp.

关键词：国际货币基金组织高海拔群集观测十字路口离子检测低纬度地区气象卫星

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Travel time prediction with viscoelastic traffic model

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Applied Mathematics and Mechanics(English Edition) 2018年第12期39卷 1769-1788页

作者： yongliang ZHANG M.N.SMIRNOvA A.I.bogdanova Zuojin ZHU N.N.SMIRNOv Faculty of Engineering Science University of Science and Technology of China Faculty of Mechanics and Mathematics Moscow M.V.Lomonosov State University Scientific Research Institute for System Analysis Russian Academy of Sciences

Travel time through a ring road with a total length of 80 km has been predicted by a viscoelastic traffic model(vEM), which is developed in analogous to the non-Newtonian fluid flow. The vEM expresses a traffic pressure for the unfree flow case by space headway, ensuring that the pressure can be determined by the assumption that the relevant second critical sound speed is exactly equal to the disturbance propagation speed determined by the free flow speed and the braking distance measured by the average vehicular length. The vEM assumes that the sound speed for the free flow case depends on the traffic density in some specific aspects, which ensures that it is exactly identical to the free flow speed on an empty road. To make a comparison, the open Navier-Stokes type model developed by Zhang(ZHANG, H. M. Driver memory, traffic viscosity and a viscous vehicular traffic flow model. Transp. Res. Part B, 37, 27–41(2003)) is adopted to predict the travel time through the ring road for providing the counterpart *** the traffic free flow speed is 80 km/h, the braking distance is supposed to be 45 m,with the jam density uniquely determined by the average length of vehicles l ≈ 5.8 m. To avoid possible singular points in travel time prediction, a distinguishing period for time averaging is pre-assigned to be 7.5 minutes. It is found that the travel time increases monotonically with the initial traffic density on the ring road. Without ramp effects, for the ring road with the initial density less than the second critical density, the travel time can be simply predicted by using the equilibrium speed. However, this simpler approach is unavailable for scenarios over the second critical.

关键词： travel time viscoelastic modeling distinguishing period for time averaging spatial-temporal pattern traffic jam

Renewable energy based microgrid system sizing and energy management for green buildings

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Journal of Modern Power Systems and Clean Energy 2015年第1期3卷 1-13页

作者： y.v.PAvAN KUMAR Ravikumar BHIMASINGU Department of Electrical Engineering Indian Institute of Technology Hyderabad(IITH)HyderabadIndia

The objective of this paper is to model a hybrid power system for buildings,which is technically feasible and economically *** a view to promote renewable energy sources,photovoltaics and wind turbines are integrated with the grid connected *** system is modeled and the optimal system configuration is estimated with the help of hybrid optimization model for electric renewables(HOMER).The logic is illustrated with a case study based on the practical data of a building located in southern *** building is associated with 3.4 MWh/day priority load(peak load as 422 kW),as well as 3.3 MWh/day deferrable load(peak load as 500 kW).Sensitivity analysis is performed to deal with uncertainties such as the increase in electricity consumption and grid tariff,environmental changes,*** the simulation result,it is observed that the designed system is cost effective and environment friendly,which leads to 6.18%annual cost savings and reduces CO_(2) emissions by 38.3%.Sensitivity results indicate that the system is optimal and adaptable in a certain range of unanticipated variances with respect to best estimated ***,an energy management strategy is developed for the optimal system to ensure reliable power during contingency and *** green and hybrid power system designed can be adaptable to any critical and large consumers of urban buildings.

关键词： Renewable energy sources(RES) Hybrid power systems(HPS) Photovoltaic(Pv) Wind turbine(WT) Low-carbon electricity Energy management Total net present cost(TNPC)