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High Power Laser Science and Engineering 2016年第2期4卷 80-84页

作者： Ryuji Itakura Takayuki Kumada motoyoshi nakano Hiroshi Akagi Kansai Photon Science Institute National Institutes for Quantum and Radiological Science and Technology(QST) Nuclear Science and Research Institute Japan Atomic Energy Agency Department of Chemistry Graduate School of ScienceTohoku University

We demonstrate that the methodology of frequency-resolved optical gating(FROG) is applicable to time-resolved reflection spectroscopy of a plasma mirror in the vacuum-ultraviolet(VUV) region. Our recent study [R. Itakura et al. Opt. Express 23, 10914(2015)] has shown that a VUV waveform can be retrieved from a VUV reflection spectrogram of a plasma mirror formed on a fused silica(FS) surface by irradiation with an intense femtosecond laser pulse. Simultaneously, the increase in the reflectivity with respect to the Fresnel reflection of the unexcited FS surface can be obtained as a time-dependent reflectivity of the plasma mirror. In this study, we update the FROG analysis procedure using the least-square generalized projections algorithm. This procedure can reach convergence much faster than the previous one and has no aliasing problem. It is demonstrated that a significantly chirped VUV pulse as long as 1 ps can be precisely characterized.

关键词： frequency-resolved optical gating least-square generalized projections algorithm plasma mirror vacuum ultraviolet

Structures of Stoichiometric Sodium Oxide Cluster Cations Studied by Ion Mobility Mass Spectrometry

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Chinese Journal of Chemical Physics 2019年第2期32卷 193-199,I0002页

作者： motoyoshi nakano Yudai Ishimura Riki Hotta Daiki Hebiguchi Toshiaki Nagata Fuminori Misaizu Institute for Excellence in Higher Education Tohoku University 41 Kawauchi Aoba-ku Sendai 980-8576 Japan Department of Chemistry Graduate School of Science Tohoku University 6-3 Aoba Aramaki Aoba-ku Sendai 980-8578 Japan

Structures of stable compositions of sodium oxide cluster cations (NanOm+,n≤11) have been investigated by ion mobility mass spectrometry. Stoichiometric compositions series, Na(Na2O)(n-1)/2^+(n=3, 5, 7, 9, and 11), were observed as stable composition series, and NaO(Na2O)(n-1)/2^+ series (n=5, 7, 9, and 11) were observed as secondary stable series in the mass spectra. To assign the structures of these cluster ion series, collision cross sections between the ions and helium buffer gas were determined experimentally from the ion mobility measurements. Theoretical collision cross sections were also calculated for optimized structures of these compositions. Finally, the structures of Na(Na2O)(n-1)/2^+ and NaO(Na2O)(n-1)/2^+ were assigned to those having similar structural frames for each n except for n=9. All bonds in the assigned structures of Na(Na2O)(n-1)/2^+ were between sodium and oxygen. On the other hand, there was one O-O bond in addition to Na-O bonds in NaO(Na2O)(n-1)/2^+. This result indicates that NaO(Na2O)(n-1)/2^+ have a peroxide ion (O22-) as a substitute for an oxide ion (O2-) of Na(Na2O)(n-1)/2^+. As a result, both stable series, Na(Na2O)(n-1)/2^+ and NaO(Na2O)(n-1)/2^+, are closed-shell compositions. These closed-shell characteristics have a strong influence on the stability of sodium oxide cluster cations.

关键词： Sodium oxide cluster Structure Ion mobility mass spectrometry

Non-cooperative optimization games in market-oriented overlay networks： an integrated model of resource pricing and network formation

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Frontiers of Computer Science 2011年第4期5卷 496-505页

作者： Yutaka OKAIE Tadashi nakano Graduate School of Engineering Osaka University Suita Osaka 565-0871 Japan

In this paper, we formulate a non-cooperative optimization game in market-oriented overlay networks where participating peers share their own computing resources to earn virtual money called energy. We model an overlay network as a set of non-cooperative resource providing peers, called platforms, that perform resource pricing and topology management to maximize their own energy gains. Resource consuming peers, called agents, are simply designed to migrate platform-to-platform to find the least expensive resources in the network. Simulation results are presented to demonstrate the market dynamics as well as the global properties of the network, i.e., resource price and network topology, that emerge from local interactions among the group of peers.

关键词： Overlay networks market mechanisms non-cooperative games mobile agents

Potential effects of mesenchymal stem cell derived extracellular vesicles and exosomal miRNAs in neurological disorders

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Neural Regeneration Research 2021年第12期16卷 2359-2366页

作者： Masako nakano Mineko Fujimiya Department of Anatomy Sapporo Medical University School of MedicineSapporoHokkaidoJapan

Mesenchymal stem cells are multipotent cells that possess anti-inflammatory,antiapoptotic and immunomodulatory *** effects of existing drugs for neurodegenerative disorders such as Alzheimer’s disease are limited,thus mesenchymal stem cell therapy has been anticipated as a means of ameliorating neuronal *** mesenchymal stem cells are known to scarcely differentiate into neuronal cells in damaged brain after transplantation,paracrine factors secreted from mesenchymal stem cells have been suggested to exert therapeutic *** vesicles and exosomes are small vesicles released from mesenchymal stem cells that contain various molecules,including proteins,mRNAs and *** recent years,administration of exosomes/extracellular vesicles in models of neurological disorders has been shown to improve neuronal dysfunctions,via exosomal transfer into damaged *** addition,various microRNAs derived from mesenchymal stem cells that regulate various genes and reduce neuropathological changes in various neurological disorders have been *** review summarizes the effects of exosomes/extracellular vesicles and exosomal microRNAs derived from mesenchymal stem cells on models of stroke,subarachnoid and intracerebral hemorrhage,traumatic brain injury,and cognitive impairments,including Alzheimer’s disease.

关键词： exosomes extracellular vesicles mesenchymal stem cells microRNA neurological disorders

Novel Phase Transition in BaPr_2Mn_2O_7

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Journal of Rare Earths 2006年第Z2期24卷 1-3页

作者： Hiromi nakano Naoki Kamegashira Ryukoku University SetaOtsu 520-2194Japan Toyohashi University of Technology Tenpaku-choToyohashi 441-8580Japan

The rare earth manganite BaLn2Mn2O7(Ln = rare earth element) has a Sr3Ti2O7-type layered perovskite structure with double-block oxygen octahedra belonging to the Ruddlesden-Popper-type homologous series AO(ABO3)2. In Pr-manganite, a novel phase transition was first observed in situ at 1040 K by a thermal transmission electron microscope. At 1040 K, reflections began to split along the c-direction in the selected area diffraction pattern. This indicates that a new phase appears in the original phase matrix; the c length of the new phase is 1.5% longer than that of the original phase. After about 5 min, the original phase disappears. No change in the crystal symmetry (space group 14/mmm) is observed above 1040 K.

关键词： rare earth manganite phase transition transmission electron microscope (TEM)

Effect of Exit Geometry of Tail Pipe on the Performance of Pulse Jet Engines

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Journal of Thermal Science 2006年第3期15卷 263-268页

作者： Toshihiro nakano ShigeruMATSUO KenbuTERAMOTO ToshiakiSETOGUCHI Department of Mechanical Engineering Saga University1 Honjo-machiSaga-shiSaga 840-8502Japan

In this paper,the effect of geometries of tube open end on the shock,compression and expansion wavespropagating in the tube was investigated numerically and *** of them is a conventional straightshock tube with an open *** other has a divergent tail tube at the *** a divergent tail tube(flaretube)to an open end shock tube,the period of one-cycle process could be shortened and the pressure behind theexpansion wave produced at the exit of the shock tube could be lowered much more below the atmosphericpressure than that produced in the straight *** results suggested that the intake air into the engine wassignificantly increased by applying a flare tube instead of a straight tube.

关键词： compressible flow shock wave expansion wave pulse jet numerical simulation

Methane emissions from wetlands on the Qinghai-Tibet Plateau

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Chinese Science Bulletin 1999年第24期44卷 2282-2286页

作者： nakano Tomoko Department of Geography Tokyo Metropolitan University 192-03 Japan

The areal extent of cold freshwater wetlands on the Qinghai-Tibet Plateau (QTP) is estimated at 0.133 × 106 km2, suggesting a significant methane potential. Methane fluxes from wet alpine meadows, peatlands, Hippuris vulgaris mires and secondary marshes were 43.18, 12.96, -0.28 and 45.90 mgf33m-2f33d-1, respectively based on the transect flux studies at the Huashixia Permafrost Station (HPS) from July to August 1996. Average CH4 fluxes in the

关键词： QTP wetland ecosystems CH4 emission spatiality and seasonality fluxes.

A New Approach to Graph Recognition and Applications to Distance-Hereditary Graphs

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Journal of Computer Science & Technology 2009年第3期24卷 517-533页

作者： Shin-ichi nakano Ryuhei Uehara Takeaki Uno Department of Computer Science Faculty of EngineeringGunma UniversityGunma 376-8515Japan School of Information Science Japan Advanced Institute of Science and TechnologyIshikawa 923-1292Japan National Institute of Informatics Tokyo 101-8430Japan

Algorithms used in data mining and bioinformatics have to deal with huge amount of data efficiently. In many applications, the data are supposed to have explicit or implicit structures. To develop efficient algorithms for such data, we have to propose possible structure models and test if the models are feasible. Hence, it is important to make a compact model for structured data, and enumerate all instances efficiently. There are few graph classes besides trees that can be used for a model. In this paper, we investigate distance-hereditary graphs. This class of graphs consists of isometric graphs and hence contains trees and cographs. First, a canonical and compact tree representation of the class is proposed. The tree representation can be constructed in linear time by using prefix trees. Usually, prefix trees are used to maintain a set of strings. In our algorithm, the prefix trees are used to maintain the neighborhood of vertices, which is a new approach unlike the lexicographically breadth-first search used in other studies. Based on the canonical tree representation, efficient algorithms for the distance-hereditary graphs are proposed, including linear time algorithms for graph recognition and graph isomorphism and an efficient enumeration algorithm. An efficient coding for the tree representation is also presented; it requires [3.59n] bits for a distance-hereditary graph of n vertices and 3n bits for a cograph. The results of coding improve previously known upper bounds （both are 2^O（nlogn）） of the number of distance-hereditary graphs and cographs to 2^[3.59n] and 2^3n, respectively.

关键词： algorithmic graph theory cograph distance-hereditary graph prefix tree tree representation

CREB-binding proteins (CBP) as a transcriptional coactivator of GATA-2

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Science China(Life Sciences) 2008年第3期51卷 191-198页

作者： TOMOMI Takahashi TORU nakano Department of Pathology Medical School and Graduate School of Frontier Biosciences Osaka University Yamada-oka 2-2 Suita Osaka 565-0871 Japan

The GATA family consists of six members, GATA 1-6. In this study, we focused on GATA-2, which is expressed predominantly in hematopoietic progenitor cells and plays the key role in keeping these cells in the undifferentiated status. CREB-binding proteins (CBP) are essential transcriptional coacti- vators for a large number of regulated DNA-binding transcription factors, including GATA-1. But there have been no reports on whether CBP is still a co-activator of GATA-2. Here, we used the immunopre- cipitation and pull-down experiments to show that the GATA-2 and CBP were physically binding to- gether, and clarified the binding sites CH1, CH3 , CH452 and CT1430 in CBP and N-finger, C-finger and N-C-finger in GATA-2. Luciferase assay results in our experiment indicated that CBP could increase GATA-2 transcriptional activity in the dose-dependent manner. GATA-1 is mainly expressed in differen- tiated hematopoietic cells, but still has overlap expression with GATA-2. CBP is a coactivator of GATA-2 and GATA-1. The investigation on the mechanism that could decide whether CBP binds to GATA-2 to keep hematopoietic cells in the progenitor status or to GATA-1 to start differentiation will be a very in- teresting and very meaningful project in the near future.

关键词： CBP TATA-2 coactivator hematopoietic cells

Enhanced vibrational resonance in a single neuron with chemical autapse for signal detection

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Chinese Physics B 2020年第12期29卷 556-563页

作者： Zhiwei He Chenggui Yao Jianwei Shuai Tadashi nakano Department of Mathematics Shaoxing UniversityShaoxing 312000China College of Mathematics Physics and Information EngineeringJiaxing UniversityJiaxing 314000China Department of Physics State Key Laboratory of Cellular Stress BiologyInnovation Center for Cell Signaling NetworkXiamen UniversityXiamen 361102China Graduate School of Frontier Biosciences Osaka University5408570Japan

Many animals can detect the multi-frequency signals from their external *** understanding for underlying mechanism of signal detection can apply the theory of vibrational resonance,in which the moderate high frequency driving can maximize the nonlinear system's response to the low frequency subthreshold *** this work,we study the roles of chemical autapse on the vibrational resonance in a single neuron for signal *** reveal that the vibrational resonance is strengthened significantly by the inhibitory autapse in the neuron,while it is weakened typically by the excitatory *** is generally believed that the inhibitory synapse has a suppressive effect in neuronal ***,we find that the detection of the neuron to the low frequency subthreshold signal can be improved greatly by the inhibitory *** finding indicates that the inhibitory synapse may act constructively on the detection of weak signal in the brain and neuronal system.

关键词： neuronal dynamics autapse vibrational resonance synchronization time delay