Details of the Researcher

PHOTO

Masayuki Imai
Section
Graduate School of Science
Job title
Professor
Degree

  • 博士（工学）（京都大学）

  • 理学修士（大阪大学）

Committee Memberships 2

  • 日本中性子科学会　評議員

    2011/04 - 2013/03

  • 日本中性子科学会　評議員

    2011/04 - 2013/03

Professional Memberships 4

  • Japanese Society of Neutron Science

  • American Chemical Society

  • Biophysical Society

  • Physical Society of Japan

Research Interests 3

  • protocell

  • biophysics

  • soft matter

Research Areas 1

  • Natural sciences / Bio-, chemical, and soft-matter physics /

Papers 158

  1. Temperature dependence of membrane viscosity of ternary lipid GUV with Lo domains

    Julia Tanaka, Kenya Haga, Naohito Urakami, Masayuki Imai, Yuka Sakuma

    Biophysical Journal　124　(5)　818-828　2025/03

    Publisher: Elsevier BV

    DOI： 10.1016/j.bpj.2025.01.024 　

    ISSN： 0006-3495

  2. Translocation of a daughter vesicle in a model system of self-reproducing vesicles Peer-reviewed

    Manit Klawtanong, Yuka Sakuma, Masayuki Imai, Toshihiro Kawakatsu, Petch Khunpetch

    Physics of Fluids　36　(2)　027112-1-9　2024/02/01

    Publisher: AIP Publishing

    DOI： 10.1063/5.0186977 　

    ISSN： 1070-6631

    eISSN： 1089-7666

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    Translocation of a daughter vesicle from a mother vesicle through a pore is experimentally studied by many groups using a model system of self-reproducing vesicles. However, the theoretical formulation of the problem is not fully understood. In the present study, we present a theoretical formulation of the process based on our previous work [P. Khunpetch et al., Phys. Fluids 33, 077103 (2021)]. In our previous work, we considered the daughter vesicle as a rigid body. In the present work, however, we allow the daughter vesicle to deform during the expulsion process. We thus derive the free energy constituting of the elastic moduli of both the mother and daughter vesicles, and of pressure-driven contribution. The minimum energy path of the translocation is searched by using the string method. With use of experimentally reasonable values of the elastic moduli, our improved model successfully reproduced the progress of the birthing process where there is no free energy barrier between the initial and the final states. The equations of motion of the daughter vesicle have been derived within the framework of the Onsager principle. We found that the translocation time of the daughter vesicle can be reduced when the pressure inside the mother vesicle increases, or the initial size of the daughter vesicle decreases.

  3. Effects of grafted polymers on the lipid membrane fluidity

    Yuka Sakuma, Nana Kayamori, Julia Tanaka, Kenya Haga, Masayuki Imai, Toshihiro Kawakatsu

    Biophysical Journal　123　(4)　489-501　2024/02

    Publisher: Elsevier BV

    DOI： 10.1016/j.bpj.2024.01.014 　

    ISSN： 0006-3495

  4. Osmotic spawning vesicle

    Minoru Kurisu, Masayuki Imai

    Soft Matter　20　(45)　8976-8989　2024

    Publisher: Royal Society of Chemistry (RSC)

    DOI： 10.1039/d4sm00915k 　

    ISSN： 1744-683X

    eISSN： 1744-6848

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    We discovered a novel division mechanism of vesicles. This simple and highly productive system will provide proliferation ability to existing and future microcompartment systems, simply by selecting suitable membrane compositions and osmolytes.

  5. Synthesising a minimal cell with artificial metabolic pathways

    Minoru Kurisu, Ryosuke Katayama, Yuka Sakuma, Toshihiro Kawakatsu, Peter Walde, Masayuki Imai

    Communications Chemistry　6　(1)　56-1-14　2023/03/28

    Publisher: Springer Science and Business Media LLC

    DOI： 10.1038/s42004-023-00856-y 　

    eISSN： 2399-3669

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    Abstract A “synthetic minimal cell” is considered here as a cell-like artificial vesicle reproduction system in which a chemical and physico-chemical transformation network is regulated by information polymers. Here we synthesise such a minimal cell consisting of three units: energy production, information polymer synthesis, and vesicle reproduction. Supplied ingredients are converted to energy currencies which trigger the synthesis of an information polymer, where the vesicle membrane plays the role of a template. The information polymer promotes membrane growth. By tuning the membrane composition and permeability to osmolytes, the growing vesicles show recursive reproduction over several generations. Our “synthetic minimal cell” greatly simplifies the scheme of contemporary living cells while keeping their essence. The chemical pathways and the vesicle reproduction pathways are well described by kinetic equations and by applying the membrane elasticity model, respectively. This study provides new insights to better understand the differences and similarities between non-living forms of matter and life.

  6. Concepts of a synthetic minimal cell: Information molecules, metabolic pathways, and vesicle reproduction

    Minoru Kurisu, Masayuki Imai

    Biophysics and Physicobiology　21　e210002-1-16　2023

    Publisher: Biophysical Society of Japan

    DOI： 10.2142/biophysico.bppb-v21.0002 　

    eISSN： 2189-4779

  7. Morphology of vesicle triplets: shape transformation at weak and strong adhesion limits

    Toshikaze Chiba, Yuka Sakuma, Masayuki Imai, Primož Ziherl

    Soft Matter　19　(23)　4286-4296　2023

    Publisher: Royal Society of Chemistry (RSC)

    DOI： 10.1039/d3sm00308f 　

    ISSN： 1744-683X

    eISSN： 1744-6848

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    We investigate the morphologies of adhering vesicle triplets (triangular and linear topologies) in strong and weak adhesion regimes.

  8. From Vesicles toward Protocells and Minimal Cells

    Masayuki Imai, Yuka Sakuma, Minoru Kurisu, Peter Walde

    Soft Matter　2022

    Publisher: Royal Society of Chemistry (RSC)

    DOI： 10.1039/d1sm01695d 　

    ISSN： 1744-683X

    eISSN： 1744-6848

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    In contrast to ordinary condensed matter systems, “living systems” are unique. They are based on molecular compartments that reproduce themselves through (i) an uptake of ingredients and energy from the...

  9. Birthing of a daughter vesicle in a model system for self-reproduction vesicles

    Petch Khunpetch, Yuka Sakuma, Masayuki Imai, Toshihiro Kawakatsu

    Physics of Fluids　33　(7)　077103-077103　2021/07

    Publisher: AIP Publishing

    DOI： 10.1063/5.0052248 　

    ISSN： 1070-6631

    eISSN： 1089-7666

  10. Application of an enzymatic cascade reaction for the synthesis of the emeraldine salt form of polyaniline Peer-reviewed

    Minoru Kurisu, Reinhard Kissner, Masayuki Imai, Peter Walde

    Chemical Papers　75　(10)　5071-5085　2021/04/13

    Publisher: Springer Science and Business Media LLC

    DOI： 10.1007/s11696-021-01620-z 　

    ISSN： 2585-7290

    eISSN： 1336-9075

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    <title>Abstract</title>The synthesis of the emeraldine salt form of polyaniline (PANI-ES) from aniline with <italic>Aspergillus</italic> sp. glucose oxidase (GOD), <sc>d</sc>-glucose, dissolved O2, and horseradish peroxidase isoenzyme C (HRPC) in the presence of large unilamellar vesicles of AOT (sodium bis-(2-ethylhexyl)sulfosuccinate) as templates at pH = 4.3 and <italic>T</italic> ~ 25 °C was investigated in a systematic way. In this cascade reaction mixture, the oxidation of aniline is catalyzed by HRPC with H2O2 that is formed in situ as byproduct of the GOD-catalyzed oxidation of <sc>d</sc>-glucose with O2. Under the elaborated experimental conditions which we considered ideal, the formation of PANI-ES products is evident, as judged by UV/Vis/NIR and EPR measurements. Comparison was made with a reference reaction, which was run under similar conditions with added H2O2 instead of GOD and <sc>d</sc>-glucose. Although the reference reaction was found to be superior, with the cascade reaction, PANI-ES products can still be obtained with high aniline conversion (&gt; 90%) within 24 h as stable dark green PANI-ES/AOT vesicle dispersion. Our results show that the in situ formation of H2O2 does not prevent the inactivation of HRPC known to occur in the reference reaction. Moreover, the GOD used in the cascade reaction is inactivated as well by polymerization intermediates.

  11. Growth and Division of Vesicles Coupled with Information Molecules

    Minoru KURISU, Masayuki IMAI, Peter WALDE

    Seibutsu Butsuri　61　(6)　378-381　2021

    Publisher: Biophysical Society of Japan

    DOI： 10.2142/biophys.61.378 　

    ISSN： 0582-4052

    eISSN： 1347-4219

  12. Vesicle deformation and division induced by flip-flop of lipid molecules

    Naohito Urakami, Yuka Sakuma, Toshikaze Chiba, Masayuki Imai

    Soft Matter　2021

    Publisher: Royal Society of Chemistry (RSC)

    DOI： 10.1039/d1sm00847a 　

    ISSN： 1744-683X

    eISSN： 1744-6848

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    We investigated the deformation of small unilamellar vesicles (SUVs) induced by flip-flops of lipids using coarse-grained molecular dynamics simulations. In case of single-component SUVs composed of zero spontaneous curvature lipids...

  13. NACore Amyloid Formation in the Presence of Phospholipids Peer-reviewed

    Jon Pallbo, Masayuki Imai, Luigi Gentile, Shin-ichi Takata, Ulf Olsson, Emma Sparr

    Frontiers in Physiology　11　2020/12/18

    DOI： 10.3389/fphys.2020.592117 　

    ISSN： 1664-042X

    eISSN： 1664-042X

  14. Morphologies of Vesicle Doublets: Competition among Bending Elasticity, Surface Tension, and Adhesion Peer-reviewed

    Kei Murakami, Ryuta Ebihara, Takuma Kono, Toshikaze Chiba, Yuka Sakuma, Primož Ziherl, Masayuki Imai

    Biophysical Journal　119　(9)　1735-1748　2020/11

    Publisher: Elsevier BV

    DOI： 10.1016/j.bpj.2020.09.030 　

    ISSN： 0006-3495

  15. Viscosity Landscape of Phase-Separated Lipid Membrane Estimated from Fluid Velocity Field Peer-reviewed

    Yuka Sakuma, Toshihiro Kawakatsu, Takashi Taniguchi, Masayuki Imai

    Biophysical Journal　2020/04

  16. Reproduction of vesicles coupled with a vesicle surface-confined enzymatic polymerisation Peer-reviewed

    Minoru Kurisu, Harutaka Aoki, Takehiro Jimbo, Yuka Sakuma, Masayuki Imai, Sandra Serrano-Luginbühl, Peter Walde

    communications chemistry　2　2019/11

    DOI： 10.1038/s42004-019-0218-0 　

  17. Hydrodynamic synchronization and collective dynamics of colloidal particles driven along a circular path Peer-reviewed

    Takumi Miyamoto, Masayuki Imai, Nariya Uchida

    Physical Review E　100　(3)　2019/09/11

    DOI： 10.1103/physreve.100.032607 　

    ISSN： 2470-0045

    eISSN： 2470-0053

  18. DNA length-dependent division of a giant vesicle-based model protocell Peer-reviewed

    M. Matsuo, Y. Kan, K. Kurihara, T. Jimbo, M. Imai, T. Toyota, Y. Hirata, K. Suzuki, T. Sugawara

    Sci. Rep.　9　6916 (1-11)　2019/05

  19. Construction of a chemical motor-movable frame assembly based on camphor grains using water-floating 3D-printed models Peer-reviewed

    H. Morohashi, M. Imai, T. Toyota

    Chemical Physics Letters　721　104-110　2019/02

  20. Migration of Deformable Vesicles Induced by Ionic Stimuli Peer-reviewed

    A. Kodama, M. Morandi, R. Ebihara, T. Jimbo, M. Toyoda, Y. Sakuma, M. Imai, N. Puff, M. I. Angelova

    Langmuir　34　11484-11494　2018/08

  21. Molecular mechanism of vesicle division induced by coupling between lipid geometry and membrane curvatures Peer-reviewed

    Naohito Urakami, Takehiro Jimbo, Yuka Sakuma, Masayuki Imai

    Soft Matter　14　(16)　3018-3027　2018

    Publisher: Royal Society of Chemistry

    DOI： 10.1039/c7sm02188g 　

    ISSN： 1744-6848 1744-683X

  22. Migration of Phospholipid Vesicles Can Be Selectively Driven by Concentration Gradients of Metal Chloride Solutions Peer-reviewed

    Atsuji Kodama, Yuka Sakuma, Masayuki Imai, Toshihiro Kawakatsu, Nicolas Puff, Miglena I. Angelova

    Langmuir　33　10698-10706　2017/09

  23. Role of Inverse-Cone-Shape Lipids in Temperature-Controlled Self-Reproduction of Binary Vesicles Peer-reviewed

    Takehiro Jimbo, Yuka Sakuma, Naohito Urakami, Primoz Ziherl, Masayuki Imai

    BIOPHYSICAL JOURNAL　110　(7)　1551-1562　2016/04

    DOI： 10.1016/j.bpj.2016.02.028 　

    ISSN： 0006-3495

    eISSN： 1542-0086

  24. 22aBW-8 Pore Formation on the Vesicle Induced by Chemical Stimuli

    Sakuma Y., Kodama A., Imai M.

    Meeting Abstracts of the Physical Society of Japan　71　3268-3268　2016

    Publisher: The Physical Society of Japan (JPS)

    DOI： 10.11316/jpsgaiyo.71.1.0_3268 　

    ISSN： 2189-079X

  25. 22aBW-11 Molecular Dynamics Simulation of Vesicle Division

    Urakami N., Imai M.

    Meeting Abstracts of the Physical Society of Japan　71　3271-3271　2016

    Publisher: The Physical Society of Japan (JPS)

    DOI： 10.11316/jpsgaiyo.71.1.0_3271 　

    ISSN： 2189-079X

  26. Migration of phospholipid vesicles in response to OH- stimuli Peer-reviewed

    Atsuji Kodama, Yuka Sakuma, Masayuki Imai, Yutaka Oya, Toshihiro Kawakatsu, Nicolas Puff, Miglena I. Angelova

    SOFT MATTER　12　(11)　2877-2886　2016

    DOI： 10.1039/c5sm02220g 　

    ISSN： 1744-683X

    eISSN： 1744-6848

  27. Molecular dynamics simulation for shape change of water-in-oil droplets Peer-reviewed

    Naohito Urakami, Akio Takaki, Masayuki Imai, Takashi Yamamoto

    MOLECULAR SIMULATION　41　(10-12)　986-992　2015/08

    DOI： 10.1080/08927022.2014.931582 　

    ISSN： 0892-7022

    eISSN： 1029-0435

  28. 18pCT-6 Migration of phospholipid vesicles in response to chemical stimuli

    Kodama A., Sakuma Y., Imai M., Oya Y., Kawakatsu T., Puff Nicolas, Angelova Miglena I.

    Meeting Abstracts of the Physical Society of Japan　70　2995-2995　2015

    Publisher: The Physical Society of Japan (JPS)

    DOI： 10.11316/jpsgaiyo.70.2.0_2995 　

    ISSN： 2189-079X

  29. 21pAQ-3 Response of Fatty Acid Vesicles to pH Stimuli

    Ikari K., Sakuma Y., Imai M., Monnard P.-A., Rasmussen S.

    Meeting Abstracts of the Physical Society of Japan　70　3264-3264　2015

    Publisher: The Physical Society of Japan (JPS)

    DOI： 10.11316/jpsgaiyo.70.1.0_3264 　

    ISSN： 2189-079X

  30. 24aAA-5 Self-propelling molecular aggregates of phospholipids

    Morohashi H., Toyota T., Imai M.

    Meeting Abstracts of the Physical Society of Japan　70　3407-3407　2015

    Publisher: The Physical Society of Japan (JPS)

    DOI： 10.11316/jpsgaiyo.70.1.0_3407 　

    ISSN： 2189-079X

  31. Shape transformations of toroidal vesicles Peer-reviewed

    Hiroshi Noguchi, Ai Sakashita, Masayuki Imai

    SOFT MATTER　11　(1)　193-201　2015

    DOI： 10.1039/c4sm01890g 　

    ISSN： 1744-683X

    eISSN： 1744-6848

  32. Dynamics of fatty acid vesicles in response to pH stimuli Peer-reviewed

    Keita Ikari, Yuka Sakuma, Takehiro Jimbo, Atsuji Kodama, Masayuki Imai, Pierre-Alain Monnard, Steen Rasmussen

    SOFT MATTER　11　(31)　6327-6334　2015

    DOI： 10.1039/c5sm01248a 　

    ISSN： 1744-683X

    eISSN： 1744-6848

  33. Morphological variation of a lipid vesicle confined in a spherical vesicle Peer-reviewed

    Ai Sakashita, Masayuki Imai, Hiroshi Noguchi

    PHYSICAL REVIEW E　89　(4)　040701® 1-4　2014/04

    DOI： 10.1103/PhysRevE.89.040701 　

    ISSN： 1539-3755

    eISSN： 1550-2376

  34. Dissipative Particle Dynamics Simulation for Vesicle Shape Change Peer-reviewed

    Yoshiyuki Oofuji, Naohito Urakami, Masayuki Imai, Takashi Yamamoto

    PROCEEDINGS OF INTERNATIONAL CONFERENCE ON ARTIFICIAL LIFE AND ROBOTICS (ICAROB 2014)　308-311　2014

  35. Tubular Membrane Formation of Binary Giant Unilamellar Vesicles Composed of Cylinder and Inverse-Cone-Shaped Lipids Peer-reviewed

    Yuka Sakuma, Takashi Taniguchi, Toshihiro Kawakatsu, Masayuki Imai

    BIOPHYSICAL JOURNAL　105　(9)　2074-2081　2013/11

    DOI： 10.1016/j.bpj.2013.09.021 　

    ISSN： 0006-3495

    eISSN： 1542-0086

  36. Slow Dynamics of Surfactant Micelles in Fluid and Crystal Phases Peer-reviewed

    M. Imai, M. Kurimoto, F. Matsuura, Y. Sakuma, T. Kawakatsu

    4TH INTERNATIONAL SYMPOSIUM ON SLOW DYNAMICS IN COMPLEX SYSTEMS: KEEP GOING TOHOKU　1518　758-765　2013

    DOI： 10.1063/1.4794675 　

    ISSN： 0094-243X

  37. 3PT142 Correlation between Membrane Composition and Mode of Division of PEG-grafted Giant Vesicles(The 50th Annual Meeting of the Biophysical Society of Japan)

    Kan Yumi, Kurihara Kensuke, Toyota Taro, Imai Masayuki, Sugawara Tadashi

    Seibutsu Butsuri　52　S165　2012

    Publisher: The Biophysical Society of Japan General Incorporated Association

    DOI： 10.2142/biophys.52.S165_3 　

  38. Hydrodynamic effects in multicomponent fluid membranes Invited

    S. Komura, S. Ramachandran, M. Imai

    Non-Equilibrium Soft Matter Physics　197-274　2012

  39. Dynamics of Heterogeneity in Fluid Membranes Peer-reviewed

    Shigeyuki Komura, Sanoop Ramachandran, Kazuhiko Seki, Masayuki Imai

    Advances in Planar Lipid Bilayers and Liposomes　16　129-164　2012

    DOI： 10.1016/B978-0-12-396534-9.00005-2 　

    ISSN： 1554-4516

  40. Lipid membrane deformation in response to a local pH modification: theory and experiments Peer-reviewed

    Anne-Florence Bitbol, Nicolas Puff, Yuka Sakuma, Masayuki Imai, Jean-Baptiste Fournier, Miglena I. Angelova

    SOFT MATTER　8　(22)　6073-6082　2012

    DOI： 10.1039/c2sm25519g 　

    ISSN： 1744-683X

  41. Three-dimensional analysis of lipid vesicle transformations Peer-reviewed

    Ai Sakashita, Naohito Urakami, Primoz Ziherl, Masayuki Imai

    SOFT MATTER　8　(33)　8569-8581　2012

    DOI： 10.1039/c2sm25759a 　

    ISSN： 1744-683X

  42. Diffusion of surfactant micelles in fluid and crystal phases Peer-reviewed

    M. Imai, M. Kurimoto, F. Matsuura, Y. Sakuma, T. Kawakatsu

    SOFT MATTER　8　(38)　9892-9905　2012

    DOI： 10.1039/c2sm07122c 　

    ISSN： 1744-683X

    eISSN： 1744-6848

  43. Model System of Self-Reproducing Vesicles Peer-reviewed

    Yuka Sakuma, Masayuki Imai

    PHYSICAL REVIEW LETTERS　107　(19)　198101　2011/10

    DOI： 10.1103/PhysRevLett.107.198101 　

    ISSN： 0031-9007

  44. Numerical investigations of the dynamics of two-component vesicles Peer-reviewed

    Takashi Taniguchi, Miho Yanagisawa, Masayuki Imai

    JOURNAL OF PHYSICS-CONDENSED MATTER　23　(28)　284103　2011/07

    DOI： 10.1088/0953-8984/23/28/284103 　

    ISSN： 0953-8984

  45. Asymmetric distribution of cone-shaped lipids in a highly curved bilayer revealed by a small angle neutron scattering technique Peer-reviewed

    Y. Sakuma, N. Urakami, T. Taniguchi, M. Imai

    JOURNAL OF PHYSICS-CONDENSED MATTER　23　(28)　2011/07

    DOI： 10.1088/0953-8984/23/28/284104 　

    ISSN： 0953-8984

  46. Hydrodynamic effects on concentration fluctuations in multicomponent membranes Peer-reviewed

    Sanoop Ramachandran, Shigeyuki Komura, Kazuhiko Seki, Masayuki Imai

    SOFT MATTER　7　(4)　1524-1531　2011

    DOI： 10.1039/c0sm00783h 　

    ISSN： 1744-683X

  47. Molecular dynamics simulation for morphological change of water-in-oil microemulsion droplets induced by addition of polymer chains Peer-reviewed

    Takahisa Kurokawa, Naohito Urakami, Kaori Nakaya Yaegashi, Ai Sakashita, Masayuki Imai, Takashi Yamamoto

    SOFT MATTER　7　(16)　7504-7510　2011

    DOI： 10.1039/c1sm05447c 　

    ISSN： 1744-683X

  48. Periodic modulation of tubular vesicles induced by phase separation Peer-reviewed

    Miho Yanagisawa, Masayuki Imai, Takashi Taniguchi

    PHYSICAL REVIEW E　82　(5)　051928　2010/11

    DOI： 10.1103/PhysRevE.82.051928 　

    ISSN： 1539-3755

    eISSN： 1550-2376

  49. Simulation of Shape Transformations of Lipid Bilayer Vesicles Peer-reviewed

    Iteru Noguchi, Naohito Urakami, Masayuki Imai, Takashi Yamamoto

    KOBUNSHI RONBUNSHU　67　(10)　605-610　2010/10

    ISSN： 0386-2186

  50. Pore Formation in a Binary Giant Vesicle Induced by Cone-Shaped Lipids Peer-reviewed

    Yuka Sakuma, Takashi Taniguchi, Masayuki Imai

    BIOPHYSICAL JOURNAL　99　(2)　472-479　2010/07

    DOI： 10.1016/j.bpj.2010.03.064 　

    ISSN： 0006-3495

  51. Order-Disorder Transition of Nonionic Onions under Shear Flow Peer-reviewed

    Yukiko Suganuma, Masayuki Imai, Tadashi Kato, Ulf Olsson, Tsutomu Takahashi

    LANGMUIR　26　(11)　7988-7995　2010/06

    DOI： 10.1021/la904862e 　

    ISSN： 0743-7463

  52. Drag coefficient of a liquid domain in a two-dimensional membrane Peer-reviewed

    S. Ramachandran, S. Komura, M. Imai, K. Seki

    EUROPEAN PHYSICAL JOURNAL E　31　(3)　303-310　2010/03

    DOI： 10.1140/epje/i2010-10577-3 　

    ISSN： 1292-8941

  53. Diffusion of domains on nanometer sized vesicle Peer-reviewed

    Y. Sakuma, N. Urakami, Y. Ogata, M. Nagao, S. Komura, T. Kawakatsu, M. Imai

    INTERNATIONAL CONFERENCE ON NEUTRON SCATTERING 2009　251　012036　2010

    DOI： 10.1088/1742-6596/251/1/012036 　

    ISSN： 1742-6588

  54. Shape deformation of giant vesicles encapsulating charged colloidal particles Peer-reviewed

    Yuno Natsume, Olivier Pravaz, Hirohisa Yoshida, Masayuki Imai

    SOFT MATTER　6　(21)　5359-5366　2010

    DOI： 10.1039/c0sm00396d 　

    ISSN： 1744-683X

    eISSN： 1744-6848

  55. Nonlinear Rheology of Surfactant Wormlike Micelles Bridged by Telechelic Polymers Peer-reviewed

    Herve Tabuteau, Laurence Ramos, Kaori Nakaya-Yaegashi, Masayuki Imai, Christian Ligoure

    LANGMUIR　25　(4)　2467-2472　2009/02

    DOI： 10.1021/la803304z 　

    ISSN： 0743-7463

  56. 3TA3-04 Periodic domain strucuture on ternary tubular veiscles(The 47th Annual Meeting of the Biophysical Society of Japan)

    Yanagisawa Miho, Imai Masayuki, Taniguchi Takashi

    Seibutsu Butsuri　49　S55　2009

    Publisher: The Biophysical Society of Japan General Incorporated Association

    DOI： 10.2142/biophys.49.S55_2 　

  57. Nano-meter-sized domain formation in lipid membranes observed by small angle neutron scattering Peer-reviewed

    T. Masui, N. Urakami, M. Imai

    EUROPEAN PHYSICAL JOURNAL E　27　(4)　379-389　2008/12

    DOI： 10.1140/epje/i2008-10400-x 　

    ISSN： 1292-8941

  58. Lamellar to micelle transition of nonionic surfactant assemblies induced by addition of colloidal particles Peer-reviewed

    Yukiko Suganuma, Naohito Urakami, Rina Mawatari, Shigeyuki Komura, Kaori Nakaya-Yaegashi, Masayuki Imai

    JOURNAL OF CHEMICAL PHYSICS　129　(13)　134903　2008/10

    DOI： 10.1063/1.2978385 　

    ISSN： 0021-9606

  59. Shape deformation of ternary vesicles coupled with phase separation Peer-reviewed

    Miho Yanagisawa, Masayuki Imai, Takashi Taniguchi

    PHYSICAL REVIEW LETTERS　100　(14)　148102　2008/04

    DOI： 10.1103/PhysRevLett.100.148102 　

    ISSN： 0031-9007

  60. Adhesion of binary giant vesicles containing negative spontaneous curvature lipids induced by phase separation Peer-reviewed

    Y. Sakuma, M. Imai, M. Yanagisawa, S. Komura

    EUROPEAN PHYSICAL JOURNAL E　25　(4)　403-413　2008/04

    DOI： 10.1140/epje/i2007-10307-0 　

    ISSN： 1292-8941

  61. 2S8-4 Shape deformation of ternary vesicles coupled with phase separation(2S8 Giant Liposome Research Front Line,The 46th Annual Meeting of the Biophysical Society of Japan)

    Yanagisawa Miho, Imai Masayuki, Taniguchi Takashi

    Seibutsu Butsuri　48　S13　2008

    Publisher: The Biophysical Society of Japan General Incorporated Association

    DOI： 10.2142/biophys.48.S13_4 　

    ISSN： 0582-4052

  62. Dynamics of nano-meter-sized domains on a vesicle Peer-reviewed

    Y. Sakuma, N. Urakami, Y. Ogata, M. Nagao, S. Komura, M. Imai

    COMPLEX SYSTEMS-BOOK 1　982　717-+　2008

    DOI： 10.1063/1.2897885 　

    ISSN： 0094-243X

  63. Shape deformation of vesicle coupled with phase separation Peer-reviewed

    Miho Yanagisawa, Masayuki Imai, Takashi Taniguchi

    Progress of Theoretical Physics Supplement　175　(175)　71-80　2008

    Publisher: Yukawa Institute for Theoretical Physics

    DOI： 10.1143/PTPS.175.71 　

    ISSN： 1347-4081 0375-9687

  64. Repulsive interlamellar interaction induced by addition of colloidal particles Peer-reviewed

    Yukiko Suganuma, Masayuki Imai, Kaori Nakaya

    JOURNAL OF APPLIED CRYSTALLOGRAPHY　40　S303-S306　2007/04

    DOI： 10.1107/S0021889807010345 　

    ISSN： 0021-8898

  65. Concentration fluctuations in binary fluid membranes Peer-reviewed

    K. Seki, S. Komura, M. Imai

    JOURNAL OF PHYSICS-CONDENSED MATTER　19　(7)　072101　2007/02

    DOI： 10.1088/0953-8984/19/7/072101 　

    ISSN： 0953-8984

  66. Growth dynamics of domains in ternary fluid vesicles Peer-reviewed

    Miho Yanagisawa, Masayuki Imai, Tomomi Masui, Shigeyuki Komura, Takao Ohta

    BIOPHYSICAL JOURNAL　92　(1)　115-125　2007/01

    DOI： 10.1529/biophysj.106.087494 　

    ISSN： 0006-3495

  67. Microdomain formation in model biomembranes Peer-reviewed

    Tomomi Masui, Masayuki Imai, Naohito Urakami

    PHYSICA B-CONDENSED MATTER　385　821-823　2006/11

    DOI： 10.1016/j.physb.2006.06.099 　

    ISSN： 0921-4526

  68. Polymer crystallization from the metastable melt: The formation mechanism of spherulites Peer-reviewed

    Masayuki Imai, Keisuke Kaji

    POLYMER　47　(15)　5544-5554　2006/07

    DOI： 10.1016/j.polymer.2005.07.109 　

    ISSN： 0032-3861

    eISSN： 1873-2291

  69. Effects of grafted polymer chains on lamellar membranes Peer-reviewed

    T Masui, M Imai, K Nakaya, T Taniguchi

    JOURNAL OF CHEMICAL PHYSICS　124　(7)　074904 (1-12)　2006/02

    DOI： 10.1063/1.2168452 　

    ISSN： 0021-9606

  70. 〈繊維関連分野における自己組織化現象〉高分子の結晶化素過程と自己組織化

    梶 慶輔, 西田 幸次, 金谷 利治, 松葉 豪, 小西 隆, 今井 正幸

    繊維学会誌　62　(4)　P.88-P.92　2006

    Publisher: The Society of Fiber Science and Technology, Japan

    DOI： 10.2115/fiber.62.P_88 　

    ISSN： 0037-9875

  71. Surfactant mesophases mediated by colloidal particles Peer-reviewed

    M Imai, Y Suganuma, K Nakaya, S Komura

    JOURNAL OF PHYSICS-CONDENSED MATTER　17　(31)　S2929-S2935　2005/08

    DOI： 10.1088/0953-8984/17/31/020 　

    ISSN： 0953-8984

  72. Shear-induced structural transition in a lyotropic lamellar phase studied using small angle neutron and light scattering Peer-reviewed

    T Kato, K Miyazaki, Y Kawabata, S Komura, M Fujii, M Imai

    JOURNAL OF PHYSICS-CONDENSED MATTER　17　(31)　S2923-S2928　2005/08

    DOI： 10.1088/0953-8984/17/31/019 　

    ISSN： 0953-8984

  73. Polymer-confinement-induced nematic transition of microemulsion droplets Peer-reviewed

    K Nakaya, M Imai, S Komura, T Kawakatsu, N Urakami

    EUROPHYSICS LETTERS　71　(3)　494-500　2005/08

    DOI： 10.1209/epl/i2005-10093-3 　

    ISSN： 0295-5075

  74. Kinetic pathway to double-gyroid structure Peer-reviewed

    M Imai, K Sakai, M Kikuchi, K Nakaya, A Saeki, T Teramoto

    JOURNAL OF CHEMICAL PHYSICS　122　(21)　214906 (1-10)　2005/06

    DOI： 10.1063/1.1905585 　

    ISSN： 0021-9606

    eISSN： 1089-7690

  75. Effects of grafted amphiphilic triblockcopolymers on the higher-order structures

    Tomomi Masui, Masayuki Imai, Kaori Nakaya

    Polymer Preprints, Japan　54　(1)　1142　2005

  76. Micro-domain growth in lipid membranes

    Masayuki Imai, Tomomi Masui, Miho Yanagisawa

    Polymer Preprints, Japan　54　(2)　3954-3955　2005

  77. Static and dynamic structures of spherical nonionic surfactant micelles during the disorder-order transition Peer-reviewed

    M Imai, Yoshida, I, T Iwaki, K Nakaya

    JOURNAL OF CHEMICAL PHYSICS　122　(4)　044906 (1-9)　2005/01

    DOI： 10.1063/1.1839559 　

    ISSN： 0021-9606

    eISSN： 1089-7690

  78. Spinodal crystallization of polymers: Crystallization from the unstable melt Peer-reviewed

    K Kaji, K Nishida, T Kanaya, G Matsuba, T Konishi, M Imai

    INTERPHASES AND MESOPHASES IN POLYMER CRYSTALLIZATION III　191　187-240　2005

    DOI： 10.1007/12_013 　

    ISSN： 0065-3195

  79. Anomalous decrease in lamellar spacing by shear flow in a nonionic surfactant/water system Peer-reviewed

    T Kato, K Minewaki, Y Kawabata, M Imai, Y Takahashi

    LANGMUIR　20　(9)　3504-3508　2004/04

    DOI： 10.1021/la0361058 　

    ISSN： 0743-7463

  80. Inter-lamellar interactions modulated by addition of guest components Peer-reviewed

    M Imai, R Mawatari, K Nakaya, S Komura

    EUROPEAN PHYSICAL JOURNAL E　13　(4)　391-400　2004/04

    DOI： 10.1140/epje/i2003-10085-7 　

    ISSN： 1292-8941

  81. Anomalous change in lamellar spacing by shear flow in nonionic surfactant/water system Peer-reviewed

    T Kato, K Minewaki, K Miyazaki, Y Kawabata, M Imai

    SLOW DYNAMICS IN COMPLEX SYSTEMS　708　94-95　2004

    ISSN： 0094-243X

  82. Morphology transition from sphere to rod by confining the polymer chains in a dilute microemulsion system Peer-reviewed

    K Nakaya, M Imai, S Komura, N Urakami

    SLOW DYNAMICS IN COMPLEX SYSTEMS　708　106-107　2004

    ISSN： 0094-243X

  83. Inter-lamellar interaction mediated by amphiphilic triblock copolymer Peer-reviewed

    T Masui, M Imai, K Nakaya

    SLOW DYNAMICS IN COMPLEX SYSTEMS　708　108-109　2004

    ISSN： 0094-243X

  84. Fluctuation modes prior to lamellar-double gyroid transition of a nonionic surfactant/water system Peer-reviewed

    M Imai, K Nakaya, T Kawakatsu

    SLOW DYNAMICS IN COMPLEX SYSTEMS　708　114-115　2004

    ISSN： 0094-243X

  85. Dynamical nature of least stable fluctuation modes of lamellar structure observed in a nonionic surfactant/water system Peer-reviewed

    M Imai, K Nakaya, T Kawakatsu, H Seto

    JOURNAL OF CHEMICAL PHYSICS　119　(15)　8103-8111　2003/10

    DOI： 10.1063/1.1606434 　

    ISSN： 0021-9606

  86. Effects of guest hydrophobic molecule on stability of ordered meso structure of a surfactant/water system Peer-reviewed

    M Imai, T Teramoto, Takahashi, I, Y Nishiura

    JOURNAL OF CHEMICAL PHYSICS　119　(7)　3891-3895　2003/08

    DOI： 10.1063/1.1591734 　

    ISSN： 0021-9606

  87. Dependence on sphere size of the phase behavior of mixtures of rods and spheres Peer-reviewed

    N Urakami, M Imai

    JOURNAL OF CHEMICAL PHYSICS　119　(4)　2463-2470　2003/07

    DOI： 10.1063/1.1585025 　

    ISSN： 0021-9606

  88. The effect of sphere size on the phase behaviors in the rod and sphere mixture system Peer-reviewed

    N Urakami, M Imai

    JOURNAL OF MACROMOLECULAR SCIENCE-PHYSICS　B42　(3-4)　533-543　2003

    DOI： 10.1081/MB-120021580 　

    ISSN： 0022-2348

  89. Details of structure formation during the induction period of spinodal-type polymer crystallization Peer-reviewed

    K Kaji, K Nishida, G Matsuba, T Kanaya, M Imai

    JOURNAL OF MACROMOLECULAR SCIENCE-PHYSICS　B42　(3-4)　709-715　2003

    DOI： 10.1081/MB-120021601 　

    ISSN： 0022-2348

  90. Polysaccharides induced crystallization of tobacco mosaic virus particles Peer-reviewed

    M Imai, N Urakami, A Nakamura, R Takada, R Oikawa, Y Sano

    LANGMUIR　18　(25)　9918-9923　2002/12

    DOI： 10.1021/la0204747 　

    ISSN： 0743-7463

  91. Kinetic pathway of lamellar -&gt; gyroid transition: Pretransition and transient states Peer-reviewed

    M Imai, A Saeki, T Teramoto, A Kawaguchi, K Nakaya, T Kato, K Ito

    JOURNAL OF CHEMICAL PHYSICS　115　(22)　10525-10531　2001/12

    ISSN： 0021-9606

  92. Shear-induced ordering of lamellar and gyroid structures observed in a nonionic surfactant/water system Peer-reviewed

    R Imai, K Nakaya, T Kato

    EUROPEAN PHYSICAL JOURNAL E　5　(4)　391-402　2001/07

    ISSN： 1292-8941

  93. Small-angle X-ray scattering from the lamellar phase formed in a nonionic surfactant (C16E7)-Water system. Analysis of peak position and line shape Peer-reviewed

    K Minewaki, T Kato, H Yoshida, M Imai, K Ito

    LANGMUIR　17　(6)　1864-1871　2001/03

    DOI： 10.1021/la000791i 　

    ISSN： 0743-7463

  94. Effects of shear flow on the structure of the lamellar phase formed in nonionic surfactant-water system

    K. Minewaki, T. Kato, M. Imai

    Studies in Surface Science and Catalysis　132　185-188　2001

    Publisher: Elsevier Inc.

    DOI： 10.1016/s0167-2991(01)82065-6 　

    ISSN： 0167-2991

  95. Kinetics of Lamellar to Gyroid Transition in a Nonionic Surfactant System

    M. Imai, A. Kawaguchi, A. Saeki, K. Nakaya, T. Kato, K. Ito

    Studies in Surface Science and Catalysis　132　35-38　2001

    Publisher: Elsevier Inc.

    DOI： 10.1016/s0167-2991(01)82031-0 　

    ISSN： 0167-2991

  96. Scattering Study of the Lyotropic Lamellar Phase in Aqueous Solutions of Nonionic Surfactants

    Tadashi Kato, Koji Minewaki, Hirohisa Yoshida, Masayuki Imai, Kazuki Ito

    Studies in Surface Science and Catalysis　25-30　2001

    Publisher: Elsevier

    DOI： 10.1016/s0167-2991(01)82029-2 　

    ISSN： 0167-2991

  97. Fluctuations of lamellar structure prior to a lamellar -&gt; gyroid transition in a nonionic surfactant system Peer-reviewed

    M Imai, A Kawaguchi, A Saeki, K Nakaya, T Kato, K Ito, Y Amemiya

    PHYSICAL REVIEW E　62　(5)　6865-6874　2000/11

    ISSN： 1063-651X

  98. Apparatus for small-angle neutron scattering and rheological measurements under sheared conditions Peer-reviewed

    Y Takahashi, M Noda, M Naruse, T Kanaya, H Watanabe, T Kato, M Imai, Y Matsushita

    NIHON REOROJI GAKKAISHI　28　(4)　187-191　2000

    ISSN： 0387-1533

  99. The effects of chondroitin sulfate on the tobacco mosaic virus configuration Peer-reviewed

    N Urakami, M Imai, Y Sano, M Takasu

    PROGRESS OF THEORETICAL PHYSICS SUPPLEMENT　138　(138)　390-391　2000

    ISSN： 0375-9687

  100. Conformational change and orientation fluctuations prior to the crystallization of syndiotactic polystyrene Peer-reviewed

    G Matsuba, K Kaji, K Nishida, T Kanaya, M Imai

    MACROMOLECULES　32　(26)　8932-8937　1999/12

    ISSN： 0024-9297

  101. Shear effects on the morphology transition in a nonionic surfactant system Peer-reviewed

    M Imai, K Nakaya, T Kato, Y Takahashi, T Kanaya

    JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS　60　(8-9)　1313-1319　1999/08

    ISSN： 0022-3697

    eISSN： 1879-2553

  102. The isotropic-nematic transition and the phase separation of the tobacco mosaic virus particles with polysaccharide Peer-reviewed

    N Urakami, M Imai, Y Sano, M Takasu

    JOURNAL OF CHEMICAL PHYSICS　111　(5)　2322-2328　1999/08

    ISSN： 0021-9606

  103. Small-angle neutron scattering studies on phase behavior of block copolymers Peer-reviewed

    H Hasegawa, N Sakamoto, H Takeno, H Jinnai, T Hashimoto, D Schwahn, H Frielinghaus, S Janssen, M Imai, K Mortensen

    JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS　60　(8-9)　1307-1312　1999/08

    ISSN： 0022-3697

  104. Collective motions of a network of wormlike micelles Peer-reviewed

    H Seto, T Kato, M Monkenbusch, T Takeda, Y Kawabata, M Nagao, D Okuhara, M Imai, S Komura

    JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS　60　(8-9)　1371-1373　1999/08

    ISSN： 0022-3697

  105. Elasticity effects on domain coarsening of the lamellar-gyroid transition observed in a nonionic surfactant system Peer-reviewed

    M Imai, K Nakaya, T Kato

    PHYSICAL REVIEW E　60　(1)　734-739　1999/07

    ISSN： 1063-651X

  106. Concentration dependence of radius of gyration of sodium poly(styrenesulfonate) over a wide range of concentration studied by small-angle neutron scattering Peer-reviewed

    Y Takahashi, N Matsumoto, S Iio, H Kondo, Noda, I, M Imai, Y Matsushita

    LANGMUIR　15　(12)　4120-4122　1999/06

    ISSN： 0743-7463

  107. Analytical solutions describing the phase separation driven by a free energy functional containing a long-range interaction term Peer-reviewed

    Ohnishi, I, Y Nishiura, M Imai, Y Matsushita

    CHAOS　9　(2)　329-341　1999/06

    DOI： 10.1063/1.166410 　

    ISSN： 1054-1500

  108. Tip-splitting crystal growth observed in crystallization from thin films of poly(ethylene terephthalate) Peer-reviewed

    Y Sakai, M Imai, K Kaji, M Tsuji

    JOURNAL OF CRYSTAL GROWTH　203　(1-2)　244-254　1999/05

    ISSN： 0022-0248

    eISSN： 1873-5002

  109. Structure of a lamellar phase formed by non-ionic surfactant and water

    K. Minewaki, T. Kato, H. Yoshida, M. Imai

    Journal of Thermal Analysis and Calorimetry　57　(3)　753-758　1999

    Publisher: Kluwer Academic Publishers

    ISSN： 1388-6150

  110. Spatial Distribution of Chain Stems and Chain Folding Mode in Polyethylene Lamellae as Revealed by Coupled Information of DSC, FT-IR, SANS, and WANS.

    Sasaki Sono, Tashiro Kohji, Gose Naomi, Imanishi Kouji, Izuchi Masaaki, Kobayashi Masamichi, Imai Masayuki, Ohashi Masayoshi, Yamaguchi Yasuo, Ohoyama Kenji

    Polymer Journal　31　(8)　677-686　1999

    Publisher: The Society of Polymer Science, Japan

    DOI： 10.1295/polymj.31.677 　

    ISSN： 0032-3896

    More details Close

    Aggregation structure of polyethylene (PE) chains in the crystalline state as well as in the molten state was investigated by an organized combination of the small-angle neutron scattering, infrared spectra and thermal analysis. The used samples were the blends between the deuterated and hydrogeneous PE (and n-alkane), which were cocrystallized almost perfectly into the common lamella even when they were cooled slowly from the melt. The quantitative analysis of the small-angle neutron scattering data showed that the D and H species were homogeneously mixed in the melt and the radius of gyration of a chain was kept unchanged even when the chains were enrolled together into the crystalline lamellae. On the basis of the quantitative analysis of infrared spectra, the chain stems included in the crystalline lamella were found to be gathered together in a statistically random fashion. This structural idea could be also used reasonably to interpret the dependence of the melting point on the D/H content. From all these data it was concluded that the chain folding in the PE lamella occurs in a statistically random reentry mode even for the PE samples crystallized slowly from the melt under the normal condition.

  111. Slow dynamics of morphology transition observed in a surfactant system Peer-reviewed

    M Imai, K Nakaya, T Kato, K Ito, Y Amemiya, D Schneider

    SLOW DYNAMICS IN COMPLEX SYSTEMS　469　142-143　1999

    ISSN： 0094-243X

  112. Conformational change and orientation fluctuations of isotactic polystyrene prior to crystallization Peer-reviewed

    G Matsuba, K Kaji, K Nishida, T Kanaya, M Imai

    POLYMER JOURNAL　31　(9)　722-727　1999

    ISSN： 0032-3896

  113. Isothermal crystallisation of end-linked poly(tetrahydrofuran) networks. 3. Small-angle neutron scattering

    Mitsuhiro Shibayama, Hiroshi Takahashi, Shunji Nomura, Masayuki Imai

    Polymer　39　(16)　3759-3766　1998/06/01

    Publisher: Elsevier BV

    DOI： 10.1016/S0032-3861(97)10145-8 　

    ISSN： 0032-3861

  114. Small-angle neutron scattering study on charged gels in deformed state Peer-reviewed

    M Shibayama, K Kawakubo, F Ikkai, M Imai

    MACROMOLECULES　31　(8)　2586-2592　1998/04

    ISSN： 0024-9297

  115. Small-angle X-ray and neutron scattering from dilute solutions of cesium perfluorooctanoate. Micellar growth along two dimensions Peer-reviewed

    H Iijima, T Kato, H Yoshida, M Imai

    JOURNAL OF PHYSICAL CHEMISTRY B　102　(6)　990-995　1998/02

    ISSN： 1520-6106

  116. Small-Angle X-ray and Neutron Scattering from Dilute Solutions of Cesium Perfluorooctanoate. Micellar Growth along Two Dimensions. Peer-reviewed

    IIJIMA H, YOSHIDA H, KATO T, IMAI M

    J. Phys. Chem. B　102　(6)　990-995　1998

    DOI： 10.1021/jp973048g 　

    ISSN： 1089-5647

  117. Order-disorder transition of symmetric poly(styrene-b-2-vinylpyridine) in bulk and solution Peer-reviewed

    Y Takahashi, S Kitade, M Noda, N Ochiai, Noda, I, M Imai, Y Matsushita

    POLYMER JOURNAL　30　(5)　388-393　1998

    ISSN： 0032-3896

    eISSN： 1349-0540

  118. Coarsening of cubic lattice domains observed in a nonionic surfactant system Peer-reviewed

    M Imai, T Kato, D Schneider

    JOURNAL OF CHEMICAL PHYSICS　108　(4)　1710-1714　1998/01

    ISSN： 0021-9606

  119. Solvent contrast variation study of w/o AOT microemulsions using small-angle neutron scattering Peer-reviewed

    R Kawai-Hirai, M Hirai, H Iwase, S Arai, M Imai, Y Matsushita

    PHYSICA B　241　984-986　1997/12

    ISSN： 0921-4526

  120. Structural evolution and microscopic interactions in a three-component amphiphilic microemulsion system Peer-reviewed

    S. Komura, H. Seto, T. Takeda, M. Nagao, Y. Ito, M. Imai

    J. Chem. Phys.　106　64-69　1997/08

  121. Small-Angle Neutron Scattering Study of Metallic Sodium on Phase Transition Peer-reviewed

    H. Abe, R. J. Matsuo, M. Ishibashi, K. Ohshima, M. Imai, K. Kakurai

    J. Phys. Soc. Jpn　66　(7)　508-511　1997/07

    Publisher: The Physical Society of Japan (JPS)

    DOI： 10.1143/JPSJ.66.1860 　

    ISSN： 0031-9015

    More details Close

    In metallic sodium, a characteristic waiting time, which is the incubation time until phase transition starts, appears above M s at a fixed temperature. Small-angle neutron scattering from clusters of the low-temperature phase is observed, which shows good agreement with the aggregation-of-spheres model, whose radius distribution is a Maxwell distribution function. Using the aggregation-of-spheres model, the average radius, r0, of clusters of the low-temperature phase was found to be 57.2 &Aring;. Moreover, abnormal small-angle neutron scattering from local fluctuations is seen during the waiting time, where this waiting time is related to the nucleation process in the martensitic phase transition.

  122. Fluctuations and growth of a cubic network observed in a nonionic surfactant system Peer-reviewed

    M Imai, T Kato, D Schneider

    JOURNAL OF CHEMICAL PHYSICS　106　(22)　9362-9371　1997/06

    ISSN： 0021-9606

  123. A small-angle neutron scattering study on the small aggregates of bacteriochlorophylls in solutions Peer-reviewed

    ZY Wang, M Umetsu, K Yoza, M Kobayashi, M Imai, Y Matsushita, N Niimura, T Nozawa

    BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS　1320　(1)　73-82　1997/05

    ISSN： 0005-2728

  124. Neutron scattering study of phosphatidylinositol 4,5-bis(phosphate) aqueous dispersion Peer-reviewed

    M Hirai, S Yabuki, T Takizawa, K Hayashi, M Imai, Y Matsushita, Y Ito

    FORMATION AND DYNAMICS OF SELF-ORGANIZED STRUCTURES IN SURFACTANTS AND POLYMER SOLUTIONS　106　232-236　1997

    ISSN： 0340-255X

  125. Fluctuations of cubic network observed in non-ionic surfactant system Peer-reviewed

    M Imai, T Kato, D Schneider

    FORMATION AND DYNAMICS OF SELF-ORGANIZED STRUCTURES IN SURFACTANTS AND POLYMER SOLUTIONS　106　64-69　1997

    ISSN： 0340-255X

  126. Structure functions and interfacial mean curvatures in a ternary amphiphilic system C12E5/water/n-octane Peer-reviewed

    SK Ghosh, S Komura, H Seto, J Matsuba, T Takeda, M Kokosaka, M Imai

    FORMATION AND DYNAMICS OF SELF-ORGANIZED STRUCTURES IN SURFACTANTS AND POLYMER SOLUTIONS　106　98-103　1997

    ISSN： 0340-255X

  127. High pressure cell for small-angle neutron and light scattering studies of phase transitions in complex liquids Peer-reviewed

    H Takeno, M Nagao, Y Nakayama, H Hasegawa, T Hashimoto, H Seto, M Imai

    POLYMER JOURNAL　29　(11)　931-939　1997

    ISSN： 0032-3896

  128. Isothermal evolution of long range order in bulk metallic glass Ni15Pt60P25 near glass transition: In-situ SANS measurement Peer-reviewed

    K Shibata, T Higuchi, AP Tsai, M Imai, K Suzuki

    PROGRESS OF THEORETICAL PHYSICS SUPPLEMENT　126　(126)　75-78　1997

    ISSN： 0375-9687

  129. Structure functions and interfacial mean curvatures in a ternary amphiphilic system C12E5/water/n-octane Peer-reviewed

    S.K. Ghosh, S. Komura, H. Seto, J. Matsuba, T. Takeda, M. Hikosaka, M. Imai

    Progr Colloid Polym. Sci.　106　223-227　1997

  130. Neutron scattering study of phosphatidylinositol 4,5-bis(phosphate) aqueous dispersion Peer-reviewed

    M. Hirai, T. Takizawa, K. Hayashi, S. Yabuki, M. Imai, Y. Matsushita, Y. Ito

    Progress in Colloid and Polymer Science　106　232-236　1997

    Publisher: Springer Verlag

    DOI： 10.1007/BF01189527 　

    ISSN： 0340-255X

  131. Micellar growth in dilute solutions of cesium perfluorooctanoate studied by small angle X-ray and neutron scattering Peer-reviewed

    H Iijima, T Kato, T Seimiya, H Yoshida, M Imai

    FORMATION AND DYNAMICS OF SELF-ORGANIZED STRUCTURES IN SURFACTANTS AND POLYMER SOLUTIONS　106　61-63　1997

    ISSN： 0340-255X

  132. Crossover from mean field to three-dimensional Ising critical behavior in a three-component microemulsion system Peer-reviewed

    Seto H, Schwahn D, Nagao M, Yokoi E, Komura S, Imai M, Mortensen K

    Physical Review E - Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics　54　(1)　629-633　1996/12/01

    DOI： 10.1103/PhysRevE.54.629 　

    ISSN： 1063-651X

  133. Growth shape observed in two-dimensional poly(ethylene terephthalate) spherulites Peer-reviewed

    Y Sakai, M Imai, K Kaji, M Tsuji

    MACROMOLECULES　29　(27)　8830-8834　1996/12

    ISSN： 0024-9297

    eISSN： 1520-5835

  134. Change of distribution of free volume holes during crystallization of poly(ethylene terephthalate) revealed by positron annihilation lifetime spectroscopy Peer-reviewed

    HFM Mohamed, YS Ito, M Imai

    JOURNAL OF CHEMICAL PHYSICS　105　(11)　4841-4845　1996/09

    ISSN： 0021-9606

    eISSN： 1089-7690

  135. Structural evolution and microscopic interactions in a three-component amphiphilic microemulsion system Peer-reviewed

    S Komura, H Seto, T Takeda, M Nagao, YJ Ito, M Imai

    JOURNAL OF CHEMICAL PHYSICS　105　(8)　3264-3277　1996/08

    DOI： 10.1063/1.471842 　

    ISSN： 0021-9606

  136. Low-energy excitations of amorphous and semicrystalline poly(ethylene terephthalate)s Peer-reviewed

    T Kanaya, M Imai, K Kaji

    PHYSICA B　226　(1-3)　82-85　1996/08

    ISSN： 0921-4526

  137. Crossover from mean field to three-dimensional Ising critical behavior in a three-component microemulsion system Peer-reviewed

    H Seto, D Schwahn, M Nagao, E Yokoi, S Komura, M Imai, K Mortensen

    PHYSICAL REVIEW E　54　(1)　629-633　1996/07

    ISSN： 1539-3755

  138. COCRYSTALLIZATION AND PHASE SEGREGATION OF POLYETHYLENE BLENDS BETWEEN THE D-SPECIES AND H-SPECIES .8. SMALL-ANGLE NEUTRON-SCATTERING STUDY OF THE MOLTEN STATE AND THE STRUCTURAL RELATIONSHIP OF CHAINS BETWEEN THE MELT AND THE CRYSTALLINE STATE Peer-reviewed

    K TASHIRO, K IMANISHI, M IZUCHI, M KOBAYASHI, Y ITOH, M IMAI, Y YAMAGUCHI, M OHASHI, RS STEIN

    MACROMOLECULES　28　(25)　8484-8490　1995/12

    ISSN： 0024-9297

  139. PERIPHERALLY BIASED DISTRIBUTION OF ANTIGEN PROTEINS ON THE RECOMBINANT YEAST-DERIVED HUMAN HEPATITIS-B VIRUS SURFACE-ANTIGEN VACCINE PARTICLE - STRUCTURAL CHARACTERISTICS REVEALED BY SMALL-ANGLE NEUTRON-SCATTERING USING THE CONTRAST VARIATION METHOD Peer-reviewed

    M SATO, Y SATOMIYAMOTO, K KAMEYAMA, N ISHIKAWA, M IMAI, Y ITO, T TAKAGI

    JOURNAL OF BIOCHEMISTRY　118　(6)　1297-1302　1995/12

    ISSN： 0021-924X

  140. ORDERING PROCESS IN THE INDUCTION PERIOD OF CRYSTALLIZATION OF POLY(ETHYLENE-TEREPHTHALATE) Peer-reviewed

    M IMAI, K KAJI, T KANAYA, Y SAKAI

    PHYSICAL REVIEW B　52　(17)　12696-12704　1995/11

    ISSN： 0163-1829

  141. EFFECTS OF POLYMER ADSORPTION ON STRUCTURES AND RHEOLOGY OF COLLOIDAL SILICA SUSPENSIONS Peer-reviewed

    M KAWAGUCHI, R NAKA, M IMAI, T KATO

    LANGMUIR　11　(11)　4323-4327　1995/11

    ISSN： 0743-7463

  142. STRUCTURAL ORDERING ON PHYSICAL GELATION OF SYNDIOTACTIC POLYSTYRENE DISPERSED IN CHLOROFORM STUDIED BY TIME-RESOLVED MEASUREMENTS OF SMALL-ANGLE NEUTRON-SCATTERING (SANS) AND INFRARED-SPECTROSCOPY Peer-reviewed

    M KOBAYASHI, T YOSHIOKA, M IMAI, Y ITOH

    MACROMOLECULES　28　(22)　7376-7385　1995/10

    ISSN： 0024-9297

  143. LAMELLAR MICROPHASE-SEPARATED STRUCTURE OF ABA TRIBLOCK COPOLYMERS Peer-reviewed

    Y MATSUSHITA, M NOMURA, NODA, I, M IMAI

    PHYSICA B　213　697-699　1995/08

    ISSN： 0921-4526

  144. SMALL-ANGLE NEUTRON-SCATTERING STUDY OF RECOMBINANT YEAST-DERIVED HUMAN HEPATITIS-B VIRUS SURFACE-ANTIGEN VACCINE PARTICLE Peer-reviewed

    M SATO, Y ITO, K KAMEYAMA, M IMAI, N ISHIKAWA, T TAKAGI

    PHYSICA B　213　757-759　1995/08

    ISSN： 0921-4526

  145. CRITICAL CROSSOVER PHENOMENA IN COMPATIBLE POLYMER BLENDS STUDIED WITH SANS Peer-reviewed

    D SCHWAHN, S JANSSEN, L WILLNER, T SCHMACKERS, T SPRINGER, K MORTENSEN, H TAKENO, H HASEGAWA, H JINNAI, T HASHIMOTO, M IMAI

    PHYSICA B-CONDENSED MATTER　213　685-687　1995/08

    ISSN： 0921-4526

  146. DYNAMICAL ASPECT OF PHYSICAL GELATION OF SYNDIOTACTIC POLYSTYRENE REVEALED BY TIME-RESOLVED SANS Peer-reviewed

    M KOBAYASHI, T YOSHIOKA, M IMAI, Y ITOH

    PHYSICA B　213　734-736　1995/08

    ISSN： 0921-4526

  147. "The Crossover from Meanfield to 3D-Ising Critical Behavior in a 3-Component Microemulsion. "

    H. Seto, D. Schwahn, E. Yokoi, M. Nagao, S. Komura, M. Imai, K. Mortensen

    Physica B　213-214　591-593　1995/08/01

    DOI： 10.1016/0921-4526(95)00221-T 　

    ISSN： 0921-4526

  148. CHAIN CONFORMATION IN THE INDUCTION PERIOD OF CRYSTALLIZATION OF POLY(ETHYLENE-TEREPHTHALATE) Peer-reviewed

    M IMAI, K KAJI, T KANAYA, Y SAKAI

    PHYSICA B　213　718-720　1995/08

    ISSN： 0921-4526

  149. SMALL-ANGLE NEUTRON-SCATTERING INSTRUMENT OF THE INSTITUTE FOR SOLID-STATE PHYSICS, UNIVERSITY-OF-TOKYO (SANS-U) Peer-reviewed

    Y ITO, M IMAI, S TAKAHASHI

    PHYSICA B　213　889-891　1995/08

    ISSN： 0921-4526

  150. ALTERNATING LAMELLAR STRUCTURE OF TRIBLOCK COPOLYMERS OF THE ABA TYPE Peer-reviewed

    Y MATSUSHITA, M NOMURA, J WATANABE, Y MOGI, NODA, I, M IMAI

    MACROMOLECULES　28　(18)　6007-6013　1995/08

    ISSN： 0024-9297

  151. STUDY ON LOCAL MAGNETIC-FLUX DISTRIBUTION IN TYPE-II SUPERCONDUCTORS BY MEANS OF SMALL-ANGLE NEUTRON-SCATTERING Peer-reviewed

    K OSAMURA, H OKUDA, M FURUSAKA, Y ITOH, M IMAI, T MATSUSHITA, ES OTABE

    IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY　5　(2)　1810-1813　1995/06

    ISSN： 1051-8223

  152. MICROSTRUCTURAL EFFECTS ON THE GINZBURG NUMBER AND THE CROSSOVER-BEHAVIOR IN D-PB/PS BLENDS Peer-reviewed

    D SCHWAHN, H TAKENO, L WILLNER, H HASEGAWA, H JINNAI, T HASHIMOTO, M IMAI

    PHYSICAL REVIEW LETTERS　73　(25)　3427-3430　1994/12

    ISSN： 0031-9007

  153. STRUCTURAL FORMATION OF POLY(ETHYLENE-TEREPHTHALATE) DURING THE INDUCTION PERIOD OF CRYSTALLIZATION .3. EVOLUTION OF DENSITY-FLUCTUATIONS TO LAMELLAR CRYSTAL Peer-reviewed

    M IMAI, K KAJI, T KANAYA

    MACROMOLECULES　27　(24)　7103-7108　1994/11

    ISSN： 0024-9297

  154. ORIENTATION FLUCTUATIONS OF POLY(ETHYLENE-TEREPHTHALATE) DURING THE INDUCTION PERIOD OF CRYSTALLIZATION Peer-reviewed

    M IMAI, K KAJI, T KANAYA

    PHYSICAL REVIEW LETTERS　71　(25)　4162-4165　1993/12

    ISSN： 0031-9007

  155. STRUCTURE FORMATION OF POLY(ETHYLENE-TEREPHTHALATE) DURING ANNEALING PROCESS Peer-reviewed

    M IMAI, T MIZUKAMI, T KANAYA, K KAJI

    SLOW DYNAMICS IN CONDENSED MATTER　256　230-231　1992

  156. STRUCTURAL FORMATION OF POLY(ETHYLENE-TEREPHTHALATE) DURING THE INDUCTION PERIOD OF CRYSTALLIZATION .1. ORDERED STRUCTURE APPEARING BEFORE CRYSTAL NUCLEATION Peer-reviewed

    M IMAI, K MORI, T MIZUKAMI, K KAJI, T KANAYA

    POLYMER　33　(21)　4451-4456　1992

    ISSN： 0032-3861

  157. STRUCTURAL FORMATION OF POLY(ETHYLENE-TEREPHTHALATE) DURING THE INDUCTION PERIOD OF CRYSTALLIZATION .2. KINETIC-ANALYSIS BASED ON THE THEORIES OF PHASE-SEPARATION Peer-reviewed

    M IMAI, K MORI, T MIZUKAMI, K KAJI, T KANAYA

    POLYMER　33　(21)　4457-4462　1992

    ISSN： 0032-3861

  158. SERS INTENSITIES OF PYRIDINE AND ITS DERIVATIVES ADSORBED ON AG ELECTRODES Peer-reviewed

    M KOBAYASHI, M IMAI

    SURFACE SCIENCE　158　(1-3)　275-285　1985

    ISSN： 0039-6028

Show all ︎Show first 5

Misc. 85

  1. pH sensing by lipids in membranes: The fundamentals of pH-driven migration, polarization and deformations of lipid bilayer assemblies Invited Peer-reviewed

    Miglena I. Angelova, Anne-Florence Bitbol, Michel Seigneuret, Galya Staneva, Atsuji Kodama, Yuka Sakuma, Toshihiro Kawakatsu, Masayuki Imai, Nicolas Puff

    Biochimica et Biophysica Acta - Biomembranes　2018

    Publisher: Elsevier B.V.

    DOI： 10.1016/j.bbamem.2018.02.026 　

    ISSN： 1879-2642 0005-2736

  2. Locomotion and Transformation of Underwater Micrometer-Sized Molecular Aggregates under Chemical Stimuli

    Taro Toyota, Taisuke Banno, Juan M. Castro, Masayuki Imai

    JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN　86　(10)　101006　2017/10

    DOI： 10.7566/JPSJ.86.101006 　

    ISSN： 0031-9015

  3. From vesicles to protocells: The roles of amphiphilic molecules

    Yuka Sakuma, Masayuki Imai

    Life　5　(1)　651-675　2015/03/02

    Publisher: MDPI AG

    DOI： 10.3390/life5010651 　

    ISSN： 2075-1729

  4. 30pAC-8 Three-Dimensional Analysis of Self-reproducing Vesicles

    Jimbo T., Sakuma Y., Urakami N., Ziherl Primoz, Imai M.

    Meeting abstracts of the Physical Society of Japan　69　(1)　440-440　2014/03/05

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  5. 30pAC-10 拘束条件及びトポロジーの違いによるベシクル変形機構の解明(30pAC 膜・ミセル,領域12(ソフトマター物理・化学物理・生物物理))

    坂下 あい, 今井 正幸, 野口 博司

    日本物理学会講演概要集　69　(1)　440-440　2014/03/05

    Publisher: 一般社団法人日本物理学会

    ISSN： 1342-8349

  6. Approach to the Protocell from Vesicles

    Yuka Sakuma, Masayuki Imai

    membrane　39　(5)　316-321　2014

    Publisher: The membrane society of Japan

    DOI： 10.5360/membrane.39. 　

  7. Physics of Heterogeneous Structures in Biomembranes

    SHigeyuki Komura, Masayuki Imai

    Butsuri　68　(11)　714-722　2013/11

    Publisher: The Physical Society of Japan

    ISSN： 0029-0181

    More details Close

    Since the notion of lipid rafts has been proposed, the traditional view of biomembranes based on the fluid mosaic model has been renewed. In the raft model, dynamical heterogeneity occurring in multi-component lipid membranes plays an essential role. In this review article, we mainly discuss lateral phase separation in biomembranes and vesicles, and provide with an overview of the research trend during the past decade. We shall mainly review the experimental works from the viewpoint of physical chemistry, and interpret these phenomena using soft matter physics. We first explain phase behavior and conformation of multi-component lipid bilayer membranes. By formulating the hydrodynamics of a fluid membrane including the surrounding solvent, we discuss the domain growth-law and concentration fluctuations in membranes.

  8. Tubular formation of lipid vesicles induced by coupling of spontaneous curvature and phase separation

    Sakuma Yuka, Taniguchi Takashi, Kawakatsu Toshihiro, Imai Masayuki

    Meeting abstracts of the Physical Society of Japan　68　(2)　308-308　2013/08/26

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  9. Drastic deformation of phospholipid vesicles coupled with chemophoresis

    Kodama Atsuji, Sakuma Yuka, Imai Masayuki, Kawakatsu Toshihiro

    Meeting abstracts of the Physical Society of Japan　68　(2)　308-308　2013/08/26

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  10. Three-Dimensional Analysis of Self-reproducing Vesicles

    Jimbo T., Sakuma Y., Urakami N., Ziherl P., Imai M.

    Meeting abstracts of the Physical Society of Japan　68　(2)　307-307　2013/08/26

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  11. From vesicle to protocell

    Yuka Sakuma, Masayuki Imai

    ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY　245　2013/04

    ISSN： 0065-7727

  12. 28pXC-4 Chemophoresis of neutral phospholipid vesicles

    Kodama Atsuji, Sakuma Yuka, Imai Masayuki, Kawakatsu Toshihiro

    Meeting abstracts of the Physical Society of Japan　68　(1)　440-440　2013/03/26

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  13. 28pXC-7 Lipid membrane deformation triggered by chemical stimulation

    Sakuma Yuka, Bitbol Anne-Florence, Puff Nicolas, Imai Masayuki, Fournier Jean-Baptiste, Angelova Miglena I.

    Meeting abstracts of the Physical Society of Japan　68　(1)　440-440　2013/03/26

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  14. 28pXC-3 Slow Dynamics of Soft Spherical Particles

    Imai Masayuki, Sakuma Yuka, Kawakatsu Toshihiro

    Meeting abstracts of the Physical Society of Japan　68　(1)　439-439　2013/03/26

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  15. Lipid Sorting Revealed by SANS

    Yuka Sakuma, Masayuki Imai

    Hamon　23　(1)　56-61　2013/02

    Publisher: The Japanese Society for Neutron Science

    ISSN： 1349-046X

  16. 26pBJ-14 ベシクル変形機構の解明 : 三次元画像解析によるアプローチ(26pBJ 膜・ミセル,領域12(ソフトマター物理,化学物理,生物物理))

    坂下 あい, 浦上 直人, Ziherl Primoz, 今井 正幸

    日本物理学会講演概要集　67　(1)　418-418　2012/03/05

    Publisher: 一般社団法人日本物理学会

    ISSN： 1342-8349

  17. Model of Self Reproducing Vesicles

    Yuka Sakuma, Masayuki Imai

    BIOPHYSICAL JOURNAL　102　(3)　33A-33A　2012/01

    ISSN： 0006-3495

  18. Lipid Membrane Deformation in Response to a Local pH Modification

    Anne-Florence Bitbol, Nicolas Puff, Yuka Sakuma, Masayuki Imai, Jean-Baptiste Fournier, Miglena I. Angelova

    BIOPHYSICAL JOURNAL　102　(3)　33A-33A　2012/01

    ISSN： 0006-3495

  19. 22pJF-6 Asymmetric Distribution of Lipids Induced by Membrane Curvature

    Sakuma Yuka, Imai Masayuki

    Meeting abstracts of the Physical Society of Japan　66　(2)　320-320　2011/08/24

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  20. 25aGT-11 Three-Dimensional Analysis of Vesicle Morphologies

    Sakashita Ai, Urakami Naohito, Ziherl Primoz, Imai Masayuki

    Meeting abstracts of the Physical Society of Japan　66　(1)　371-371　2011/03/03

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  21. 26aPS-5 Three-Dimensional Analysis of Vesicle Morphologies

    Sakashita Ai, Urakami Naohito, Ziherl Primoz, Imai Masayuki

    Meeting abstracts of the Physical Society of Japan　65　(2)　340-340　2010/08/18

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  22. 25pTB-12 Birthing Dynamics of Vesicles

    Sakuma Yuka, Imai Masayuki

    Meeting abstracts of the Physical Society of Japan　65　(2)　336-336　2010/08/18

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  23. 23aPS-102 Deformation of vesicles controlled by spontaneous curvatures of lipids

    Sakuma Yuka, Taniguchi Takashi, Kawakatsu Toshihiro, Imai Masayuki

    Meeting abstracts of the Physical Society of Japan　65　(1)　402-402　2010/03/01

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  24. 生体膜における液体ドメインの拡散係数

    好村滋行, RAMACHANDRAN S, 今井正幸, 関和彦

    日本物理学会講演概要集　65　(1)　370-370　2010/03/01

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  25. Shape deformations of multicomponent vesicles

    Masayuki Imai, Yuka Sakuma

    Advances in Planar Lipid Bilayers and Liposomes　12　(C)　41-78　2010

    DOI： 10.1016/B978-0-12-381266-7.00003-1 　

    ISSN： 1554-4516

  26. Diffusion of Nano-Meter-Sized Domains on A Vesicle

    Yuka Sakuma, Masayuki Imai, Naohito Urakami, Michihiro Nagao, Shigeyuki Komura, Toshihiro Kawakatsu

    BIOPHYSICAL JOURNAL　98　(3)　220A-220A　2010/01

    ISSN： 0006-3495

  27. Deformation of Vesicles Controlled by Local Spontaneous Curvatures of Membrane

    Yuka Sakuma, Masayuki Imai, Takashi Taniguchi, Toshihiro Kawakatsu

    BIOPHYSICAL JOURNAL　98　(3)　665A-666A　2010/01

    ISSN： 0006-3495

  28. ベシクル膜面上でのナノドメインダイナミクス

    佐久間由香, 浦上直人, 緒方祐介, 長尾道弘, 好村滋行, 川勝年洋, 今井正幸

    日本物理学会講演概要集　64　(2)　248-248　2009/08/18

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  29. 30aPS-110 Development of 3D-Imaging Technique for Giant Vesicles

    Horii Kanako, Imai Masayuki, Urakami Naohito

    Meeting abstracts of the Physical Society of Japan　64　(1)　389-389　2009/03/03

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  30. 30aPS-114 Deformation of vesicles controlled by spontaneous curvatures of lipids

    Sakuma Yuka, Taniguchi Takashi, Kawakatsu Toshihiro, Imai Masayuki

    Meeting abstracts of the Physical Society of Japan　64　(1)　390-390　2009/03/03

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  31. 27pVB-8 Periodic domain structures on modulated tubular vesicles

    Yanagisawa M., Imai M., Taniguchi T.

    Meeting abstracts of the Physical Society of Japan　64　(1)　358-358　2009/03/03

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  32. ナノスケールにおける脂質ドメインの拡散

    佐久間由香, 今井正幸, 浦上直人, 長尾道弘, 好村滋行, 川勝年洋

    日本中性子科学会年会講演概要集　9th　58　2009

  33. 21pWE-5 Deformation of vesicles controlled by spontaneous curvatures of lipids

    Sakuma Yuka, Imai Masayuki, Kawakatsu Toshihiro, Taniguchi Takashi

    Meeting abstracts of the Physical Society of Japan　63　(2)　317-317　2008/08/25

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  34. 21pWE-6 Lamellar-to-nematic phase transition in C12E5/rac-DMPC/Water system

    Yanagisawa M., Navailles L., Nallet F., Imai M.

    Meeting abstracts of the Physical Society of Japan　63　(2)　318-318　2008/08/25

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  35. 23aYC-4 2-Dimensional Honeycomb Packed Multilamellar Vesicles Induced by Shear Flow.

    Suganuma Y., Medronho B., Imai M., Kato T., Olsson U.

    Meeting abstracts of the Physical Society of Japan　63　(1)　349-349　2008/02/29

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  36. 25pPSB-37 Development of 3D-Tomography Technique for Giant Vesicles

    Horii Kanako, Imai Masayuki, Urakami Naohito

    Meeting abstracts of the Physical Society of Japan　63　(1)　380-380　2008/02/29

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  37. 25pPSB-48 Dynamics of lipid domain on a nano-meter sized vesicle

    Ogata Yusuke, Urakami Naohito, Yamamoto Takashi, Imai Masayuki

    Meeting abstracts of the Physical Society of Japan　63　(1)　382-382　2008/02/29

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  38. Shape deformation of vesicle coupled with phase separation Peer-reviewed

    M. Yanagisawa, M. Imai, T. Taniguchi

    AIP Conference Proceedings　982　667-671　2008

    DOI： 10.1063/1.2897875 　

  39. 18pRE-12 Hydrodynamics in mixed biomembranes

    Meeting abstracts of the Physical Society of Japan　62　(1)　329-329　2007/02/28

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  40. Dynamical Structure of Nano-Meter-Sized Domains on a Vesicle(Poster session 1, New Frontiers in Colloidal Physics : A Bridge between Micro- and Macroscopic Concepts in Soft Matter) :

    Sakuma Yuka, Masui Tomomi, Imai Masayuki, Urakami Naohito, Nagao Michihiro, Komura Shigeyuki

    89　(1)　45-45　2007

    Publisher: 物性研究刊行会

    ISSN： 0525-2997

  41. Adhesion of Binary Vesicles Induced by Phase Separation(Poster session 2, New Frontiers in Colloidal Physics : A Bridge between Micro- and Macroscopic Concepts in Soft Matter) :

    Sakuma Yuka, Imai Masayuki, Komura Shigeyuki

    89　(1)　116-116　2007

    Publisher: 物性研究刊行会

    ISSN： 0525-2997

  42. 25aWG-3 Binding transition of vesicles induced by lateral phase separation

    Sakuma Y., Imai M., Yanagisawa M., Komura S.

    Meeting abstracts of the Physical Society of Japan　61　(2)　273-273　2006/08/18

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  43. 24pPSB-5 Non-Equilibrium Shape Transformation of Ternary Vesicles Coupled with Phase Separation

    Yanagisawa M., Imai M.

    Meeting abstracts of the Physical Society of Japan　61　(2)　261-261　2006/08/18

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  44. Elementary process of polymer crystallization and self-organization

    Keisuke Kaji, Koji Nishida, Toshiji Kanaya, Go Matsuba, Takashi Konishi, Masayuki Imai

    SEN-I GAKKAISHI　62　(4)　P88-P92　2006/04

    ISSN： 0037-9875

  45. 27aRH-4 Growth dynamics of liquid domains on lipid bilayer

    Yanagisawa M., Imai M., Masui T., Komura S., Ohta T.

    Meeting abstracts of the Physical Society of Japan　61　(1)　344-344　2006/03/04

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  46. 27aRH-5 Morphorogy transition of lamellar phase induced by addition of colloidal patricles

    Suganuma Y., Imai M., Mawatari R., Nakaya K., Komura S.

    Meeting abstracts of the Physical Society of Japan　61　(1)　344-344　2006/03/04

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  47. 高分子の拘束が誘起する球状マイクロエマルションのネマチック転移

    中谷香織, 今井正幸, 好村滋行, 川勝年洋, 浦上直人

    日本液晶学会討論会講演予稿集　2005　(2005)　59-60　2005/09/05

    Publisher: Japanese Liquid Crystal Society

    ISSN： 1880-3490

  48. 時分割X線小角散乱によるミセル/ラメラ相分離過程の追跡

    柿澤みのり, 川端庸平, 好村滋行, 加藤直, 今井正幸

    コロイドおよび界面化学討論会講演要旨集　58th　110　2005/08/22

  49. 高分子の拘束が誘起する球状マイクロエマルションのネマチック転移

    中谷香織, 今井正幸, 好村滋行, 川勝年洋, 浦上直人

    コロイドおよび界面化学討論会講演要旨集　58th　117　2005/08/22

  50. 21aXJ-5 Growth dynamics of microdomains on model bio membrane

    Yanagisawa M., Imai M., Motoyama M., Masui T.

    Meeting abstracts of the Physical Society of Japan　60　(2)　241-241　2005/08/19

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  51. 25pZD-12 Kelvin Problem and Spherical Micelle Crystal

    Imai M., Yoshida I.

    Meeting abstracts of the Physical Society of Japan　60　(1)　361-361　2005/03/04

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  52. 高分子鎖の閉じ込めが誘起するマイクロエマルションのネマチック転移

    中谷香織, 今井正幸, 好村滋行, 川勝年洋, 浦上直人

    日本中性子科学会年会講演概要集　4th　93　2004

  53. 高分子鎖の拘束が誘起する膜の構造転移

    中谷香織, 今井正幸, 好村滋行, 浦上直人

    日本中性子科学会年会講演概要集　3rd　76　2003/12/10

  54. 高分子鎖が誘起する球状膜の構造転移と高次構造形成

    中谷香織, 今井正幸, 好村滋行, 浦上直人

    高分子学会予稿集　52　(10)　2545-2546　2003/09/10

  55. 分子膜とゲスト成分複合系の膜間相互作用

    今井正幸, 馬渡理奈, 中谷香織, 好村滋行

    高分子学会予稿集　52　(9)　1879-1880　2003/09/10

  56. 高分子が誘起する球状膜から棒状膜への構造転移

    中谷香織, 今井正幸, 好村滋行

    コロイドおよび界面化学討論会講演要旨集　56th　170　2003/08/22

  57. Morphology Transition of Microemulsion Droplet Induced by Polymer Chains Confinement

    Nakaya Kaori, Imai Masayuki, Komura Shigeyuki

    Meeting abstracts of the Physical Society of Japan　58　(2)　301-301　2003/08/15

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  58. Least Stable Fluctuation Modes of Lamellar Structure Observed in a Non-ionic Surfactant/Water System

    Imai M., Nakaya K., Kawakatsu T., Seto H.

    Meeting abstracts of the Physical Society of Japan　58　(1)　346-346　2003/03/06

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  59. ゲスト成分が変調するラメラ膜間相互作用(ソフトマターの物理学2003-普遍性と多様性-,研究会報告)

    今井 正幸, 馬渡 理奈, 中谷 香織, 好村 滋行

    物性研究　81　(2)　226-227　2003

    Publisher: 物性研究刊行会

    ISSN： 0525-2997

  60. Spinodal Decomposition Type Crystal Nucleation of Polymers

    K. Kaji, K. Kaji, K. Nishida, M. Imai, G. Matsuba, T. Kanaya

    International Symposium on Polymer Crystallization (Grant-in aid for Science on Priority Area) ,Mishima, Japan　2002/06/11

  61. 24aYB-6 Phase behavior in the mixture system of rod particles and chains.

    Urakami Naohito, Imai Masayuki

    Meeting abstracts of the Physical Society of Japan　57　(1)　302-302　2002/03/01

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  62. 24aYB-5 Polymer Induced Ordering of Rod-likf Particles

    Imai Masayuki, Nakamura Atsumi, Yamashita Haruka, Takada Ran, Oikawa Reiko, Urakami Naohito

    Meeting abstracts of the Physical Society of Japan　57　(1)　302-302　2002/03/01

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  63. Dynamical Structure of Microemulsion Droplets Confining a Polymer Chain

    Nakaya K., Imai M., Takeda T., Seto H., Kawabata Y.

    Meeting abstracts of the Physical Society of Japan　56　(2)　256-256　2001/09/03

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  64. 高分子が誘起する球状マイクロエマルションの構造転移

    中谷香織, 今井正幸, 好村滋行, 川勝年洋

    日本中性子科学会年会講演概要集　1st　59　2001

  65. Kinetics of Lamellar-Gyroid Transition Observed in a Nonionic Surfactant/Water System

    Imai Masayuki, Nakaya Kaori, Kawaguchi Ayako, Kato Tadashi, Ito Kazuki

    Meeting abstracts of the Physical Society of Japan　55　(2)　302-302　2000/09/10

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  66. Conformational Change and Orientation Fluctuations Prior to Crystallization of Crystalline Polysty-renes (FUNDAMENTAL MATERIAL PROPERTIES-Polymer Materials Science)

    Matsuba Go, Kaji Keisuke, Nishida Koji, Kanaya Toshiji, Imai Masayuki

    ICR annual report　6　26-27　2000/03

    Publisher: Institute for Chemical Research, Kyoto University

    ISSN： 1342-0321

  67. 26aP-11 The configuration transition of the tobacco mosaic virus with polysaccharides

    URAGAMI Nanohito, IMAI Masayuki, SANO Yoh, TAKASU Masako

    Meeting abstracts of the Physical Society of Japan　54　(2)　315-315　1999/09/03

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  68. 24pN-8 Slow Dynamics of Morphology Transition observed in a Surfactant/Water System

    IMAI Masayuki, NAKATANI Kaori, KAWAGUCHI Ayako, KATO Tadashi, ITO Kazuki, AMEMIYA Yoshiyuki

    Meeting abstracts of the Physical Society of Japan　54　(2)　294-294　1999/09/03

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  69. Structure of a lamellar phase formed by non-ionic surfactant and water - Effects of shear flow

    K Minewaki, T Kato, H Yoshida, M Imai

    JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY　57　(3)　753-758　1999/09

    DOI： 10.1023/A:1010121603917 　

    ISSN： 1418-2874

  70. 29a-XG-10 Kinetics of Morphology Transition in a Surfactant

    Imai Masayuki, Nakaya Kaori, Kato Tadashi, Ito Kazuki, Amemiya Yoshiyuki

    Meeting abstracts of the Physical Society of Japan　54　(1)　726-726　1999/03/15

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  71. A New Discovery of Microphase Separation Initiating In the Induction Period of Polymer Crystallization : characteristic wavelengths at high temperatures (FUNDAMENTAL MATERIAL PROPERTIES-Polymer Materials Science)

    Kaji Keisuke, Matsunaga Shuji, Matsuba Go, Kanaya Toshiji, Nishida Koji, Imai Masayuki

    ICR annual report　5　26-27　1999/03

    Publisher: Institute for Chemical Research, Kyoto University

    ISSN： 1342-0321

  72. The effects of polysaccharides concentration on the tobacco mosaic virus configuration II

    URAKAMI Naohito, IMAI Masayuki, SANO Yoh, TAKASU Masako

    Meeting abstracts of the Physical Society of Japan　53　(2)　829-829　1998/09/05

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  73. The effects of polysaccbarides concentration on the tobacco mosaic virus configuration

    URAKAMI Naohito, IMAI Masayuki, SANO Yoh, TAKASU Masako

    Meeting abstracts of the Physical Society of Japan　53　(1)　705-705　1998/03/10

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  74. 7p-YA-5 Neutron spin echo study of network of worm-like micelles

    Seto H., Kato T., Takeda T., Nagao M., Okuhara D., Kawabata Y., Imai M.

    Meeting abstracts of the Physical Society of Japan　52　(2)　844-844　1997/09/16

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  75. Self-assembly in ternary microemulsion systems III, interactions

    Komura S., S.K Ghosh, Matsuba J., Seto H., Takeda T., Hikosaka M., Imai M.

    Abstracts of the meeting of the Physical Society of Japan. Sectional meeting　1996　(3)　759-759　1996/09/13

    Publisher: The Physical Society of Japan (JPS)

  76. Self-assembly in ternary microemulsion systems I, mean curvature

    Matsuba J., S.K Ghosh, Komura S., Seto H., Takeda T., Hikosaka M., Imai M.

    Abstracts of the meeting of the Physical Society of Japan. Sectional meeting　1996　(3)　758-758　1996/09/13

    Publisher: The Physical Society of Japan (JPS)

  77. Self-assembly in ternary microemulsion systems II, structure functions

    S.K Ghosh, Matsuba J., Komura S., Seto H., Takeda T., Hikosaka M., Imai M.

    Abstracts of the meeting of the Physical Society of Japan. Sectional meeting　1996　(3)　758-758　1996/09/13

    Publisher: The Physical Society of Japan (JPS)

  78. 31p-A-5 What happens during the induction period of polymer crystal nucleation?

    Imai M., Kaji K., Kanaya T.

    Abstracts of the meeting of the Physical Society of Japan. Annual meeting　51　(3)　715-715　1996/03/15

    Publisher: The Physical Society of Japan (JPS)

  79. PRECURSOR FLUCTUATIONS OF MARTENSITIC PHASE TRANSITION ON METALLIC SODIUM.

    H. Abe, R. J. Matsuo, K. Ohshima, M. Imai, K. Kakurai

    ACTA CRYSTALLOGRAPHICA A-FOUNDATION AND ADVANCES　52　C427-C427　1996

    DOI： 10.1107/S0108767396082414 　

    ISSN： 2053-2733

  80. Structural formation of microemulsions in water/oil/AOT ternary system III

    Komura S., Seto H., Yokoi E., Nagao M., Ito Y., Imai M.

    Abstracts of the meeting of the Physical Society of Japan. Annual meeting　50　(3)　676-676　1995/03/16

    Publisher: The Physical Society of Japan (JPS)

  81. Crossover from Meanfield to 3D-Ising Critical Behavior in 3-component Microemulsion II

    Seto H., Nagao M., Yokoi E., Komura S., Schwahn D., Imai M., Mortensen K.

    Abstracts of the meeting of the Physical Society of Japan. Annual meeting　50　(3)　676-676　1995/03/16

    Publisher: The Physical Society of Japan (JPS)

  82. Crystal Nucleation in Polymer Glasses (FUNDAMENTAL MATERIAL PROPERTIES - Polymer Materials Science)

    Imai Masayuki, Kaji Keisuke, Kanaya Toshiji

    ICR annual report　1　26-27　1995/03

    Publisher: Institute for Chemical Research, Kyoto University

    ISSN： 1342-0321

  83. 3a-B-5 A Crossover from Meanfield to 3D-Ising Critical Behavior in Microemulsion

    Seto H, Nagao M, Yokoi E, Komura S, Schwahn D, Imai M

    Abstracts of the meeting of the Physical Society of Japan. Sectional meeting　1994　(3)　551-551　1994/08/16

    Publisher: The Physical Society of Japan (JPS)

  84. 28p-WA-2 Structural formation of microemulsions in water/oil/AOT ternary system

    Komura S, Seto H, Yokoi E, Nagao M, Ito Y, Imai M

    Abstracts of the meeting of the Physical Society of Japan. Annual meeting　49　(3)　600-600　1994/03/16

    Publisher: The Physical Society of Japan (JPS)

  85. 28p-WA-3 A Phase Separation Process in 3-component Microemulsion

    Seto H, Yokoi E, Nagao M, Komura S, Imai M, Suzuki J, Ohnuma M, Schwahn D

    Abstracts of the meeting of the Physical Society of Japan. Annual meeting　49　(3)　600-600　1994/03/16

    Publisher: The Physical Society of Japan (JPS)

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Books and Other Publications 6

  1. The giant vesicle book

    Imai Masayuki, and Peter Wald

    CRC Press, Taylor & Francis Group　2020/10

    ISBN: 9781498752176

  2. Encyclopedia of Polymeric Nanomaterials

    Yuka Sakuma, Masayuki Imai

    Springer　2015

    ISBN: 9783642296475

  3. The Structure and Function f Biological Membranes

    佐久間由香, 今井正幸

    Kagakudojin　2014/10/30

  4. Dynamics of Heterogeneity in Fluid Membranes

    S. Komura, S. Ramacandran, K. Seki, M. Imai

    Elsevier　2012

  5. Shape deformations of multi-component vesicles

    M. Imai, Y. Sakuma

    Elsevier　2010

  6. ソフトマターの秩序形成

    今井正幸

    シュプリンガー・ジャパン　2007

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Presentations 19

  1. Morphology of vesicle aggregates International-presentation Invited

    Kei Murakami, Takuma Kono, Ryuta Ebihara, Yuka Sakuma, Masayuki Imai, Primož Ziherl

    Mini Conference on Physical Chemistry of Molecular Assembly　2019/01/12

  2. 情報高分子と連携したベシクルの増殖：ミニマルセルへの新しい道 Invited

    栗栖稔, 青木春隆, 神保岳大, 佐久間由香, 今井正幸

    細胞を創る研究会 11.0　2018/10/19

  3. 情報分子と連携したベシクルの増殖：ミニマルセルへの新しい道 Invited

    栗栖稔, 青木春隆, 神保岳大, 佐久間由香, 今井正幸, S. Luginbühl, P. Walde

    第６９回コロイドおよび界面科学討論会　2018/09/18

  4. Reproduction of Vesicles Coupled with Template Polymerization: Toward Self-Reproducing Automaton International-presentation Invited

    IMAI Masayuki

    International Liquid Crystal Conference 2018　2018/07/24

  5. Morphology of a Model Multicellular Organism International-presentation Invited

    IMAI Masayuki

    Nano-structured soft matter　2018/06/25

  6. Vesicle Growth Coupled with Template Polymerization - Toward Vesicle Based Self-Reproducing Automaton - Invited

    IMAI Masayuki

    Cell-Free Synthetic Biology Workshop　2017/11/25

  7. Morphologies in Vesicle-Vesicle Adhesion International-presentation Invited

    IMAI Masayuki

    Association in Solution IV　2017/08/02

  8. Self-reproduction of vesicles: membrane physics approach International-presentation

    Masayuki Imai

    International workshop “Expanding the evolutionary potential of minimal living systems”　2017/06/20

  9. Self-reproduction of vesicles: membrane physics approach International-presentation

    Masayuki Imai

    The Origin of Life - Synergy among the RNA, Protein and Lipid Worlds -　2017/05/28

  10. ミニマルセル − 分子集合体と生命をつなぐもの –

    今井正幸

    液晶学会ソフトマターフォーラム第１６回講演会　2017/01/13

  11. ベシクルからプロトセルへの道：ソフトマターからのアプローチ

    山田研究会「生物と非生物をつなぐ」　2015/11/16

  12. ベシクルからプロトセルへのアプローチ

    日本膜学会第３６回年会　2014/05/12

  13. Chemophoresis of Vesicle International-presentation

    Workshop on Cross Correlation & Transport Phenomena in Soft Matter　2014/01/27

  14. From Vesicle to Protocell International-presentation

    Yuka Sakuma

    245th ACS National Meeting　2013/04/07

  15. Vesicle Dynamics Triggered by Chemical Stimuli International-presentation

    Atsuji Kodama, Yuka Sakuma, Toshihiro Kawakatsu

    German-Japan Workshop Soft Matter in Nonequilibrium　2013/02/16

  16. Molecular Assembly to Protocell International-presentation

    Japanese-German-French workshop “Physics of Active Soft Matter”　2012/09/24

  17. Molecular assembly to protocell International-presentation

    Yuka Sakuma

    ECI conference: Association in Solution III　2012/07/23

  18. Slow dynamics of soft spheres International-presentation

    1st Asia-Oceania Conference on Neutron Scattering　2011/11/20

  19. Slow dynamics in crystallization of soft spheres International-presentation

    The 4th international discussion meeting on glass transition　2011/02/28

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Industrial Property Rights 1

  1. 2成分ベシクルによるマイクロメートルサイズの物質輸送システム

    佐久間由香, 今井正幸

    第5423043号

    Property Type: Patent

Research Projects 31

  1. Physics from molecular assembly toward cellular life Competitive

    System: Grant-in-Aid for Scientific Research

    2010/04 - Present

  2. Evolvable Self-Reproducing Minimal Cells: Toward Artificial Living Systems

    Offer Organization: Japan Society for the Promotion of Science

    System: Grants-in-Aid for Scientific Research

    Category: Grant-in-Aid for Scientific Research (A)

    Institution: Tohoku University

    2023/04/01 - 2026/03/31

  3. Development of Hierarchical Computational Technique for Complex Flows in Surfactant/polymer Composites

    Offer Organization: Japan Society for the Promotion of Science

    System: Grants-in-Aid for Scientific Research

    Category: Grant-in-Aid for Scientific Research (B)

    Institution: Tohoku University

    2022/04/01 - 2025/03/31

  4. Non-Equilibrium Thermodynamic Conditions for Emergence of Life Revealed by Minimal Cells

    Offer Organization: Japan Society for the Promotion of Science

    System: Grants-in-Aid for Scientific Research

    Category: Grant-in-Aid for Scientific Research (A)

    Institution: Tohoku University

    2020/04/01 - 2023/03/31

  5. Mechanical Model of Cancer Cells and Its Application to Pathology

    Imai Masayuki

    Offer Organization: Japan Society for the Promotion of Science

    System: Grants-in-Aid for Scientific Research

    Category: Grant-in-Aid for Challenging Research (Exploratory)

    Institution: Tohoku University

    2020/07/30 - 2022/03/31

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    The morphologies of the model cellular tissue has been investigate by experiments and a mechanical model based on membrane elasticity theory. The morphology of the model tissue is determined by the balance of adhesion force, surface tension, and bending elastic force. This mechanical model well describes typical model tissue morphologies obtained in the experiments. Using this mechanical model, we attempted to reproduce the morphology of a tumor. We succeeded in reproducing the typical tumor tissue of cervical cancer and the phagocytic phenomenon called cannibalism of cancer cells by the mechanical model. However, it was difficult to extract the characteristics of cancer cells that can be applied to pathological diagnosis. Currently, we are working on the extraction of the unique morphology of cancer cells by culturing cancer cells.

  6. Multi-Cellular Tissues as a Platform for Aquatic Functional Materials

    Offer Organization: Japan Society for the Promotion of Science

    System: Grants-in-Aid for Scientific Research

    Category: Grant-in-Aid for Scientific Research on Innovative Areas (Research in a proposed research area)

    Institution: Tohoku University

    2020/04/01 - 2022/03/31

  7. Multiscale Simulations on Complex Flows in Polymer/Surfactant Systems

    Kawakatsu Toshihiro

    Offer Organization: Japan Society for the Promotion of Science

    System: Grants-in-Aid for Scientific Research

    Category: Grant-in-Aid for Scientific Research (B)

    Institution: Tohoku University

    2019/04/01 - 2022/03/31

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    Complex flows in a fluid with dispersed amphiphilic membranes (such as vesicles) are typical examples of target phenomena of multiscale simulations. We developped a multiscale simulation method, where the macroscopic flow is described by smoothed particle hydrodynamics (SPH) method, while the migration and diffusion opf amphiphilic molecules on the vesicle membrane are simulated by microscopic molecular models embedded in each of the SPH particles. With this formulation, we could simulate Marangoni flows coupled with the defromation of the vesicle. In this methodology, we succeeded in reproducing complex flow and deformation of vesicle by a combination of 3 techniques, i.e. tracing the membrane surface, parallel computation of flow and elastic deformation of the membrane, and the diffusion of amphiphilic molecules on the membrane surface.

  8. Physical and mathematical approaches to the deformation of vesicles---from contact to adhesion, fusion and budding

    Takagi Izumi

    Offer Organization: Japan Society for the Promotion of Science

    System: Grants-in-Aid for Scientific Research

    Category: Grant-in-Aid for Scientific Research (C)

    Institution: Tohoku University

    2016/07/19 - 2020/03/31

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    A vesicle is a lipid bilayer forming a spherical or toroidal shell. Its shape is determined as a closed surface which minimizes the sum of the bending energy and area-difference elastic energy, among surfaces having the prescribed surface area and enclosing volume. We found that the Euler-Lagrange equation is an integro-differential equation, which makes mathematical analysis of this model quite difficult. The rigorous analysis of the shape equation for axially symmetric surfaces remains open due to this difficulty. In addition, we considered reaction-diffusion equations with variable coefficients arising from models of two-phase vesicles as well as mechano-chemical models of biological pattern formation. We proved the existence and stability of steady-state solutions for some of such equations; however, we could not study the interaction between the (visco-)elastic deformation of membrane and the chemical patterning within the research period.

  9. Formulation and application of veriational approaches to non-equilibrium phenomena

    KAWAKATSU toshihiro

    Offer Organization: Japan Society for the Promotion of Science

    System: Grants-in-Aid for Scientific Research

    Category: Grant-in-Aid for Challenging Exploratory Research

    Institution: Tohoku University

    2016/04/01 - 2019/03/31

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    We discuss dynamics of soft matter under nonequilibrium state by utilizing variational principle on free energy and dissipation functional. Examples are taken from the following phenomena : 1) dynamics of vesicles in flow field, 2) translocation of a vesicle through a small pore, 3) structural transition of microphase separation of block copolymer, and 4) lubrication of a pair of solid walls covered by grafted polymers. We discussed the dynamics and steady states of these systems.

  10. Road from vesicles to protocells: metabolism, information, thermodynamics

    Imai Masayuki

    Offer Organization: Japan Society for the Promotion of Science

    System: Grants-in-Aid for Scientific Research

    Category: Grant-in-Aid for Scientific Research (A)

    Institution: Tohoku University

    2016/04/01 - 2019/03/31

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    This research aims to construct minimal cell having essence of biological functions by using non-biological substances, so-called soft materials, whereby we reveal physics underlying the life. We focused on molecular assembly systems composed of synthesizing information polymer encoding vesicle membrane and growth-division vesicle coupled with the synthesis of information polymer. We succeeded to demonstrate the reproduction of vesicles coupled with an enzymatic polymerization reaction (synthesis polyaniline: PANI-ES) occurring on the surface of vesicles composed of AOT and cholesterol. An important characteristic of this reproduction system is that the AOT/cholesterol vesicles encourage the synthesis of PANI-ES and PANI-ES promotes the growth of AOT vesicles. This mutual promotion kinetics captures an essential feature of minimal cells.

  11. Physical approach from soft matter to artificial cell

    Imai Masayuki

    Offer Organization: Japan Society for the Promotion of Science

    System: Grants-in-Aid for Scientific Research

    Category: Grant-in-Aid for Scientific Research on Innovative Areas (Research in a proposed research area)

    Institution: Tohoku University

    2013/06/28 - 2018/03/31

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    The purpose of this study is to create the molecular assembly (artificial cell) having the essential functions of cellular life (heredity using information molecules, metabolism, self-reproduction of container) and the self-propelling ability. We will reveal the physical background of the cellular life through the artificial cells. 1) We have succeeded to create two types of artificial cells. Both of them demonstrate the vesicle reproduction coupled with the information molecules. One of them shows a primitive model cell cycle comprising four discrete phases (ingestion, replication, maturity and division), i.e., repeatable cell division. Both artificial cell has a potential of heredity and evolvability through the information molecules. 2)We also succeeded to create self-propelled tubular vesicles triggered by chemical stimuli, where the migration is coupled with the wavy motion of the tube. These findings shed light on the way from the molecular assembly to the cellular life.

  12. Synergy of Fluctuation and Structure : Quest for Universal Laws in Non-Equilibrium Systems

    SANO Masaki, SASA Shin-ichi, ORIHARA Hiroshi, IMAI Masayuki, KOMURA Shigeyuki, KIMURA Yasuyuki, HIRANO Takuya, ICHIKAWA Masatoshi, MIYAZAKI Kunimasa, YOSHIKAWA Kenichi, SAKURAI Tatsunari, KOBAYASHI Kensuke

    Offer Organization: Japan Society for the Promotion of Science

    System: Grants-in-Aid for Scientific Research

    Category: Grant-in-Aid for Scientific Research on Innovative Areas (Research in a proposed research area)

    Institution: The University of Tokyo

    2013/06/28 - 2018/03/31

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    The innovative research area "Synergy of Fluctuation and Structure: Quest for Universal Laws in Non-Equilibrium Systems" strived to expand two major areas of non-equilibrium science; studies of non-equilibrium fluctuations and self-organizing structures. The steering committee supported the collaboration between research groups in our area. We also organized two international symposiums (SFS2015 and SFS2017) and many research meetings.

  13. Physics of development from molecular assembly to protocell

    Imai Masayuki, SAKUMA Yuka, URAKAMI Naohito, SUZUKI Kentaro

    Offer Organization: Japan Society for the Promotion of Science

    System: Grants-in-Aid for Scientific Research

    Category: Grant-in-Aid for Scientific Research (A)

    Institution: Tohoku University

    2013/04/01 - 2016/03/31

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    in this research we have investigated vesicle dynamics triggered by chemical stimuli, which might be the first step of the evolution from vesicles to cellular life. By applying chemical stimuli, vesicles show unique dynamics, such as migration, deformations, relevant to biological functions. We revealed that chemical modifications of the surface tension and molecular cross section are responsible for the observed vesicle dynamics. In addition we succeeded to synthesize a new artificial lipid precursor molecule, which is hydrolyzed to produce the membrane molecule at the membrane surface. The membrane molecules are incorporated into the vesicle membrane and causes the vesicle growth.The growing vesicle produces offspring vesicles by division. The vesicle division process was investigated by a molecular dynamics simulation. the simulation revealed that the coupling of molecular shape and vesicle shape plays an important role in the vesicle division.

  14. Coupling between Deformations of Vesicle and Chemical Stimuli: Approach from Soft Matter toward Cellular Life

    MASAYUKI Imai, URAKAMI Naohito

    Offer Organization: Japan Society for the Promotion of Science

    System: Grants-in-Aid for Scientific Research

    Category: Grant-in-Aid for Scientific Research (A)

    2010/05/31 - 2014/03/31

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    We have investigated vesicle deformations triggered by chemical stimuli to reveal the pathway from vesicles (molecular assemblies of lipids) to cellular life. First we established an experimental technique to examine vesicle deformation triggered by the chemical stimuli and then revealed a mechanism of a tubular membrane formation induced by pH gradient. In addition we found that chemical stimuli drive vesicles toward the chemical source, so-called chemophoresis. These observations clearly show that the chemical stimuli play important roles to develop cellular life from vesicle. In addition we succeeded to reproduce a self-production of vesicle using binary vesicles, which shed light on the pathway toward the protopcell.

  15. Swimming vesicle driven by artificial flagella

    IMAI Masayuki

    Offer Organization: Japan Society for the Promotion of Science

    System: Grants-in-Aid for Scientific Research

    Category: Grant-in-Aid for Challenging Exploratory Research

    2011 - 2012

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    In the living cellular systems, in order to propel the entities the chemical energy supplied through the medium is transformed to the mechanical energy using a various types of chemical engines. In this research we have investigated the mechanisms of prototypes of the chemical engines from the following two points of view; 1) screw motion of tubular vesicle triggered by chemical stimuli, and 2) asymmetry of the surface energy of vesicle triggered by chemical stimuli. For the former mechanism, we succeeded to reproduce the screw motion of fatty acid vesicles and for the latter mechanism, we found so-called chemophoresis (chemotaxis) of vesicles where neutral vesicles swim toward the source of the chemical stimulus.

  16. Phase Transition Dynamics of Soft matter Induced by Guest Components

    IMAI Masayuki, TANAKA Hajime, OKUMURA Ko

    Offer Organization: Japan Society for the Promotion of Science

    System: Grants-in-Aid for Scientific Research

    Category: Grant-in-Aid for Scientific Research on Priority Areas

    Institution: Ochanomizu University

    2006 - 2010

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    By adding guests, the host meso-scopic structures are destabilized owing to the additional entropic and/or energetic interactions. We have been investigated such mixing effects in three relevant systems, (i) functional deformations of vesicle induced by lipid mixing, (ii) ordering dynamics caused by dynamical heterogeneity in meso-scopic scale, and (iii) non-equilibrium dynamics of wetting on structured surface.

  17. Overview study on the creation of non-equilibrium soft matter physics

    OHTA Takao

    Offer Organization: Japan Society for the Promotion of Science

    System: Grants-in-Aid for Scientific Research

    Category: Grant-in-Aid for Scientific Research on Priority Areas

    Institution: Kyoto University

    2006 - 2010

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    In order to establish a new research field, the management group of Grant-in-Aid for Scientific Research on Priority Area "Creation of non-equilibrium soft matter physics: Structure and dynamics of mesoscopic systems" has been responsible for conducting four subgroups of the network project, i.e., "Molecular dynamics in structure-forming dense polymer systems", "Dynamics of mesoscopic structural transitions", "Dynamics of non-equilibrium structure", and "Theories and modeling". The public participation research which consisted of more than 50 groups has been led by the management group as well. For the purpose of promoting the network activity, the management group organized various kinds of meetings, symposiums, and workshops. The management group also kept the website of the network and prepared several reports.

  18. Morphology Formation Dynamics of Multi-Component Vesicles

    IMAI Masayuki, URAKAMI Naohito, NAKAYA Kaori

    Offer Organization: Japan Society for the Promotion of Science

    System: Grants-in-Aid for Scientific Research

    Category: Grant-in-Aid for Scientific Research (B)

    Institution: Ochanomizu University

    2007 - 2009

  19. 準結晶構造をもつソフトマターメソフェイズの探索

    今井 正幸

    Offer Organization: 日本学術振興会

    System: 科学研究費助成事業

    Category: 萌芽研究

    Institution: お茶の水女子大学

    2006 - 2007

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    最も準結晶構造に近いA15結晶を形成する非イオン性界面活性剤(CiEjと表記され、iは疎水性を担うメチレン鎖の炭素数、iは親水性を担うエチレンオキサイド基の数を表す)C12E8を用い、ミセル相から六方最密格子、体心立方格子、A15格子のミセル間相互作用と、形成される構造との相関を明らかにした。実験を中性子小角散乱(SANS)とX線小角散乱(SAXS)を用い、得られた散乱関数をモデル散乱関数でフィットし、構造因子を求めた。実験から得られた構造因子を再現するミセル間相互作用をモデルから計算し、その結果ミセル間には弱い湯川型の斥力ポテンシャルが存在する事を示した。さらに、中性子スピンエコー法(東京大学物性研究所・全国共同利用実験設備)により各秩序相に対する動的構造因子を測定し、ミセルのコロナ鎖がお互いに重なり合う事による、中間散乱関数の変化を実験的に捉える事に成功した(現在論文執筆中)。しかし、この結果をもとに親水鎖と疎水鎖の長さを変えた非イオン性界面活性剤を用いて、準結晶相ないしはσ相の探索を行ったが、求める構造は得られなかった。そこで、非イオン性界面活性剤の表面を高分子で修飾し、ミセル間相互作用を変調することにより新しい結晶構造が現れるか検討中である。

  20. Kinetics of structural transitions in polymeric systems ・・・properties of gyroid structure・・・

    OHTA Takao, HASEGAWA Hirokazu, NONOMURA Makiko, IMAI Masayuki

    Offer Organization: Japan Society for the Promotion of Science

    System: Grants-in-Aid for Scientific Research

    Category: Grant-in-Aid for Scientific Research (B)

    Institution: Kyoto University

    2004 - 2006

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    A cooperative research was carried out on block copolymers by Hasegawa group, on water and surfactant mixtures by Imai group and the theoretical investigation by Ohta-Nonomura group. Ohta and Nonomura studied the fundamental properties of the formation and the stability of the gyroid structure which is one of the characteristic features of soft matter. They applied the mode expansion method and computer simulations and found that Fddd structure as well as the ordinary mesoscopic structures is a stable thermal equilibrium structure whereas perforated lamellar structure is metastable. It was also found that Fddd structure appears also in the course of the transitions between gyroid structure and lamellar structure where the cubic symmetry of gyroid is broken. It is emphasized that these theoretical predictions are consistent with the experiments of Hasegawa group who carried out X-ray scattering and found a series of morphological transitions from lamellar, Fddd and gyroid structures. The experiments of Imai group showed that the transition kinetics in water/surfactant systems are quite different from those of block copolymers. Therefore, we need further theoretical and experimental investigations to clarify the universal features of the dynamics of soft matter.

  21. Soft Matter Complex Systems as Model Biological Systems

    IMAI Masayuki, NAKAYA Kaori, URAKAMI Naohito

    Offer Organization: Japan Society for the Promotion of Science

    System: Grants-in-Aid for Scientific Research

    Category: Grant-in-Aid for Scientific Research (B)

    Institution: Ochanomizu University

    2003 - 2005

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    In this project, we investigated the structure formation of Soft Matter Complex Systems as Model Biological Systems. Especially we focused on the following three complex systems, which may have relation to the biological functionalities. 1)Liquid crystal + polymer complex system : Biopolymers having anisotropic shapes, such as protein, virus and actin-filament, forms characteristic aggregates in the biological circumstance. The basic attractive interaction between the anisotropic particles may be originated from the so-called depletion interaction. In this study we found that the rigid polymer enhances the depletion interaction about 1000 times compared with the case of coil-like polymer chains. This is due to the large effective excluded volume of the rigid polymer chains. 2)Surfactant membrane + polymer chain (colloidal particle) system : We have investigated effects of a guest component (polymer or spherical colloidal particle) confined between flexible lamellar slits on the inter-lamellar interaction. The addition of the neutral polymer into the lamellar phase induces an attractive inter-lamellar interaction. On the other hand, the spherical colloidal particles confined between the flexible lamellar membranes reduce the undulational fluctuations of lamellae and bring a repulsive inter-lamellar interaction. 3)Polymer grafted surfactant membranes We have investigated the effects of grafted polymer chains on the bending modulus and the inter-membrane interactions of lamellar membranes. The bending modulus of the polymer grafted membranes increases in proportion to the square of the end to end distance of the polymer chain. The mushroom layer is renormalized to the membrane thickness, which enhances the repulsive Helfrich interaction. When the size of the decorated polymer chain increases to the inter-lamellar distance, however, the mushroom is squeezed so as to optimize the inter-lamellar potential. Further increase of the grafted polymer size brings a lamellar-lamellar phase separation.

  22. 小角散乱を用いた次世代ナノ構造解析

    橋本 竹治, 雨宮 慶幸, 今井 正幸, 小泉 智, 瀬戸 秀紀, 柴山 充弘

    Offer Organization: 日本学術振興会

    System: 科学研究費助成事業

    Category: 基盤研究(C)

    Institution: 京都大学

    2004 - 2004

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    小角散乱法は、ナノ構造の形成過程、消滅過程等ナノ構造の運動をその場・実時間観測を可能にするという長所を持ち、ナノサイエンス・ナノテクノロジーを支える基礎学問として小角散乱は今後ますます重要な地位を占めることが予想される。今までは小角散乱を用いたナノ構造解析が様々な分野で独自に発展しているが、分野間の情報交換が少なく、またSPring-8、PF、JAERI、KENSなどの大型共同利用施設との情報交換も希薄な現状にある。本研究の目的はこのような状況に鑑み、2006年の小角散乱国際会議(SAS2006)が日本で開催される事を契機に、小角散乱をキーワードに様々な分野を代表する研究者を集め、今後日本のナノ構造解析への方向性とそのための基礎学問・技術開発の重点化を議論するための企画調査である。 我々は数回にわたり、特に次世代に向けての小角散乱研究の方向性を以下の観点から重点的に討議をおこなった。(1)大型放射光施設(SPring-8、PF)を利用した新しいX線小角散乱測定技術の開発、(2)研究用原子炉(JRR-3M)、大強度陽子加速器計画中性子実験施設(J-PARC/JSNS)を見据えた新しい中性子小角散乱実験技術の開発、(3)小角散乱法および理論研究の発展に基づく次世代ナノサイエンスの創製、(4)小角散乱を用いたナノ構造研究を進める民間企業および散乱装置製造メーカーと大学間の産学連携の推進。これらの議論を全研究分野にわたり、且つ全国的規模で展開し、小角散乱を用いた次世代ナノ構造解析の方向性を定めるとともに、来る2006年我国で開催する国際会議SAS2006に向けて日本からの情報発信の準備を行うことができた。

  23. Applied mathematics of pattern formation in material sciences

    OHTA Takao, NONOMURA Makiko, SAKAMOTO Kunimochi, MIMURA Masayasu, IMAI Masayuki, KOBAYASI Ryo

    Offer Organization: Japan Society for the Promotion of Science

    System: Grants-in-Aid for Scientific Research

    Category: Grant-in-Aid for Scientific Research (B)

    Institution: HIROSHIMA UNIVERSITY

    2001 - 2003

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    We have carried out theoretical analysis and development of numerical method for studying various macroscopic and microscopic pattern formation in material sciences. In particular, we have investigated both numerically and analytically (1) structural transitions of mesophases in block copolymer melts (2) ordering dynamics of charged colloidal particles (3) dynamics of grain boundaries (4) domains dynamics of reactive phase separating systems and (5) formation of bacteria colony with chemotacsis. Some of these works have been performed in collaboration with experimentalists. Together with these studies, we have also developed fundamental theories of interface/grain boundary dynamics by means of singular perturbation and reduction method.

  24. Dynamics of Morphology Transition of Complex Liquids

    IMAI Masayuki, NAKAYA Kaori, OHTA Takao

    Offer Organization: Japan Society for the Promotion of Science

    System: Grants-in-Aid for Scientific Research

    Category: Grant-in-Aid for Scientific Research (A)

    Institution: OCHANOMIZU UNIVERSITY

    2000 - 2002

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    The target of this research project is to reveal dynamics of morphology transitions in complex liquids (soft matter). For this purpose we investigated the following three systems. 1. Order-order transition of surfactant/water systems and block copolymers. Characteristic fluctuation modes are observed prior to an order-order transition. Which brings the destination ordered phase through a meta stable intermediate phase. This behavior is well described by the Gintzburg-Landau scheme. Furthermore we developed a mode expansion theory, which reveals the kinetic pathway of the order-order transition. 2. Morphology transition of rod partical + polymer system. Addition of polymer to the rod particle suspension brings isotropic to nematic transition. This phenomenon is induced by compentition between translational entropy and mixing entropy(depletion interaction). We found that the semi-rigid polymer enhances the depletion interaction extensively (^~10^<3-4>) due to the large excluded volume effect.The Monte-Carlo simulation reproduces the observed phenomenon as a function of the chain rigidity. 3. Morphology transition of membrane + polymer system. Using microemulsion droplet phase, we can confine polymer chains into a nano-scale closed spherical container. The entropy loss of the polymer chain due to the confinement brings morphology transition in order to minimize the total free energy consisting of conformational entropy of the chain and elastic energy of the membrane.

  25. Crystallization mechanism of polymer

    KANAYA Toshiji, NISHIDA Kouji, IMAI Masayuki, FUKAO Kouji

    Offer Organization: Japan Society for the Promotion of Science

    System: Grants-in-Aid for Scientific Research

    Category: Grant-in-Aid for Scientific Research on Priority Areas

    Institution: Kyoto University

    2000 - 2002

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    We have studied formation mechanism of polymer crystallization, focusing our attention on induction period of crystallization before nucleation. This work can be classified into the following four subjects. (1)Structural formation in preparatory process of polymer crystallization : We have directly observed transformation process from molten state to mesomorphic state of isotactic polypropylene(iPP) using super temperature jump apparatus developed by our laboratory. (2)Polymer crystallization under shear flow : We have evaluated structure formation process of so-called shishi-kebab structure in crystallization of iPP under shear flow, using time resolved depolarized light scattering, small angel X-ray scattering, small angel neutron scattering and wide angel neutron scattering techniques. (3)Crystallization mechanism of polymers from oriented glass : In order clarify the mechanism of formation of so-called long period, we have studied crystallization process of oriented poly (ethylene terephthalate) using a time resolved wide angel scattering technique (4)We investigated effects of phase separation on polymer crystallization in mixture of rod-like polymers and flexible polymers and clarified depletion effects in polymer crystallization.

  26. メゾ空間に拘束された高分子の相転移

    今井 正幸, 中谷 香織

    Offer Organization: 日本学術振興会

    System: 科学研究費助成事業

    Category: 萌芽的研究

    Institution: お茶の水女子大学

    2000 - 2000

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    本研究では、界面活性剤にAOT、球体の内部に水相、球体外部の分散相にイソオクタンを用い、水溶性高分子(ゼラチン、ポリエチレンオキサイド(PEO))を用いることにより高分子鎖を球体内に閉じ込めその時の高分子鎖とマイクロエマルション膜の挙動を研究した。我々はまず、高分子鎖(高分子鎖の回転半径(Rg)はドロプレットサイズとほぼ同じ)を閉じ込めることによるMEドロプレットの振る舞いについて調べた。MBドロプレット内に高分子鎖を閉じ込めていくと、ドロプレット一個あたりの平均高分子鎖数が一本程度までは球形を保っているが、その濃度を越えるとドロプレットは大きく変形を始め、球状からシリンダー状へとモルフォロジー転移をするものと考えられる。また、内包する高分子鎖が一本程度の領域では高分子鎖のフローリー半径をR_F、高分子を閉じ込める前のドロプレットサイズをR_O、閉じ込めた後のサイズをRとするとR/R_O〜(R_F/R)^<0.6>の関係が得られ、これは閉じ込められた高分子鎖のエントロピーロスと膜の弾性エネルギーのバランスから得られる理論的予言R/R_O〜(R_F/R)^<0.8>と非常によい一致を示した。 次に、ドロプレット内部に閉じ込められた高分子鎖を観察するために重水素化AOTを合成し、膜からの散乱コントラストを消去することに成功した。得られた閉じ込められた高分子鎖からの散乱曲線はまだ予備的なもので今後検討することが必要な課題も多いが、希薄水溶液状態での高分子鎖の拡がりに比べ高分子鎖を膜内に閉じ込めた時のRgは大きく減少する結果が得られた。今後、重水素化AOTが作るMEの相挙動・高分子鎖との相互作用等解決すべき問題もあるが、最終目的であるメゾ空間に拘束された高分子鎖の相転移挙動を明らかにするべく研究を進めていく。

  27. Structural Formation during Induction Period of First Order Phase Transition

    IMAI Masayuki

    Offer Organization: Japan Society for the Promotion of Science

    System: Grants-in-Aid for Scientific Research

    Category: Grant-in-Aid for Scientific Research (C)

    1997 - 1999

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    In the first order phase transitions, we sometimes observe a waiting time prior to the phase transition, so-called induction period (incubation time). According to the classical nucleation theory the induction period is the time needed to form critical nucleus. However systems having multi-order parameters, such as complex liquids will show a variety of incubation time or pretransition behaviors arisen from coupling of the order parameters. The purpose of this study is to reveal the kinetics of the incubation time or pretransition phenomena in the first order phase transition of the complex liquids. 1) Ordering process of polymers during the induction period of crystallization. We found the ordering process in the induction period of polymer crystallization.When a poly(ethylene terephthalate) glass was annealed just above the glass transitio temperature, a new peak in the small angle x-ray scattering profiles appeared prior to the crystallization. The quantitative analysis of this peak revealed that a spinodal decomposition type of phase transition occurs as a preparatory process of the crystallization. The origin of this phenomenon is explained as the parallel orientational ordering of the rodlike polymer segments. 2) Pretransition phenomena observed in a order-order transition of a surfactant/water system. We investigated the lamellar structure prior to a lamellar-to-gyroid transition in a nonionic surfactant/water system. In high temperature region (T > 65℃) the lamellae show undulation fluctuations. When the temperature approached to the lamellar-to-gyroid transition temperature, the excess diffuse scattering grew around a first lamellar peak and then transformed to a (211) peak of the gyroid lattice at the transition temperature. This excess diffuse scattering arises from modulation or perforation of the lamellae. This modulated lamellae is the equlibrim pretransition structure and corresponds to the least stable mode of the lamellar structure.

  28. Study of Fluxon by Means of Neutron Scattering and Its Application to Engineering Science

    OSAMURA Kozo, OKUDA Hiroshi, IMAI Masayuki, HURASAKA Michihiro, ARAI Masatoshi, MATSUSHITA Teruo

    Offer Organization: Japan Society for the Promotion of Science

    System: Grants-in-Aid for Scientific Research

    Category: Grant-in-Aid for Scientific Research (A)

    Institution: KYOTO UNIVERSITY

    1995 - 1997

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    Detailed structural information on fluxon is important to make clear the mechanism of superconductivity and promote the electromagnetic studies. As the small-angle neutron scattering technique provides a useful information in the magnetic flux structure in type II superconductors, we applied this technique for following intensive studies together with scanning Hall probe technipue, magnetization and electrical resistivity measurement. (1) Anisotropy, dimensionality of FLL and magnetic phase diagram. (2) Structural deviation of FLL by pinning. (3) Dynamics of FLL due to phase transition and dimensional cross-over. (4) Inhomogeneous structure of FLL in LSCO single crystal. (5) Detailed structure of FLL by means of STM/STS.(6) Local magnetic flux distribution by means of scanning Hall probe measurement. (7) Analysis of magnetization process based on electromagnetic theory. The final discussion meeting was held at Kyoto on 2nd of March.

  29. 高分子の結晶化におけるミクロからメゾスコピックへの秩序形成

    今井 正幸

    Offer Organization: 日本学術振興会

    System: 科学研究費助成事業

    Category: 奨励研究(A)

    Institution: 東京大学

    1996 - 1996

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    高分子物質を非晶状態から結晶化させると、結晶核形成から結晶成長・球晶成長へと様々な空間的階層で秩序化過程が観察される。特に結晶核形成には系が結晶化条件に達してから実際に結晶化が開始するまでに誘導期間と呼ばれる過渡的な時間の経過が必要であり、最近我々のグループでは、この結晶化誘導期においてメゾスコピック領域での密度および配向ゆらぎの成長過程を観測した。本研究の目的は、このようなメゾスコピックな構造揺らぎと結晶化による原子レベルでのパッキングがどのように関連しているのかを明らかにすることである。我々は高エネルギー物理学研究所所有の高分解能中性子弾性散乱装置、HITを用いて、結晶化の初期過程における構造形成を原子レベルで行った。その結果、非晶状態と結晶化誘導期間にある試料でその散乱曲線S(Q)に約1%程度の差があることを見い出した。この違いはピーク位置より、分子鎖セグメントの秩序化に起因すると考えられ、平行して測定した赤外吸収スペクトルの変化とも対応し、メゾスコピックな構造揺らぎの原子レベルでの起源を明らかにするものである。現在この散乱曲線をもとに、コンピュタ-シミュレーションによりその構造モデルの構築を行っており、それにより誘導期間における構造形成がかなり明瞭になるものと期待される。

  30. 高分子の結晶化におけるメゾスコピックな秩序形成と動的構造

    今井 正幸

    Offer Organization: 日本学術振興会

    System: 科学研究費助成事業

    Category: 奨励研究(A)

    Institution: 東京大学

    1995 - 1995

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    高分子物質を非結晶状態から結晶化させると、ランダムに絡み合った一次元の高分子鎖が,秩序だった格子を組み始めるいわゆる、結晶核形成過程が観察される。この結晶核形成には系が結晶化条件に達してから実際に結晶化が開始するまでに誘導期間と呼ばれる過渡的な時間の経過が必要となる。我々は、従来殆ど解明されていなっかた結晶化誘導期に着目して研究を進め、この結晶化が開始する以前の段階においてメゾスコピックスケール(〜10nm)で密度と配向のゆらぎによる新しい秩序化過程を見い出した。当該年度においては、このメゾスコピックスケールでの新しい秩序形成と原子オーダーのミクロスコピックスケールでの構造形成を対応させるため、赤外吸収分光測定および広範囲中性子弾性散乱測定を行った。特に赤外吸収分光測定は同時DSC(示差熱分析)測定できる装置を用いマクロスコピックな結晶化誘導期を捉えながらin-situで分子鎖のゴ-シュ形からトランス形へのコンフォメーション変化を時間発展的に追跡した。その結果トランスコンフォメーションが結晶化によるパッキングが開始する前の誘導期において増大していることを直接的に明らかにした。この結果を小角X線散乱、小角中性子散乱、偏光解消光散乱の結果と併せると、誘導期におけるゴ-シュ形からトランス形へのコンフォメーション変化を引き金にして分子鎖の持続長が増大し、これが排除体積効果による分子鎖の平行配向化を進めて、上述のメゾスコピックスケールでの密度と配向のゆらぎをもたらすという我々のモデルを裏付けることができた。さらに、広範囲中性子弾性散乱測定により、このように形成されるメゾスコピックスケールでの密度ゆらぎが結晶化による分子鎖のパッキングよりかなり前の段階で形成されることも直接的に示された。

  31. 高分子の結晶化に伴う密度および配向ゆらぎの成長過程

    今井 正幸

    Offer Organization: 日本学術振興会

    System: 科学研究費助成事業

    Category: 重点領域研究

    Institution: 東京大学

    1995 - 1995

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    高分子物質を非晶状態から結晶化させると、ランダムに絡み合った一次元の高分子鎖が,秩序だった格子を組み始めるいわゆる、結晶核形成過程が観察される。この結晶核形成には系が結晶化条件に達してから実際に結晶化が開始するまでに誘導期間と呼ばれる過渡的な時間の経過が必要となる。我々は、従来殆ど解明されていなっかた結晶化誘導期に着目して研究を進め、この結晶化が開始する以前の段階においてメゾスコピックスケール(〜10nm)で密度と配向のゆらぎによる新しい秩序化過程を見い出した。当該年度においては、このメゾスコピックスケールでの新しい秩序形成と高分子の分子レベルでの構造形成を結び付ける目的で重水素化ラベル中性子小角散乱法により、結晶化誘導期における分子鎖形態、特に配向秩序化の鍵となる分子鎖の剛直性(持続長)に着目して研究を進めた。その結果、結晶化誘導期において、分子鎖の持続長が10%程度増大すること、およびその持続長の値が配向秩序化(isotropic-nematic転移)を行うための条件を満たしていることが明らかになった。これは、ガラス状態ではランダムコイルとして存在する分子鎖が結晶化誘導期においてその持続長を増大させるため、排除体積効果により配向秩序化が進行し、分子鎖が平行配向するようになり、この後分子鎖のパッキングが始まり結晶化に進むという我々のモデルを裏付ける結果であった。さらに、この誘導期における持続長の増大は、分子鎖のゴ-シュ形からトランス形へのコンフォメーション変化が原因だと考え、DSC(示差熱分析)と赤外吸収分光の同時測定によりトランスコンフォメーションが誘導期において増大していることを直接的に明らかにした。これらの研究により、高分子の結晶化においては従来考慮されていなかった配向と密度の2つのオーダーパラメーターが重要な働きをしてメゾスコッピクな秩序化を進めることおよびその分子論的起源が明らかになった。

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Social Activities 8

  1. 宮城県古川高等学校 大学出前講座

    2015/11/06 -

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    「物質から生命へ」のタイトルで授業を２回行った。

  2. 第３０回湯川記念講演会

    2014/10/12 -

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    「物質から生命への道」のタイトルで一般向け講演会を行った

  3. 平成２６年度宮城県高等学校理科研究会大崎支部講演会

    2014/09/11 -

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    「物質から生命へ」のタイトルで理科教師向けに講演を行った

  4. 大阪大学 最先端の物理を高校生に

    2013/11/02 -

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    主に近畿地方の高校生を対象に最先端の物理を高校生にわかりやすく解説する。生命への物理からのアプローチというタイトルで講演した。

  5. 岩手県立花巻北高等学校進路講演会

    2013/06/04 -

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    最近の物理研究の一端を高校生にわかりやすく紹介し、進路選択の際の参考にしてもらう。

  6. 東北地区高等学校物理教育研究会

    2013/01/19 -

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    東北地区高等学校の物理教師に最近の物理の研究の一端を紹介する

  7. 大阪大学 最先端の物理を高校生に

    2012/10/20 -

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    大阪大学が大阪府、京都府、兵庫県、奈良県の教育委員会の後援をうけて、高校生に最新の物理を毎週土曜日に６日間伝える。その中の生命物理に関する講義を担当。

  8. 大阪大学 最先端の物理を高校生に

    2011/11/05 -

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    大阪大学が大阪府、京都府、兵庫県、奈良県の教育委員会の後援をうけて、高校生に最新の物理を毎週土曜日に６日間伝える。その中の生命物理に関する講義を担当。

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Media Coverage 2

  1. 微小カプセル 冷却で薬剤放出

    日経産業新聞

    2012/02/28

    Type: Newspaper, magazine

  2. お茶の水女子大、冷やすと内部薬剤を放出するカプセル粒子を開発

    日刊工業新聞

    2011/12/05

    Type: Newspaper, magazine

Other 7

  1. 分子供給系を持つ自己生産ベシクルの開発

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    両親媒性分子が作る球状の閉じた２分子膜構造はベシクルと呼ばれ、有機物質が生命へと進化を遂げる際に、最初にできた分子集合体だと考えられている。このベシクルは、様々な化学物質と相互作用することにより、自己生産・膜輸送・自己駆動などの生命現象に密接な機能を獲得し、自己触媒系と連携して生命へと進化したと考えられている。本研究では、日本でソフトマター物理学を基盤に分子集合体から生命機能の発現機構を研究する我々のグループとスウェーデンの分子集合体の物理化学のリーダーであるLund大学のOlsson教授のグループが連携して、様々な化学物質と相互作用することにより発現するベシクルダイナミクスの物理化学的な起源を明らかにしようとするものである。

  2. 人工膜上での高分子合成による情報分子の創成

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    人工膜上で膜情報を分子構造に取り入れた高分子を合成させ、高分子とベシクルの行動的なダイナミクスを明らかにする。

  3. 変形しながら駆動する分子集合体の物理

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    リン脂質分子に界面活性剤を作用させ、その溶解性を利用してベシクルを変形させながら駆動する分子集合体を開発、その機構を解明する。

  4. 脂肪酸ベシクルを用いた生命機能発現機構の解明

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    脂肪酸ベシクルを用いて最も単純な生命機能であるベシクルの代謝や成長を再現するための基礎研究。

  5. 自己生産ベシクルの物理機構の解明

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    自己生産するベシクルの変形過程を３次元画像解析し、膜弾性理論に基づき、その機構を解明する。

  6. 人工細胞の創成

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    菅原正研究室で進めている人工細胞の生命樹の発現機構を巻く物理の観点から解明する。

  7. 化学刺激によるベシクルの制御

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    ベシクルに様々な化学刺激を与え、その応答ダイナミクスを調べることにより、ベシクルの化学制御を目指す。

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