Butsuri
Online ISSN : 2423-8872
Print ISSN : 0029-0181
ISSN-L : 0029-0181
Volume 71, Issue 11
Displaying 1-27 of 27 articles from this issue
Preface
Contents
70 Challenges and Mysteries in Physics
Trends
Interdisciplinary
  • Hiroyuki Shimada, Akinari Yokoya, Masatoshi Ukai
    Article type: Interdisciplinary
    2016 Volume 71 Issue 11 Pages 736-745
    Published: November 15, 2016
    Released on J-STAGE: August 03, 2017
    JOURNAL FREE ACCESS

    A new spectroscopic research for radiation damage to DNA and related molecules is proposed, which is made possible using a liquid micro-jet technique for bio-solution under vacuum in combination with site-selective excitation using a soft X-ray synchrotron radiation. Described is the present state of research on the selective primary radiation interaction onto base moieties of nucleotides. Spectra of X-ray absorption near edge structure (XANES) at energies around the nitrogen K-edge for nucleotides in aqueous solutions are presented. Selective excitation of a base moiety using a soft X-ray synchrotron radiation allows us to investigate the interaction of the base moiety with water solvent. We discuss the change of spectral character of XANES which reveals to the structural change of the base moiety under different pH condition of solution. A new scope for cooperative direct and indirect primary radiation effets is given.

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Researches
  • Yusuke T. Maeda, Tatsuya Fukuyama
    Article type: Researches
    2016 Volume 71 Issue 11 Pages 746-751
    Published: November 05, 2016
    Released on J-STAGE: August 03, 2017
    JOURNAL FREE ACCESS

    Atoms and molecules move along a gradient of external fields as seen in electrophoresis, which is a motion of charged molecules relative to fluid along an electric field. One unexplored but relevant alternative is thermophoresis, the Ludwig-Soret effect, that makes a solute moves along a temperature gradient. Thermophoresis depletes a polyethylene (PEG) polymer of large concentrations from the hot region and builds a concentration gradient. In such a solution, solutes of small concentration experience thermophoresis and PEG concentration-dependent restoring forces. Under focused laser heating, DNA and RNA as solutes localize as a ring-like structure which diameter monotonically decreases with the size of polymer following a behavior analogous to gel electrophoresis. Thus trapping and separation of biopolymers could be physically feasible in a simple way relying on temperature gradient. Moreover, since this effect relies on the entropic force in a PEG concentration gradient, trapping with little material dependence is feasible for bacteria and motile eukaryotic cells. It may bring new method to control the density of living cells and biopolymers with light.

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  • Yasuyuki Hatsuda
    Article type: Researches
    2016 Volume 71 Issue 11 Pages 752-756
    Published: November 05, 2016
    Released on J-STAGE: August 03, 2017
    JOURNAL FREE ACCESS

    It is known that topological string theory is related to integrable systems. This fact allows us to solve an integrable system by using results in the corresponding topological string. We show that the eigenvalue problem for a class of quantum integrable systems, including the relativistic Toda lattice, is indeed solved by the topological strings. It turns out that the obtained quantization conditions have a non-trivial strong-weak duality with respect to the Planck constant.

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  • Yuichiro Matsuzaki
    Article type: Researches
    2016 Volume 71 Issue 11 Pages 757-761
    Published: November 05, 2016
    Released on J-STAGE: August 03, 2017
    JOURNAL FREE ACCESS

    Here, we have studied the performance of an entanglement sensor under the effect of non-Markovian dephasing that is the dominant source of decoherence in solid-state systems. We have shown that one can actually sense a magnetic field with an accuracy far beyond the classical limit in realistic conditions. Our scheme could pave the way to realize a practical entanglement sensor.

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  • Hideyuki Hotta
    Article type: Researches
    2016 Volume 71 Issue 11 Pages 762-766
    Published: November 15, 2016
    Released on J-STAGE: August 03, 2017
    JOURNAL FREE ACCESS

    Recent advances about the 11-year sunspot cycle is reviewed especially using numerical calculations. The main issue is generation of ordered large-scale magnetic field from chaotic small-scale flows and magnetic fields.

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