Publications by authors named "Koichiro Shirota"
Article Synopsis
- The study examines the response of a specific subphase in a binary liquid crystal mixture when subjected to an electric field, utilizing specially aligned cells.
- In the antiferroelectric phases, distortions in the structure induce polarization that aligns with the electric field, but in the 1/2 subphase, the structure initially resists deformation, leading to a significant change in optical properties at low electric field strengths.
- The findings suggest that thermal fluctuations are crucial in facilitating a reorientation of the liquid crystal structure, contributing to a unique switching behavior seen in certain liquid crystal displays.
Sphingomyelin (SM) is a major sphingolipid in mammalian cells that forms specific lipid domains in combination with cholesterol (Chol). Using molecular-dynamics simulation and density functional theory calculation, we identified a characteristic Raman band of SM at ∼1643 cm(-1) as amide I of the SM cluster. Experimental results indicate that this band is sensitive to the hydration of SM and the presence of Chol.
View Article and Find Full Text PDFInfrared (IR) and Raman spectra of a sphingomyelin (SM) bilayer have been calculated for the amide I, II and A modes and the double-bonded CC stretching mode by a weight averaged approach, based on an all-atom molecular dynamics (MD) simulation and a vibrational structure calculation. Representative structures and statistical weights of SM clusters connected by hydrogen bonds (HBs) are observed in MD trajectories. After constructing smaller fragments from the SM clusters, the vibrational spectra of the target modes were calculated by normal mode analysis with a correction for anharmonicity, using density functional theory.
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