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Overwritten magnetization at the off-track position is studied by using micro-magnetic simulation employing the Landau-Lifshitz-Gilbert equation. The nominal track width was 600 nm and bit length was 100 nm. The first bit of overwritten magnetization at large off-track distances more than 50 nm is connected with the third bit at high frequencies. This is due to the decrease of the head field at the edge. The magnetization of the track edge is not quite reversed after completing overwrite. As the frequency increases, the head field decreases due to rise-time effects, so that overwrite cannot be completed normally. An increase in the resistivity of the head core material is useful in order to improve the off-track overwrite characteristics. Index Terms--Computational micromagnetics, high frequency recording, off-track, overwrite, resistivity of the head.

We study the dynamic recording process due to the write head driven by high frequency signal currents. Magnetizations of medium recorded with fields at several frequencies from 100MHz to 500MHz are calculated by using Landau-Lifshitz-Gilbert equation. As the frequency increases, the normalized rise time of the head field increases proportionally. The bit shift becomes large at high frequencies due to the delay. The peak value of the head field decreases with the delay, so that the magnetization reversal cannot occur at high frequencies. The saturation magnetic flux density of the head tip is almost independent on the rise time. So, the peak value of the head field does not increase at frequencies more than 400MHz as the saturation flux density increases.

An anomalously large dielectric permittivity of ≈10 4 is found in the mesophase temperature range (MP phase) wherein high fluidity is observed for a liquid-crystal compound having a 1,3-dioxane unit in the mesogenic core (DIO). In this temperature range, no sharp X-ray diffraction peak is observed at both small and wide Bragg angles, similar to that for a nematic phase; however, an inhomogeneous sandy texture or broken Schlieren one is observed via polarizing optical microscopy, unlike that for a conventional nematic phase. DIO exhibits polarization switching with a large polarization value, i.e., P = 4.4 µC cm -2 , and a parallelogram-shaped polarization-electric field hysteresis loop in the MP phase. The inhomogeneously aligned DIO in the absence of an electric field adopts a uniform orientation along an applied electric field when field-induced polarization switching occurs. Furthermore, sufficiently larger second-harmonic generation is observed for DIO in the MP phase. Second-harmonic-generation interferometry clearly shows that the sense of polarization is inverted when the +/- sign of the applied electric field in MP is reversed. These results suggest that a unidirectional, ferroelectric-like parallel polar arrangement of the molecules is generated along the director in the MP phase., (© 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The first example of the control of porphyrinoid chromophore symmetry based on the positional isomerism of peripheral substituents has been achieved by preparing tetraazaporphyrins (TAPs) with C(4h), D(2h), C(2v), and C(s) symmetry due to the relative arrangement of peripheral tert-butylamino and cyano groups as push and pull substituents, respectively. The four structural isomers were successfully isolated and characterized by (1)H NMR spectroscopy and X-ray crystallography. The band morphology in the Q-band region varies depending on the molecular symmetry due to the significant perturbation introduced into the chromophore by the push and pull substituents. The C(4h) and C(2v) isomers exhibit a single Q band, whereas the Q bands of the D(2h) and C(s) isomers show a marked splitting. The magnetic circular dichroism spectra indicate that the push-pull TAPs retain the properties of the 16-membered 18π-electron perimeter generally observed for porphyrinoids. Theoretical calculations have demonstrated that the perturbation introduced by the substituents lowers the D(4h) symmetry of the parent TAP π-conjugated system, and this results in significant spectral changes. A novel approach to the fine-tuning of the spectral properties of porphyrinoids based on changes in the chromophore symmetry is described., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

In this study we investigated the attitudes of Japanese medical students toward being informed of a diagnosis of life-threatening illness. Fourth-year medical students from 20 randomly sampled universities were administered questionnaires that examined their opinion about whether they would welcome disclosure of medical information if they were diagnosed as having an ultimately fatal disease. Data from 1,619 students (male 1,074, female 545, effective collection rate 90.6%) were analyzed. With regard to attitudes about disclosure of a diagnosis of life-threatening illness, 87.7% of the students stated that they would wish to be informed even if there was little chance of recovery, and 11.6% expressed a wish to be informed of their condition only if there was a chance of recovery. Students who did not wish to be informed even if there was a chance of recovery accounted for 0.7% of those surveyed. Our study reveals that medical students are more positive than are members of the general population with regard to being informed of the truth. The proportion of those who wished to be informed even if there was little chance of recovery was higher among students from national and public universities than among those from private universities, and the inter-group difference was statistically significant. Among male students, answers to the survey were significantly correlated with 12-item General Health Questionnaire scores and mental health status, suggesting that mental health status may have affected how this study population viewed being informed of their diagnosis.