In this study we investigated the effects of underwater exercise in warm water (34 degrees C) on physiological and psychological relaxation. Eight healthy young men (aged 20-26 years) volunteered for the experiment. The experiment consisted of the following three successive segments: a pre-exercise period of 20 min, during which the subjects rested in a semi-supine posture with their eyes closed for the final 10 min; an underwater exercise period of approximately 60 min, during which the subjects performed gymnastic exercises or aerobic dancing with occasional movements or jumping; a post-exercise recovery of 20 min, which was similar to the pre-exercise rest period. We compared the relative power values (power %) of the electroencephalogram alpha bands (8-13 Hz) and profile of moods states (POMS) before and after the underwater exercise. We also estimated the percentage of maximal heart rate (%HRmax) throughout the experiment to ascertain the intensity of the underwater exercise. The results of %HRmax indicated that the intensity of underwater exercises practised in the experiments ranged from low to moderate. The power % of EEG alpha bands had increased significantly after the underwater exercise compared with the pre-exercise rest (P<0.05). From the POMS results, we observed that positive mood (vigour) increased and negative mood (tension and anxiety, depression and dejection) decreased significantly after the underwater exercise (P<0.05). This study found that the subjects showed increased physiological and psychological indices of relaxation after underwater exercise.

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In this work, polarized pump-probe spectroscopy was carried out to investigate the effects of a structural ordering of molecules on photoinduced phase separation (PIPS) in the organic conductors κ-(BEDT-TTF) 2 X [X = Cu[N(CN) 2 ]Br (κ-Br) and Cu(NCS) 2 (κ-NCS)]. We found that the anisotropic response for the probe polarization appeared at around T g , where the glasslike structural transition occurs. The anisotropy can be a result of a transient destruction of the local ordering of molecules, indicating a connection between the glasslike transition and PIPS. Moreover, we found that the PIPS response gradually develops with decreasing temperature in κ-Br, whereas it steeply increases in κ-NCS. This qualitative difference suggests that the structural ordering caused by a PIPS is more crucial in κ-NCS than in κ-Br.

To determine whether there is a direct correlation between endurance capacity and cold tolerance, maximal oxygen consumption (VO2max), and cold-induced vasodilatation (CIVD), we measured these factors in 14 young female athletes born in Hokkaido, Japan's northernmost island. We determined the VO2max by a standard incremental test on a cycle ergometer and measured the oxygen consumption (VO2) by means of the Douglas-bag method. We determined the CIVD reaction by measuring the skin temperature of the left middle finger during immersion in cold water at 0 degree C for 20 min. The athletes showed significant positive correlations between VO2max, expressed as 1/min, and CIVD as well as other peripheral cold tolerance indexes (resistance index against frostbite and CIVD index). The body weight VO2max (VO2max/kg body weight) failed to correlate significantly with either the CIVD or with other cold tolerance indexes. These results suggest that CIVD in females may depend on factors other than those determined in this study, in addition to the functional spread of the vascular beds in peripheral tissues, including striated muscle; it is known that the size and the vascular bed in this tissue are affected by exercise training and that this results in the elevation of VO2max and VO2max/kg body weight.

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In this work, polarized time-resolved spectroscopy was carried out to investigate a superconducting (SC) state of the organic compounds κ-(BEDT-TTF)2X (X=Cu(NCS)2 (κ-NCS, Tc ∼ 9 K) and Cu[N(CN)2]Br (κ-Br, Tc ∼ 12 K)), which have different effective electron correlations. We found that the SC response, which was characterized by probe polarization anisotropy with slow relaxation time, decreases steeply at approximately Tc in κ-NCS with increasing temperature, corresponding to the closing of the SC gap. On the other hand, in κ-Br the SC response persisted significantly above Tc. The results indicate that fluctuating superconductivity (FSC) emerges in κ-Br but not in κ-NCS, suggesting that strong electron correlation can play a critical role for FSC. * * * We would like to thank T. Mertelj, D. Mihailovic and K. Ichimura for valuable discussions. This work was supported by JSPS KAKENHI Grant No. 15K17685.

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We investigated photo-excited carrier relaxation dynamics in the strongly correlated organic superconductors κ-(BEDT-TTF) 2 Cu(NCS) 2 and κ-(BEDT-TTF) 2 Cu[N(CN) 2 ]Br, using different polarizations of pump and probe pulses. Below the glasslike transition temperature (T g ) anisotropic responses for probe polarization were observed in both compounds. Decomposing the data into anisotropic and isotropic components, we found the anisotropic component shows no pump polarization dependence, meaning that dissipative excitation process was dominant for the anisotropic carrier relaxation. This behavior indicates that the appearance of anisotropic responses can be associated with spatial symmetry breaking due to structural change of BEDT-TTF molecules.