Liquids confined in molecular-scale spaces show remarkably different properties from those of the bulk state due to the spatial limitation and the interactions between the liquid molecules and solid surfaces. We have developed the resonance shear measurement (RSM) based on the surface forces apparatus (SFA) and applied it for evaluating the viscosity and lubricity of confined liquids. This method utilizes the resonance signal of the top mechanical unit that sensitively changes depending on the properties of the confined liquids, offering a method with high sensitivity and stability. This article reviews the principle of RSM and applications of the measurement for tribology by providing examples of water between silica surfaces and pheny ether lubricants between mica. The future use of the measurement is described.

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Great attention has been paid to molecular dynamics of drug deliveries to lipid bilayer membranes as a primary stage of bioactivities in the cell. Lipid bilayer membranes are dynamic structures where molecules are moving and fluctuating under physiological conditions. Thus the mechanisms of drug deliveries are considered to be relevant to such dynamics in soft, fluid membrane interface. To gain insight into molecular motions and fluctuations in membranes, methods are critical factors to be developed. In this review, a noninvasive strategy to monitor dynamic properties of drugs and lipid membranes is introduced. By applying multinuclear high-resolution solution NMR in combination with the pulsed-field-gradient (PFG) technique, dynamic aspects of drug deliveries have been quantified without undesirable perturbation of the system. Special focus is on how much and how fast drugs are bound to the membrane, and how fast drugs are moving within the membrane in situ by using lipid bilayer vesicles as model cell membranes. An anticancer 5-fluorouracil, a fluorinated derivative of an endocrine disruptor, bisphenol A, a neuropeptide enkephalin, and an anesthetic sevoflurane are compared as a model drug. The effect of cholesterol on deliveries is also discussed in relation to the dynamics in membranes.

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Have you ever hoped to observe the transition states? Phenomena which are too fast to be directly observed by our eye, can be visualized by observing them using strobe lights. The use of such stroboscopic method to observe ultrafast chemical bond breaking and formation in chemical reactions has been a long-awaited dream for chemists. Using pulse laser whose duration is much shorter than the molecular vibrational periods, molecular motion in those vibrational modes can be time-resolved observing the modulation of transition probability of the corresponding wavelength in real-time. Molecular structural changes during photoreaction via transition states can be observed by real-time vibrational spectroscopy using visible 5-fs pulse laser. Meanwhile, transition states in thermal reactions still could not be studied because the general femtosecond pulse laser cannot trigger chemical reaction in the electronic ground state. In the present work, visible ultrashort pulse laser caused induced Raman process to excite Raman active molecular vibrational modes in the electronic ground states, which triggers the reaction induced by coherent molecular vibrational excitation in the electronic ground state just after photoexcitation. Using the “reaction by coherent molecular vibration”, the transition states in a thermal reaction was also observed.

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Water-soluble materials of fullerenes (C₆₀, C₇₀, M₃N@C₈₀) were prepared by complexation or derivatization in combination with water-soluble polymers such as poly (vinylpyrrolidone) (PVP) and polyethylene glycol (PEG). Prepared fullerene materials had enough solubility in water to subject to several biological in vitro tests. The generation of reactive oxygen species (ROS) was confirmed mainly by electron spin resonance (ESR) method in the presence of spin-trapping agents.

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Our previous work showed that the critical micelle concentration (CMC) of dodecanoyloxymethyl-18-crown-6 (C11Φ6) in the presence of 0.22 mol kg^-1 alkali metal ion was the highest for K⁺ having an ionic diameter comparable to the hole size of 18-crown-6 ring and decreased as an ionic diameter of added cation departed from the hole size. In this study, we used octanoyloxymethyl-18-crown-6 (C7Φ6) having the higher CMC than C11Φ6, measured electric conductivities of aqueous C7Φ6 solutions in the presence of alkali metal ions and evaluated stability constants of C7Φ6/alkali metal ion complexes to confirm that the dependence of CMC of crown ether surfactant on the ionic diameter of alkali metal ion is attributed to the selective cation inclusion of its crown ring. As a result, it was found that the stability constant of C7Φ6/alkali metal ion complex was the largest for K⁺ and decreased as a diameter of cation departed from the hole size as expected. C7Φ6 exhibited the larger stability constant and the lower cation selectivity than 18-crown-6, suggesting that the oxygen atom of carbonyl group in joint part between crown ring and alkyl chain of C7Φ6 participates in the complexation with alkali metal ion.

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The Society of Japanese women scientists is working on science faculty going promotion for female junior and senior high school students by cooperation with the Gender Equality Bureau Cabinet Office. In this activity, we pay an attention that they have clear bias towards biology and life science even in science fields. They show a quite low interest in technology field. This bias will resulted in limited fields in which female researchers play active parts.
There is a statement which mentions inherent sex difference between male and female about the origin of this bias. However, few role models of female researchers in technology field can raise the poorness of the introduction towards female junior and senior high school students. In order to advance the promotion effectively, we need development of the methodology which enlightens wide going field choice.
On the other hand, proposal of gendered innovation is watched about the bias based on gender difference.

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