Methanol oxidation reaction (MOR) has been investigated at sputtered Pt−Ru, Ru, and Pt electrodes by using in-situ FTIR spectroscopy with the attenuated total reflection technique (ATR), which can identify species adsorbed on the electrode surface. Linear CO, bridged CO, and COO- were detected as the intermediates in the MOR. The electro-oxidation of preadsorbed CO was also studied to clarify the mechanism of the MOR at these electrodes. Water molecules coadsorbed with CO were clearly detected at Pt−Ru and Ru electrodes at less positive potential region below the onset potential of ca. 400 mV vs RHE for the electro-oxidation of both methanol and preadsorbed CO. The IR-band intensities of both the adsorbed CO and water commenced to decrease simultaneously at ca. 400 mV on Pt−Ru alloy, demonstrating that the adsorbed CO is oxidized by consuming the adsorbed water. The pure Ru electrode exhibited a high activity for the oxidation of preadsorbed CO, but showed a low activity for the MOR due to the slow dehydrogenation adsorption of the methanol. It is clarified that Pt sites on the alloy surface dehydrogenate methanol and form CO dominantly while Ru sites adsorb water molecules preferentially as oxygen-species needed for the CO oxidation, presumably involved as Ru−OH formed by discharging the adsorbed water. These results support the “bifunctional mechanism” at Pt−Ru alloy for the oxidation of methanol and CO.

Methanol oxidation has been investigated at a sputtered Pt film electrode by using in situ Fourier transform infrared spectroscopy with the attenuated total reflection technique, which can identify directly adsorbed species on the electrode surface. Linear CO, bridged CO, formyl species, and formic acid-related species have been clearly identified during the electro-oxidation of methanol in the intact cyclic voltammogram between 0.05 and 1.0 V, where the initial potential is applied at 0.05 or 1.0 V. The formyl species, linear CO, and bridged CO adsorb on the Pt surface at a low potential, for example, 0.05 V. A potential-induced conversion between the linear CO, the bridged CO, and the formic acid-related species is observed during the methanol oxidation. It was clear that an oxidation via formic acid, at least up to formic acid, is the predominant route for the methanol oxidation in a potential range from 0.2 V to ca. 0.6 V and the oxidation is prohibited by the high coverage of Pt sites with CO. In a higher potential region than that, the CO and HCOOH parallel routes are opened for the complete methanol oxidation. The correlation between the methanol oxidation and the oxides formed on Pt surface is also discussed, which affects the reactivity of the electrode and the reaction mechanism.

Adsorbed water molecules which promote the methanol oxidation reaction (MOR) at Pt-Ru alloy electrode are clearly detected by in-situ FTIR spectroscopy with the attenuated total reflection configuration, which directly supports the "bi-functional mechanism" for the MOR.

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The seismic ray theory in anisotropic inhomogeneous media is studied based on nonEuclidean geometry called Finsler geometry. For a two-dimensional ray path, the seismic wavefront in anisotropic media can be geometrically expressed by Finslerian parameters. By using elasticity constants of a real rock, the Finslerian parameters are estimated from a wavefront propagating in the rock. As a result, the anisotropic parameters indicate that the shape of wavefront is expressed not by a circle but by a convex curve called a superellipse. This deviation from the circle as an isotropic wavefront can be characterized by a roughness of wavefront. The roughness parameter of the real rock shows that the shape of the wavefront is expressed by a fractal curve. From an orthogonality of the wavefront and the ray, the seismic wavefront in anisotropic media relates to a fractal structure of the ray path.

Immunohistochemistry for two nociceptive transducers, the transient receptor potential cation channel subfamily V members 1 (TRPV1) and 2 (TRPV2), was performed on the pharynx and its adjacent regions. TRPV1-immunoreactivity (IR) was detected in nerve fibers beneath and within the epithelium and/or taste bud-like structure. In the pharynx, these nerve fibers were abundant in the naso-oral part and at the border region of naso-oral and laryngeal parts. They were also numerous on the laryngeal side of the epiglottis and in the soft palate. TRPV2-IR was expressed by dendritic cells in the pharynx and epiglottis, as well as in the root of the tongue and soft palate. These cells were located in the epithelium and lamina propria. TRPV2-immunoreactive (IR) dendritic cells were numerous in the naso-oral part of the pharynx, epiglottis, and tongue. Abundance of TRPV2-IR dendritic processes usually obscured the presence of TRPV2-IR nerve fibers in these portions. However, some TRPV2-IR nerve fibers could be observed in the epithelium of the soft palate. Retrograde tracing method also revealed that sensory neurons which innervate the pharynx or soft palate were abundant in the jugular-petrosal ganglion complex and relatively rare in the nodose ganglion. In the jugular-petrosal ganglion complex, TRPV1- and TRPV2-IR were expressed by one-third of pharyngeal and soft palate neurons. TRPV2-IR was also detected in 11.5 % pharyngeal and 30.9 % soft palate neurons in the complex. Coexpression of TRPV1 and CGRP was frequent among pharyngeal and soft palate neurons. The present study suggests that TRPV1- and TRPV2-IR jugular-petrosal neurons may be associated with the regulation of the swallowing reflex.

The Earth's magnetic field undergoes aperiodical reversals. These can be explained by a simple two-disc dynamo system (Rikitake system). In this paper, the Rikitake system is studied based on a differential geometry (theory of Kosambi–Cartan–Chern). The electrical and mechanical equations of motion are derived from Faraday's law as well as from magnetohydrodynamic equations. From the geometric theory, the solution of the Rikitake system can be regarded as a trajectory on the tangent bundle. Accordingly, there exist five geometrical invariants in the Rikitake system. The third invariant as a torsion tensor can be expressed by mutual-inductances as a result of electrical and mechanical interactions which cause the aperiodic magnetic reversal. This aperiodic behaviour corresponds to a magnetohydrodynamic turbulent motion by a topological invariant such as Chern–Simons number which expresses the interaction between the toroidal and poloidal currents. This Rikitake system is equivalent to other nonlinear dynamical systems. Thus, chaotic behaviours of various nonlinear dynamical systems can be uniformly investigated by the five geometrical invariants and the topological invariant (the Chern–Simons number).

The Jacobi stability of the normal form of typical bifurcations in one-dimensional dynamical systems is analyzed by introducing the concept of the production process (time-like potential) to KCC theory. This KCC theory approach shows that the geometric invariants of the system characterize the nonequilibrium dynamics of the bifurcations. For example, the deviation curvature that is one of the geometric invariants shows that the well-known two hysteresis jumps in subcritical pitchfork bifurcations differ qualitatively from each other. In the nonequilibrium region, the deviation curvature in the saddle-node and the transcritical bifurcations are a function of the bifurcation parameter alone; thus, the Jacobi stability does not depend on time. However, the deviation curvature in a pitchfork bifurcation is a function of the time-like potential, so the Jacobi stability does depend on time. This time dependence can be described by the Douglas tensor, which is a useful geometric invariant to consider how the higher-order term in the bifurcation system affects the stability structure.