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The soricid water shrew Chimarrogale platycephalus is a mammalian species endemic to the Japanese Islands. The animals inhabit the islands of Honshu and Kyushu, and are considered to be extinct in Shikoku. Information on this water shrew from Honshu and Kyushu is scarce, and C. platycephalus is registered on many local governments' red lists as an endangered species. There are very few studies on their ethology, ecology or phylogenetics, due to difficulties related to the shrews being both nocturnal and aquatic: to study C. platycephalus, field research must be conducted in mountain streams at night. To overcome these challenges, we previously established a genetic analysis method using the feces of C. platycephalus, as a result of which the amount of phylogenetic and phylogeographic data has increased and our understanding of the species has improved. In this study, microsatellite markers were developed, and analyses using markers for 21 loci were performed. Moreover, to confirm the ability of these 21 microsatellite markers to differentiate individuals, all markers were tested using fecal and tissue specimens from 12 individuals reared separately in an aquarium. Using as few as 12 of these loci, individual differentiation with 100% accuracy should be achievable. The development of microsatellite markers in this study and the establishment of individual identification methods should greatly contribute to future ecological, ethological, population genetics and biogeographical research on C. platycephalus.

The soricid water shrew,Chimarrogale platycephalus, is a mammal species endemic to the Japanese Islands. They inhabit the islands of Honshu and Kyushu, and are considered to be extinct in Shikoku. Information on this water shrew from Honshu and Kyushu is also scarce, andC. platycephalusis registered on the Japanese Government’s red list as an endangered species. Almost all study areas such as regarding their ethology, ecology, also their phylogenetics are lacking. The delay in these foundational studies is due to difficulties related to them being both nocturnal and aquatic. In order to study ofC. platycephalus, it is essential to conduct field research in mountain streams at night under such circumstances. In response to such difficult circumstances, we established a genetic analysis method using the feces ofC. platycephalus, and as a result the accumulation of data on their phylogenetic evolution and phylogeography has increased which has improved our understanding of this species. Furthermore in this study, development of microsatellite markers was carried out, and a total of 21 loci marker analyses were performed. In addition, in order to confirm the credibility of these 21 microsatellite markers, as being able to validly differentiate individuals, all markers were examined using the fecal and tissues specimens from verified separately reared individuals (12 individuals) with the known history of having been reared in an aquarium. As a result, it was revealed that if analyses of the 12 loci were possible, individual differentiation with 100% accuracy was possible. The development of microsatellite markers in this study, and the establishment of individual identification methods by means of this will be expected to greatly contribute to future ecological and ethological research, population genetics and biogeographical research of the water shrew,C. platycephalus.

Three-dimensional microstructure observations, macro- to micro-scopic residual stress measurements by three methods and creviced bent beam SCC tests were performed for Inconel/low alloy steel (LAS) weld samples. The possible reasons for the suppression of SCC crack propagation near the weld interface found at a nuclear power plant were estimated to include the crack branching at the grain boundary (GB) parallel to the interface, i.e., Type II GB, compressive residual stresses in the LAS region and crack tip oxidation in the LAS at the interface. The formation mechanism of Type II GB and stress gradient in individual grains in the Inconel are also discussed.

AlxGa1-xN alloys with x=0.375, 0.398, 0.401, 0.592 and 0.696 were deposited on sapphire substrate by the hydride-vapor-phase epitaxy (HVPE) method. Thermal effusivity measurements were carried out on AlxGa1-xN alloys using a thermal microscope at room temperature. The lag between sinusoidal heating laser wave and thermoreflectance wave was used to measure the thermal diffusivity. Thermal conductivity values of the AlxGa1-xN alloys were also obtained as a function of AIN mole fraction in the alloy. The thermal conductivity was found to decrease with increasing AIN fraction and the experimental data agree with values estimated using the virtual crystal model.