Disulfide bonds are stable at room temperature, while their exchange reactions are caused with mild heating. A methacryl resin-based photo-adhesive material containing disulfide bonds were developed for adhesion between some dissimilar substrates. This material would be also utilized for reuse of the adhesive layers themselves as well as the substrates. A bi-functional methacryl monomer having a disulfide bond was designed and synthesized in a 21% yield. This monomer was used in a radical UV curing system, to obtain ca. 6 MPa of shear stress after 1 J/cm2 of UV irradiation at a wavelength of 365 nm. It was found that a glass-glass photo-adhesive sample was thermally dismantled at 55oC, while complete cohesive failure was not observed. A preliminary re-adhesion test was then performed with corresponding UV-cured films, suggesting that disulfide bonds would contribute to fuse two films at their interfaces in molecular level.

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The fundamental optical properties and devitrification process were studied in the glasses of the BaO-B2O3-TiO2 ternary system.The transmittance spectra, refractive index and dispersion show that the glasses have favorable optical properties comparable to the conventional optical glasses. The thermal stability of the glasses was also estimated by the XRD measurements in the glasses heat-treated for the crystallization. The alumina crucible was used to estimate the influence of the alumina contamination in the practical glass fabrication process. It is supposed that the alumina contamination does not induce the obvious degradation of the optical properties and thermal stability in these glasses.

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This paper considers the public nature of language. Should we assume that a speaker's language can be understood by anyone who has sufficient evidence and rationality ? Or should we assume that it need not necessarily be understood by everyone, but only by those who share conceptual scheme? This question connects to the question of intelligibility of the idea of different conceptual schemes. And the question of the intelligibility of different conceptual schemes ultimately leads to the question of whether intelligibility requires epistemic conditions. The argument considered in this paper is based on the fact that concepts such as language and truth are theoretical concepts. And it is made clear that, at least in that argument, it does not follow that epistemic conditions are required.

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This study discusses the applicability of task-based language teaching (TBLT) at the National Institute of Technology(KOSEN). It starts with a brief introduction of TBLT, referring to a definition of task and TBLT, the distinction between TBLT and task-supported language teaching, and the concept of needs analysis. Subsequently, it discusses the suitability of TBLT at KOSEN, emphasizing that TBLT aligns well with English education at KOSEN due to its compatibility with designing a curriculum for engineers and KOSEN students’ perceived needs, its minimal influence on entrance examinations, and the fact that it requires no fixed textbooks. Thereafter, it discusses potential issues of introducing TBLT at KOSEN, which encompass limited opportunities for teacher training, a lack of task materials for KOSEN students, and dealing with diverse classroom constraints. Finally, this study suggests the necessity for more research in the context of KOSEN, emphasizing the importance of a systematic evaluation of TBLT at both the classroom and program levels.

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On 5 May 2023, a magnitude 6.5 earthquake struck the coast of Ishikawa Prefecture, Japan. The earthquake caused 48 human casualties and damage to 1,685 houses. This report presents a summary of the earthquake and geotechnical damage, based on field surveys conducted immediately after the earthquake as well as information collected by local government and the mass media. As a result, the causes of damage to houses and water outages, and the characteristics of the earthquake ground motion are shown. In addition, the outline of damage caused by the ground failure, such as road closures, slope failures, and liquefaction, is clarified.

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