In classical guitar, playing technique affects the tone and expression. The results of FFT(Fast Fourier Transform) analysis and calculation of overtone content rate showed that the fundamental tone is emphasized in the apoyando technique, while the overtones are more abundant in the al-aire technique. In addition, the overtones were divided into consonant interval components and dissonant interval components, and the consonant interval factor was calculated to evaluate the balanc e between the two components. The results showed that the al-aire technique had higher factor. We believe that scientific clarification of the difference in tone between the al-aire technique and the apoyando technique will enable more effective improvement of tone.

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The measles virus is a highly contagious pathogen responsible for causing measles, for which no effective treatment is currently available. Consequently, the development of therapeutic drugs remains a pressing need. Recently, inhibitors targeting the measles virus fusion protein—a critical factor in the virus's pathogenicity—have been identified and are considered promising candidates for therapeutic drug development. In this study, we employed fragment molecular orbital (FMO) calculations to elucidate the interaction mechanism between AS-48, a representative inhibitor, and the fusion protein.

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The development of efficient hydrogen recovery methods for fusion reactor divertor materials is key to their long-term stability. In this work, a novel hydrogen recovery technique using solid-state diffusion was investigated, focusing on the intrinsic hydrogen solubility properties of metals.A tungsten (W) substrate was coated with a Niobium (Nb) thin film by ion plating, followed by Deuterium plasma irradiation under ITER-relevant conditions (fluence: 5.3×10²⁶ /m²). The structural evolution was evaluated by analysing the changes in lattice constants using X-ray diffraction (XRD).The results showed lattice expansion in the W substrate and unexpected contraction in the Nb thin film. This behaviour is attributed to the supersaturation of hydrogen in the W substrate, generating tensile stress in the confined Nb film due to volume expansion. The observed structural changes extended throughout the 1 mm thick substrate, suggesting significant hydrogen transport.These results indicate that while hydrogen permeation into Nb is thermodynamically favourable, the mechanical interaction between substrate and film must be carefully controlled. This work provides important insights for the design of effective hydrogen recovery systems in fusion reactor environments.

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Avian influenza is a disease that primarily affects birds but is rarely transmitted to humans. The fatality rate of infection with the highly pathogenic H5N1 avian influenza virus is particularly high. Oseltamivir is known to be an effective antiviral agent against both human and avian influenza. However, an Asn-to-Ser mutation in the N1 neuraminidase has been reported to confer resistance to oseltamivir, and accurate analysis to identify the cause of drug resistance is needed. In this study, fragment molecular orbital (FMO) calculations were performed to gain insight into the electronic mechanism of oseltamivir resistance in avian influenza neuraminidase. The FMO method is an innovative approach that enables quantum mechanical calculations of entire biomolecules, such as proteins. The amino acid residues involved in ligand binding can be identified through the interfragment interaction energies (IFIEs) derived from FMO calculations. The IFIE results suggest that one of the factors contributing to oseltamivir resistance in the N294S mutant is a reduction in the interaction energy between oseltamivir and ASP151, ARG152, and GLU277 in the N1 mutant. The Asn-to-Ser mutation at position 294 does not directly have a significant impact.

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