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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Gene sequence-alignment is an important technique in the research field of bioinformatics, providing a fundamental approach to elucidating the structure and function of organisms and their evolutionary relationships. This method enables the correct assessment of the similarity of gene sequences between organisms. On the other hand, information processing to obtain optimal alignment results is NP-complete problem and requires huge computational resources when processing large sequence data. Quantum computation has the potential to provide an innovative approach to this type of problem. In this paper, we propose an alignment method using quantum annealing, an effective computational technique of quantum computing for combinatorial optimization problems, and report the results of validating its effectiveness on computer simulations.

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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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The bioavailability and therapeutic effectiveness of BCS Class II anticancer drugs, such as erlotinib (ERL), are limited by poor solubility. Amorphous solid dispersion (ASD) is an innovative formulation technique to enhance dissolution, solubility, and pharmacokinetic profiles. Erlotinib, a tyrosine kinase inhibitor with limited solubility, was transformed into an amorphous state using solvent evaporation with polymers like polyvinylpyrrolidone (PVP) and polyethylene glycol (PEG). Analytical techniques including FTIR, UV-vis spectroscopy, XRD, DSC, and dielectric spectroscopy confirmed the transition and highlighted polymer effects on drug properties. Dielectric studies revealed a single α-relaxation in ERL+PVP, but dual α-relaxations in ERL+PEG+PVP ASDs. β-relaxation appeared in the glassy states of ERL+PEG and ERL+PEG+PVP. Molecular dynamics simulations showed ERL+PEG is a fragile glass former, while ERL+PVP and ERL+PEG+PVP are strong glass formers, influenced by hydrogen bonding and molecular mobility. ASDs improved solubility, stability, and biological performance, enhancing antioxidant and antiproliferative properties. ERL+PEG ASD significantly inhibited DLA-induced tumor growth in mice, achieving a 98.78 ± 0.3% reduction. These findings demonstrate the potential of polymer-based amorphization strategies to optimize drug delivery and therapeutic efficacy.

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Chronic obstructive pulmonary disease (COPD) is a leading cause of death worldwide and has a high prevalence in Japan. The Ministry of Health, Labour and Welfare has set a goal to reduce COPD-related mortality under the “Healthy Japan 21 (Phase 3)” initiative. In the home healthcare of patients with severe COPD, the combined use of home mechanical ventilation (HMV) and home oxygen therapy (HOT) is common; however, a decline in FiO₂ remains a challenge. This study compared liquid oxygen (LO) and oxygen concentrators (OC), demonstrating that LO can maintain higher FiO₂ levels. In the comparison of oxygen delivery devices, LEGEND AIR showed superior performance compared to other ventilatory devices.

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Y₂O₃:Eu³⁺ phosphors are utilized as UV-excited red emitting phosphors. Blue LEDs emit light at a wavelength around 460 nm, and Y₂O₃:Eu³⁺ shows a slight fluorescence emission due to blue excitation by direct excitation of Eu3+. In this study, RE2O3:Eu³⁺ (RE= Y,La,Gd,Lu) was prepared based on Y₂O₃:Eu³⁺, and the intensity of red emission by blue excitation was investigated. The main phase of the prepared samples was identified as RE₂O₃ by X-ray diffraction measurement, and Y, Gd, and Lu had similar structures, but only La had a different structure. Excitation (Em 613 nm) and fluorescence (Ex 466 nm) spectra showed that Gd₂O₃:Eu³⁺ exhibited higher emission intensity than Y₂O₃:Eu³⁺+, while La₂O₃:Eu³⁺ showed the strongest emission at the longer wavelength of 628 nm. Diffuse reflectance spectra showed that Lu₂O₃:Eu³⁺ and Gd₂O₃:Eu3+ showed stronger blue absorption than Y₂O₃:Eu3+, while La₂O₃:Eu³⁺ changed to the by-product La(OH) ₃ with time, and both emission intensity and absorption decreased. These results indicate that Gd₂O₃:Eu³⁺ is superior to Y₂O₃:Eu³⁺ in blue light absorption and red emission.

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X-ray diffraction (XRD) patterns of hexagonal ice (I_h) and/or stacking-disordered ice (I_sd) have been observed for ice formed in various aqueous systems. Ice I_h and ice I_sd exhibit a diffraction peak at XRD angle of 2θ ≈ 40 deg, but I_h uniquely shows additional peaks at 2θ ≈ 34 deg and 44 deg, which are absent in ice I_sd. We consider that the XRD peak areas at 34, 40, and 44 deg in crystallized aqueous solution can be utilized to estimate the fraction of ice I_h and ice I_sd in crystallized aqueous solutions. To analyze the crystal structure of ice in aqueous solutions, X-ray diffraction measurements of ice formed from pure water as a reference of ice I_h were conducted at 213 K and 188 K at various cooling rates in a range of 0.67 − 150 K/min. Assuming that the ice from pure water is the ice I_h, and variation of the peak areas at 2θ ≈ 34, 40, and 44 deg were evaluated. X-ray diffraction measurements were conducted on crystallized fructose aqueous solutions with fructose concentrations of 20 and 40 wt.%. Based on the results of pure water ice, ice in the fructose aqueous solutions up to 40 wt.% of fructose were identified as ice I_h.

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Domain wall encoding (DWE) is a new computational technique that allows the quantum annealing (QA) to be applied to the continuous variable optimizations. This study verifies by the numerical experiments that the reverse annealing (RA), an auxiliary computational technique of QA, works effectively for QA incorporating DWE and improves the probability of deriving the optimal solution.

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Arterial oxygen saturation (SpO₂) is a non-invasive indicator used to assess the oxygen-carrying capacity of the blood and is widely utilized in conditions such as respiratory failure and hypoxemia. Conventional measurement sites, such as the fingertip and earlobe, have limitations, and nasal measurement has recently gained attention. This study compared the response speed and signal stability between nasal, fingertip, and earlobe measurements using the latest Nasal Alar SpO₂ sensor. The nasal measurement demonstrated stable perfusion index (PI) values and rapid response, proving to be useful even in low perfusion states.

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This study aimed to construct an external fixation model using a cruciate technique that simulates muscle tension under resting and loading conditions during rehabilitation. This model serves as a foundational approach for evaluating the mechanical stability of human ankle joints through strain analysis. Additionally, the feasibility of visualizing strain near the fixation pin insertion site in the cruciate technique model was examined using stereo-DIC, with the goal of identifying mechanical indices for external fixation stability from an experimental mechanical perspective. External fixation often involves inserting the fixation pin obliquely into the bone surface, complicating the adjustment of the camera for accurate imaging. To address this challenge, we experimentally determined a measurement range that minimizes dependence on the stereo-DIC imaging direction. The results demonstrated successful visualization of the principal strain distribution near the fixation pin insertion site in the cruciate technique model using stereo-DIC. However, the maximum principal strain value was found to be influenced by the imaging direction.

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Hydrogen permeable membranes with a cylindrical shape are used in membrane reactors. Systematic investigations have been conducted on hydrogen diffusion coefficients in palladium (Pd) and its alloys. Currently, Pd and its alloys are widely used as hydrogen permeable membranes. Pd-Ag alloy membranes have been reported to exhibit higher permeability and durability than those of Pd. In this work, a cylindrical Pd cell system was constructed, with the inside filled with a pressure-controllable gas and the outside in contact with an electrolyte of an electrochemical cell. Using this system, the hydrogen permeation behavior was evaluated at various temperatures by controlling the temperature of the electrolyte in contact with the entire cylinder. By applying a time-lag method on hydrogen permeation, the hydrogen diffusion coefficient in Pd cylinder at 300.15 K was calculated to be D = 1.7 × 10 ^-10m²/_s , which is considered to be a diffusion coefficient in Pd hydride phase. An additional assessment of hydrogen diffusion coefficients in Pd and Pd-Ag alloy plate specimens was conducted using an electrochemical double-cell equipment also by the time-lag method. In the hydrogen solid solution phase the hydrogen diffusion coefficients of Pd and Pd-Ag alloy plate at 300.15 K were calculated to be D = 1.96 × 10^-11 m²/_s and D = 1.75 × 10^-11 m²/_s, respectively. Comparative analysis with previous studies indicates that the hydride formation mechanism significantly influences both hydrogen diffusion kinetics and overall permeation behavior.

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A fuel cell was characterized by using the impedance measurement method in order to evaluate the proton conduction resistivity (ρ) in the Nafion membrane and the contact resistivity (Q) between the MEA (membrane electrode assembly) surface and carbon block (separater). A non-woven sheet with a squred aperture area was inserted between the MEA surface and the carbon block. The electrical contact area between the MEA surface and the carbon block was varied by changing the aperture area of the non-woven sheet, while the gas supply area was fixed. The series resistance (R _s) of internal impedance of the fuel cell decreased with increasing the aperture area of the non-woven sheet. In this study, an equivalent circuit model of series resistance (R _s) was proposed to evaluate the proton conduction resistivity (ρ) and the contact resistivity (Q). As the result, their values were calculated to be ρ = 8.1 Ωcm and Q = 2.5×10 ^-2 Ωcm ².

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2-nonenal is a volatile chemical component of body odor, known for the correlation between its concentration and the degree of aging. Because the concentration of 2-nonenal changes according to the aging-related metabolism change, measuring 2-nonenal in skin gas has a potential on biochemical evaluation of aging. However, highly selective 2-nonenal sensor has not been developed so far. In this study, we developed a biofluorometric gas sensor (bio-sniffer) that utilize NADPH-dependent enone reductase (ER) for selective detection of 2-nonenal. This sensor detects 2-nonenal by measuring the decrease in autofluorescence of NADPH (ex: 340 nm, fl: 490 nm), which occurs when ER reduces the α, β-unsaturated bond of 2-nonenal. The ER biosensor consists of an ER-immobilized membrane and a fiberoptic NADPH fluorescence detection unit having UV-LED and photomultiplier tube. We evaluated the performance of the ER biosensor using the primary substrate, ethyl vinyl ketone (EVK), and target molecule, 2-nonenal.The selectivity of the ER biosensor on 2-nonenal was also evaluated. The experimental result showed that the ER biosensor can quantify EVK from 100 nM to 1 mM, and it also showed significantly high fluorescence signal on 2-nonenal compared to other aldehydes.

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Continuous measurement of volatile organic compounds is expected for non-invasive monitoring of metabolic functions and screening of diseases. Especially, acetone emitted through the skin is known for its correlation to lipid metabolism and promising for detection of diabetes mellitus. However, the concentration of transdermal acetone is estimated to be sub-ppb level, which requires highly sensitive and selective sensor . Additionally, accurate standard acetone gas at sub-ppb level is also essential for evaluation of these sensors. In our previous study, we developed a biofluorometric acetone gas sensor based on nicotinamide adenine dinucleotide (NADH, excitation 340 nm, emission 490 nm)-dependent secondary alcohol dehydrogenase. In this study, we evaluated the accuracy of concentration of acetone gas at the sub-ppb level, prepared by a flow rate-based continuous dilution method. Then, the reliability of the acetone bio-sniffer was also evaluated by correlation analysis between the signal obtained by gas chromatography-mass spectrometer (GC-MS) and the acetone bio-sniffer at the same acetone gas. The outputs in both measurement methods showed linear correlation (R² = 0.996), indicating the reliability of the acetone bio-sniffer. In the future works, continuous measurement of transdermal acetone at various locations on the body surface will be conducted by using the acetone bio-sniffer.

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