Kyushu University

Reducing AC loss in superconducting AC equipment is crucial because of its substantial contribution to the cryogenic load. Decreasing the filament width can mitigate hysteresis loss of REBa ₂ Cu ₃ O _7−δ (REBCO, RE = rare earth elements) superconducting tapes, and segmenting the superconducting layer into multiple filaments is a viable reduction approach. However, filaments tend to connect when the inter-filament resistance is low. Therefore, we propose Cut and Aggregated Multifilamentary (CaAM) tapes with high inter-filament resistance achieved via the electrodeposition of polyimide across the entire tape. This tape configuration involves aligning four 1-mm-wide filaments in parallel and bonding them onto a polyimide substrate. AC loss measurements of short tapes exhibit a reduction at high magnetic fields. Additionally, we fabricated double pancake coils, each coil contained 80×2 turns, wound with monofilament tape and CaAM tape (coils A and B, respectively) and assessed the AC loss of the fabricated coils in liquid nitrogen. Experimental results indicate that the AC loss of coil B, using CaAM tape, is greater than that of coil A in the low-current region. However, they are almost identical in the high-current region. In contrast to the multifilament tapes with low inter-filament resistance, CaAM tapes indicate the possibility of loss reduction when used in coils.

This study focuses on the development of TES (Transition Edge Sensor) microcalorimeters for gamma-ray detection. We developed a position-sensitive TES (PoST) based on our single-pixel TES, constructed from a titanium-gold (Ti/Au) bilayer. The PoST consists of a TES coupled with elongated absorbers to enable position sensitivity. Lead was chosen as the absorber material due to its high stopping power for high-energy gamma rays. However, the thermal contraction mismatch between lead and the TES substrate posed a risk of damage during cooling. To address this issue, we developed a method utilizing serpentine-shaped absorbers, which enables two-dimensional position detection while maintaining the same number of wires as a conventional one-dimensional PoST. The feasibility of this approach was demonstrated with two types of prototype absorbers, and the experimental results are presented below.

Metronomic photodynamic therapy (mPDT) is a method of continuously delivering low-intensity light to a cancer lesion. This approach does not require high-intensity light, enabling the miniaturization of light devices and making them suitable for implantation within the body. However, the application of mPDT to tumors in deep organs such as the liver and pancreas has yet to reach practical implementation. In this study, we developed an mPDT system designed to meet three key requirements deemed essential for practical use: (1) uniform light irradiation throughout the tumor, (2) maintenance of constant light intensity within the body with sufficient operational duration, and (3) avoidance of immunological complications and thermal damage. The newly constructed mPDT system incorporates an ultra-thin organic light-emitting diode (OLED) device and wireless energy transfer technology, allowing it to be designed for implantation in deep organs. In experiments using a rat model of orthotopic hepatoma, the new mPDT system effectively induced widespread cell death deep within the tumor and exhibited high therapeutic efficacy against cancer. This study is the first study to demonstrate that mPDT utilizing a biocompatible and wirelessly powered OLED device has strong anti-tumor effects against parenchymal organ cancers. The findings represent a significant advancement toward the clinical application of mPDT for the treatment of deep organ cancers.

The shiitake fungus moth, Morophagoides moriutii Robinson, 1986 (Lepidoptera: Tineidae) is an important pest in the cultivation of the shiitake mushroom, Lentinula edodes (Berkeley) Pegler. Although (Moriuti, Forest Pests 25:8–13, 1976) illustrated the morphology of the adult and immature stages of M. ussuriensis (Caradja, 1920), (Osada et al., Appl Entomol Zool 48:15–20, 2013) concluded that it is not M. ussuriensis but M. moriutii on the basis of adults of the type specimen and redescibed the adults of M. moriutii. Furthermore, (Osada et al., Appl Entomol Zool 50:297–309, 2015a) taxonomically revised the Japanese species of the genus and recognized a total of eight species, five species of which are known as a pest of shiitake mushroom. Therefore, it is necessary to know the identity of the immature stages described by (Moriuti, Forest Pests 25:8–13, 1976). In this study, the morphology of the larva and pupa of true M. moriutii is redescribed in detail. As a result, these morphological characteristics are in agreement with the illustrations by (Moriuti, Forest Pests 25:8–13, 1976). In addition, DNA barcodes sequence of M. aquilonis were examined, it is revealed that the seven Morophagoides species are clearly distinguished.

In this work, we advance the previously developed Through‐Space/Through‐Bond (TS/TB) orbital interaction analysis and extend it to a new Through‐Space/Through‐Bond Energy Decomposition Analysis (TS/TB‐EDA). These methods are applied to investigate the mechanism behind the transition mutation from guanine:cytosine (G:C) to adenine:thymine (A:T) in DNA containing O6‐methylguanine (O6‐MeG) lesions. The mutagenicity of O6‐MeG has long been debated, with various geometric and energetic factors proposed. Using TS/TB and TS/TB‐EDA, we compare the electronic structures of damaged and undamaged base pairs at the mutation site during DNA replication, emphasizing the energetic components that influence base pair binding. Our analysis explores the strengths of individual orbital interactions, such as ‐bonds and hydrogen bonds, as well as decomposes the total binding energy between DNA bases into the physical components. We find that the electronic structure of the O6‐MeG lesion closely resembles that of A rather than G, while the O6‐MeG:T pair exhibits energetic and geometric characteristics similar to A:T. This similarity suggests the explanation for the polymerase's preference for pairing O6‐MeG with T. The obtained results are consistent with experimental data and provide insights into the high O6‐MeG:T mismatch rate observed in O6‐MeG damaged DNA sequences.

ICON limb measurements of FUV dayglow emission are used to investigate thermospheric composition (O, N2 number density) and temperature responses to the January 2021 SSW event in the F region. NRLMSISE‐00 model and TIEGCM simulations are employed as the baselines to reveal the distinct features at middle‐low latitudes of Northern Hemisphere (0–40° $\mathit{{}^{\circ}}$N) at different altitudes (∼200–∼400 km). Although there were some magnitude differences using the two models as the baseline, SSW‐driven changes in all variables are almost consistent. O density decreased in the middle thermosphere but increased in the upper thermosphere in the afternoon sector in pressure coordinates. The transition levels of O perturbations changed with local time and latitude, mainly determined by the balance of two processes: the upwelling and adiabatic cooling. While O density had an enhancement in the morning sector in the whole F‐region height. N2 density increased, while the temperature decreased, both at almost all altitudes (pressure levels) in the F region. The magnitude of O and N2 enhancement as well as temperature decreases increased with the altitude. Additionally, the quantitative examination using NRLMSISE‐00 model as baseline found SSW‐driven O decreases of ∼3% and increases of ∼8%, N2 increases of ∼15%, and temperature decreases of ∼5%. While the quantitative estimation of N2 increases was relatively larger (∼20%) when using TIEGCM as baseline.

In recent years, significant research has focused on the fabrication of human phantoms and the evaluation of radiological imaging using advanced 3D printing technologies and diverse filament materials. This study investigates the absorbed dose due to the physical attenuation of polylactic acid phantoms within the diagnostic X-ray energy range, utilizing Monte Carlo simulations and a radiophotoluminescence glass dosimetry system. The phantoms were fabricated with infill percentages ranging from 20 to 100%, which were visually verified through radiographic imaging, and the reference dosimetry depths varied from 10 to 110 mm. Monte Carlo simulations were performed using the Geant4 Application for Tomographic Emission and the Particle and Heavy Ion Transport code System, demonstrating good agreement with experimental results. The average differences between simulations and measurements were 2.6, 2.7, and 3.1% at 80, 100, and 120 kVp, respectively, with uncertainties of approximately 1% under consistent experimental conditions. The energy dependence of absorbed dose as a function of depth was also examined. For the dosimetry system, the absorbed dose exhibited a more pronounced decrease at lower tube voltages and with reduced infill percentages, resulting in an average error of 6.2% compared to simulation results. These findings provide valuable insights into the development of fully filament-based, human-equivalent phantoms and their potential applications in radiation dosimetry using high-density filament materials for various radiation-related devices.

Objective To evaluate the effects of the number of neoadjuvant chemotherapy (NAC) cycles and the addition of adjuvant chemotherapy (AC) after NAC on overall survival (OS) of patients with muscle‐invasive bladder cancer (MIBC). Patients and Methods We retrospectively evaluated 1687 patients with cT2‐4NxM0 MIBC who received radical cystectomy (RC) alone or RC plus perioperative chemotherapy at 36 institutions within the Japanese Urological Oncology Group. We evaluated the effect of the number of NAC cycles (2 vs. ≥ 3 cycles) and the addition of AC on OS. Results Among the 1687 patients analyzed, 946 received a median of three NAC cycles. The pathologic complete response rate did not significantly differ between those who received 2 (22.9%) and ≥ 3 cycles (27.5%, p = 0.112). Moreover, no significant difference in OS was observed between the groups (p = 0.559). Multivariable Cox regression analysis showed that pathologic high‐risk (ypT2–4, pT3–4, or pN+) or cisplatin ineligibility were significantly associated with poor OS but not the number of NAC cycles (p = 0.238). We identified 942 pathologically high‐risk patients after RC who were eligible for AC. Notably, no significant OS improvement was observed with the addition of AC as intensive perioperative chemotherapy after NAC. The primary limitation was selection bias from confounding by clinical indication. Conclusions Our findings showed that three or more NAC cycles and the addition of AC may have limited effects on OS in MIBC patients who received RC.

Some maternally inherited endosymbionts are known to cause Cytoplasmic incompatibility (CI), in which uninfected females cannot or seldom produce offspring by mating with infected males. Mortality by CI may vary depending on the bacterial strain, the host’s genotype, or the host’s age. Mesenetia is an alphaproteobacterial endosymbiont infecting the coconut hispine beetle Brontispa longissima (Gestro) (Coleoptera: Chrysomelidae), a serious pest of the coconut palm. This bacterium was discovered in the Pacific clade B. longissima, which causes 100% CI mortality. The Mesenetia infection in the other Asian clade, which is considered more invasive than the Pacific clade, was then discovered; however, the CI was unknown. We investigated the CI ability of Mesenetia infecting the Asian clade using different ages of hosts originally collected in Japan. The effects of the host’s age on bacterial density were also investigated with qPCR. The results of crossing tests showed that infected males caused CI with approximately 70% mortality with uninfected females in all age groups: 21–30, 30–40, 60–70, or 90–100-day-old males. CI mortality did not differ among the males’ ages. Infected females rescued CI caused by infected males in all age groups: 15–20, 30–40, 60–70, or 90–100-day-old females. Results of qPCR showed that, in males, bacterial density did not diverge according to age in the testis, hindleg, foregut, midgut, and hindgut. In females, aged insects tended to have higher bacterial density than younger ones in the ovary and, to a lesser extent, in the hindgut.

Luminescent radicals are gathering much attention as a new class of luminescent material. We have synthesized a new carbazole oligomer (mono, di, tri, tetra) substituted luminescent tris (2,4,6-trichlorophenyl) methyl (TTM) radicals. The photoluminescence (PL) spectra showed emission stemmed from the excited state charge transfer character. Despite the increase in the highest occupied molecular orbital level of the carbazole oligomer associated with increasing the oligomer length, the PL maxima showed a blue shift from di- to tetra-oligomer substitution. This unexpected behavior was explained by quantum chemical calculations, including electron–electron repulsion. The electron–electron repulsion on the donor orbital decreases when the oligomer length increases and leads to the blue shift of the emission. The blue shift of the emission accompanied by an increase in the photoluminescence quantum yield by substituting a large π-conjugated donor to a TTM radical would be a unique method to control the photophysical property of the luminescent radical.

This study demonstrates a unique method for fabricating microscale gold bicrystals by combining epitaxial growth and bonding techniques. Single crystal NaCl substrates with different orientations were bonded using AgCl, followed by deposition of gold films via high-temperature radio-frequency sputtering with high deposition rate under low vacuum. Wet-polished NaCl substrates allowed the formation of high-quality gold bicrystals by combining the orientations {100} Au ||{100} NaCl , {110} Au ||{110} NaCl , and {111} Au ||{111} NaCl . Electron microscopy confirmed the crystal structure and the isolated GBs. Electromigration tests used grain boundary (GB) diffusion to fabricate microscale break junctions in bicrystal gold films, demonstrating uniform break junctions along isolated GBs. This is in contrast to irregular break junctions in polycrystalline films. The results suggest that specific deposition conditions—high rate, low vacuum, and moisture exposure— are key to achieving high quality bicrystals, offering potential for precise break junction device applications.

Compression tests of self-fluxing pellets were conducted at 300 K and high temperatures with prismatic test samples cut from the centre of pellets. Two types of pellets were used: one reduced with CO, and one reduced with H2. Prismatic-shaped specimens were fractured in a brittle manner during the compression tests at 300 K and 973 K. The fracture stress at 300 K of the specimen reduced with CO is nearly the same as that reduced with H2 while the fracture stress at 973 K of the specimen reduced with CO is higher than that with H2. They show plastic deformation at higher than 1173 K. The yield stress of both types of specimens is nearly the same at above 1173 K. Poisson's ratio varied during deformation, suggesting deformation mechanism changes as deformation proceeded. The strain distribution of a specimen deformed at 1273 K measured using digital image correlation showed plastic deformation accumulated near the pores. It is considered that not only the collapse of the pores but also the plastic deformability of the matrix itself influences the temperature dependence of the yield stress of pellets.

The in vivo circadian clock in single cyanobacteria is studied here by time-lapse fluorescence microscopy when the temperature is lowered below 25°C. We first disentangle the circadian clock behavior from the bacterial cold shock response by identifying a sequence of “death steps” based on cellular indicators. By analyzing only “alive” traces, we show that the dynamic response of individual oscillatory traces to a step-down temperature signal is described by a simple Stuart-Landau oscillator model. The same dynamical analysis applied to in vitro data (KaiC phosphorylation level following a temperature step-down) allows for extracting and comparing both clock’s responses to a temperature step down. It appears, therefore, that both oscillators go through a similar supercritical Hopf bifurcation. Finally, to quantitatively describe the temperature dependence of the resulting in vivo and in vitro Stuart-Landau parameters $\mu\left(T\right)$ and ${\omega}_{c}\left(T\right)$, we propose two simplified analytical models: temperature-dependent positive feedback or time-delayed negative feedback that is temperature compensated. Our results provide strong constraints for future models by revealing a specific time scale for transitory regimes in the cyanobacterial circadian system and its temperature dependence.

Prediction of severe disease (SVD) in patients with coronavirus disease (COVID-19) pneumonia at an early stage could allow for more appropriate triage and improve patient prognosis. Moreover, the visualization of the topological properties of COVID-19 pneumonia could help clinical physicians describe the reasons for their decisions. We aimed to construct predictive models of SVD in patients with COVID-19 pneumonia at an early stage on computed tomography (CT) images using SVD-specific features that can be visualized on accumulated Betti number (BN) maps. BN maps (b0 and b1 maps) were generated by calculating the BNs within a shifting kernel in a manner similar to a convolution. Accumulated BN maps were constructed by summing BN maps (b0 and b1 maps) derived from a range of multiple-threshold values. Topological features were computed as intrinsic topological properties of COVID-19 pneumonia from the accumulated BN maps. Predictive models of SVD were constructed with two feature selection methods and three machine learning models using nested fivefold cross-validation. The proposed model achieved an area under the receiver-operating characteristic curve of 0.854 and a sensitivity of 0.908 in a test fold. These results suggested that topological image features could characterize COVID-19 pneumonia at an early stage as SVD.

The Reynolds number dependence of the normalised energy dissipation rate $C_{\epsilon }=\epsilon L/u^3$ is studied, where $\epsilon$ is the energy dissipation rate, L is the integral length scale and u is the root-mean-square velocity. We present the derivation of the exact relationship between the normalised energy dissipation rate and integrated form of the Kármán–Howarth equation in homogeneous isotropic turbulence. The present mathematical formulation is valid for both forced and decaying turbulence. The discussion of $C_{\epsilon }$ is developed under the assumption that the term resulting from the nonlinear energy transfer appearing in $C_{\epsilon }$ is constant at sufficiently high-Reynolds-number turbulence. The fact that the integrated term originating from nonlinear energy transfer is constant plays the role of a lower bound in $C_{\epsilon }$ , implying that the energy dissipation rate is finite in high-Reynolds-number turbulence. Furthermore, the origin of the non-equilibrium dissipation law could be the imbalance between u and ${\rm d}L/{\rm d}t$ , the influence of external forces, or both. In decaying turbulence with forced turbulence as the initial condition, the imbalance between u and ${\rm d}L/{\rm d}t$ causes the non-equilibrium dissipation law. The validity of the theoretical analysis is investigated using direct numerical simulations of the forced and decaying turbulence.

Efficient and environmentally friendly recovery of platinum group metals from secondary resources can facilitate a sustainable society. This study explores a two-step process for extracting Pt from catalyst materials: chlorination using ferric chloride (FeCl3) vapor followed by leaching using hydrochloric acid. When the catalyst sample prepared by mixing Pt black and alumina powder was leached with 1 M HCl(aq.) at 313 K (40 °C) for 10 min, Pt was hardly dissolved in the solution. By contrast, after exposure to FeCl3 vapor at 573 ± 20 K (300 ± 20 °C) for 35 min, 92% of the Pt was extracted under the same leaching conditions. Furthermore, when a commercial Pt catalyst powder was subjected to chlorination, virtually all the Pt was extracted during subsequent leaching. The reaction products of Pt and FeCl3 vapor were examined through compositional analysis using scanning electron microscopy and energy-dispersive X-ray spectroscopy, and their crystalline structures were analyzed using X-ray diffraction. The products were identified as FePtCl6 and FeCl2. By reacting with FeCl3 vapor, Pt was converted into a complex chloride that is easily soluble in low-toxicity acids. Therefore, the proposed process can potentially improve the efficiency and environmental friendliness of Pt recovery from spent catalysts.

Python serves as a versatile programming language due to its diverse audience. This versatility, however, has a double-edged nature as it implies a multitude of learning examples, which can quickly become overwhelming for students. To explore these examples in an educational context, we investigate their usage in Python textbooks. Our approach involves the manual curation of 1,017 chapter titles from 76 Python textbooks. The results indicate that coding examples are prevalent, making up approximately 39.5% of the content compared to other topics. We then classified the example content into four types: Application Programming Interfaces, Data and Processing, Graphical User Interfaces, and others. We also identified a list of 19 Python libraries used in these various examples. To help educators and students, we showcase PyEdu, a Python Educational Example Visualizer that uses the results of the empirical study.

Synbiotic interventions have gained increasing attention for modulating gut microbiota and metabolic functions in obesity-related disorders. This study evaluated the effects of Limosilactobacillus reuteri KUB-AC5 (10⁸ CFU) and Wolffia globosa powder (6 g/day) using an in vitro continuous human gastrointestinal model. Fecal samples from obese donors were used to simulate the ascending and descending colon, with microbial viability, diversity, and metabolite production assessed over 14 days via culture-dependent and culture-independent methods. Synbiotic supplementation increased anaerobic bacterial counts by 2.6 log CFU/mL in the ascending colon and 2.2 log CFU/mL in the descending colon, with notable increases in lactic acid bacteria and reductions in Enterobacteriaceae. Metagenomic analysis revealed an increasing trend in microbial diversity and evenness after 7 days of treatment, though the changes were not statistically significant. PERMANOVA analysis confirmed significant shift in microbial community composition between stabilization, treatment, and washout periods (p < 0.05). Additionally, butyrate levels significantly increased (p < 0.05), while p-cresol, a deleterious metabolite, significantly decreased (p < 0.05). Bile acid composition was modulated, with increased tertiary bile acid 3-oxo-LCA and enhanced bile acid deconjugation, suggesting improved lipid metabolism and potential weight management benefits. These findings highlight the potential of synbiotic supplementation to enhance beneficial bacterial populations, improve microbial diversity, and support metabolic health in obesity management.