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SUMMARY For the study of the random velocity fluctuation of the solid Earth medium, it is useful to measure the collapse of a seismic wavelet with increasing travel distance and the excitation of coda waves. Radiative transfer theory (RTT) is a powerful tool for synthesizing the propagation of a seismic wavelet in random media statistically characterized by the power spectral density function (PSDF) of the fractional velocity fluctuation. The Born scattering coefficient is a key building block of RTT. As the centre wavenumber of a wavelet increases, the phase shift across the correlation length increases and the Born approximation leads to an extremely large forward scattering exceeding the applicable range of the perturbation method. In such a case, the Eikonal approximation is able to explain the envelope broadening with increasing travel distance; however, it can not explain the coda excitation. To overcome the difficulty, we have proposed a hybrid Monte Carlo (MC) simulation for scalar waves. In the case of von Kármán-type random media, when the centre wavenumber is higher than the corner wavenumber, taking the centre wavenumber as a reference, we divide the PSDF into two spectral components. Applying the Born and Eikonal approximations to the high- and low-wavenumber spectral components, we statistically evaluate the wide-angle scattering and the narrow-angle ray bending, respectively. The proposed MC simulation serially using two kinds of scattering processes successfully synthesizes the time trace of the wave energy density from the onset to the late coda. The travel-distance fluctuation derived from the one-way propagation of the Eikonal approximation is also important. This paper extends this method for the propagation of a vector wavelet in random elastic media. We suppose that random fractional fluctuations of the P- and S-wave velocities and the mass density are linearly proportional to each other, which maintains the linear polarization of an Swave throughout the scattering process. Using the hybrid MC simulation with the spectrum division, we synthesize three-component energy density time traces for the anisotropic radiation from a moment tensor source, from which we derive three-component root mean square (RMS) velocity amplitude time traces at different azimuths. In parallel, we synthesize the propagation of a vector wavelet in many realized random elastic media by the finite-difference simulation, then we calculate three-component RMS velocity amplitude time traces. Using them as a benchmark, we confirm the validity of the proposed MC simulation for specific cases.

研究ノート

“Katsura is shibui”—this persistent slogan originated in two special issues of House Beautiful published in 1960. Themed “Discover shibui” and “How to be shibui with American things,” these publications linked the image of the Katsura Detached Palace with shibui and employed this “untranslatable” word to evoke the notion of richness in simplicity. But as this article shows, Katsura’s global fame can be traced at least back to the early 1920s, when German scholars investigated the imperial villa as an example of Japanese timber construction, followed soon after by Japanese architects and critics. Shibui, in contrast, first became an aesthetic term when the Japanese government promoted it in the 1930s as part of a campaign to encourage foreign tourism. This study reconstructs the process through which a growing number of publications and international exchanges addressed these topics, culminating in the postwar period, when the initial contact between the two genealogies of Katsura and shibui sparked a heated aesthetic debate.

Iwate University has been operating a portfolio system termed “In Folio” since 2016, which has been serving as the driving force behind the institution's internal quality assurance system of education. It is designed to collect various types of information needed for internal quality assurance, accumulate records pertaining to student learning, and present the status of achievement to students. While establishing this system, discussions were held at the educational program level, including clarifying the relationship between the degree awarding policy and each of the subjects that make up the curriculum. However, discussions regarding improvement are ongoing based on the data. Based on this Iwate University initiative and previous studies, this paper proposes two points of view on building an internal quality assurance system for education: the first is to treat the system as a series of activities for improving university education, including, for example, FD, while the other is to collect and share data as much as possible. We suggest that this will advance discussions on substantive educational improvement strategies.

Colonic metastasis from ovarian cancer is extremely rare, with only seven reported cases. A 77-year-old woman who had previously undergone surgery for ovarian cancer was admitted to a local hospital with anal bleeding. Histopathological analysis confirmed the presence of adenocarcinoma. Colonoscopy revealed a descending colon tumor. The patient was diagnosed with Union for International Cancer Control T3N0M0 descending colon cancer or colon metastasis of the ovarian cancer. Laparoscopic left colectomy was performed; intraoperative frozen section diagnosis confirmed metastasis from ovarian cancer, and the absence of invasion to the serosal surface suggested hematogenous metastasis. This is the first case of colonic metastasis from ovarian cancer that was diagnosed using an intraoperative frozen section and laparoscopically treated.

Glycemic disorders involving large glucose fluctuations and recurrent hypoglycemia may lead to adverse cardiovascular events, including acute coronary syndrome (ACS). Flash glucose monitoring (FGM) has reportedly been useful for detecting latent glycemic disorders. However, only a few studies have so far reported latent glycemic disorders in coronary artery disease. Thus, we herein present a unique case of ACS due to intraplaque hemorrhage in a post-gastrectomy patient who had no apparent coronary risk, except for a latent severe glycemic disorder detected via FGM. This masked etiology should be considered in ACS patients who have no apparent cardiovascular risks in order to improve their cardiovascular outcomes.

Acquired fibroblast growth factor (FGF) 23-related hypophosphatemic osteomalacia is characterized clinically by muscle weakness, bone pain, and fractures. Its biochemical features include hypophosphatemia, caused by renal phosphate wasting, and inappropriately normal or low 1,25-dihydroxy-vitamin D levels. Recently, burosumab, a fully human monoclonal antibody targeting FGF23, was approved for the treatment of FGF23-related hypophosphatemic rickets and osteomalacia. We report the case of a 75-year-old Japanese woman with decompensated liver cirrhosis and hepatic encephalopathy, caused by primary biliary cholangitis, who complained of back pain and limited mobility resulting from multiple vertebral fractures. She was not receiving iron infusion therapy and denied alcohol consumption. The patient exhibited hypophosphatemia with a low tubular maximum reabsorption of phosphate per unit glomerular filtration rate (TmP/GFR) and a high circulating concentration of FGF23. Conventional therapy with alfacalcidol and oral phosphate slightly improved her serum phosphate concentration and back pain, but she experienced a hip fracture, causing her to become wheelchair-dependent. Burosumab was initiated 8 weeks after the hip fracture, which increased her serum phosphate concentration and TmP/GFR. Her mobility gradually improved, such that she could walk without a cane after 16 weeks of treatment. Her lumbar bone mineral density increased after 48 weeks. Hepatic encephalopathy developed once before the initiation of treatment and twice after the initiation of the therapy, but her liver function was preserved. This is the first study to report the efficacy and safety of burosumab treatment for FGF23-related hypophosphatemic osteomalacia with decompensated liver cirrhosis.

Advances in medicine have resulted in increased longevity, which has consequently led to unexpected geriatric syndromes, such as frailty and sarcopenia. Patients with end-stage kidney disease, especially those receiving dialysis treatment, often show characteristic reductions in body protein and energy storage, termed protein energy wasting (PEW). Therefore, maintenance of nutritional condition has a key role in defending against both geriatric syndromes and PEW, which share several components in elderly individuals undergoing hemodialysis. To counteract the development of an undesirable condition, nutritional evaluation is indispensable. In addition to simple measurements of body mass index, and serum albumin and creatinine, a composite nutritional assessment including a malnutrition inflammation score is useful, although subjective elements are included and a well-trained examiner is required. On the other hand, the geriatric nutritional risk index and nutritional risk index for Japanese hemodialysis patients (NRI-JH) are objective tools, and easy to use in clinical settings. Undernutrition is closely related to infectious events and the results of an infection are often serious in elderly patients, even those with survival, with large medical costs incurred. Together with appropriate nutritional evaluation, it is necessary to clarify the underlying relationship of PEW with infection for improvement of prognosis in affected elderly individuals.