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The southern Kuril Trench is one of the most seismically active regions in the world. In this study, marine surveys and observations were performed to construct fault models for possible outer-rise earthquakes. Seismic and seafloor bathymetric surveys indicated that the dip angle of the outer-rise fault was approximately 50°–80°, with a strike that was slightly oblique to the axis of the Kuril Trench. The maximum fault length was estimated to be ~ 260 km. Based on these findings, we proposed 17 fault models, with moment magnitudes ranging from 7.2 to 8.4. To numerically simulate tsunami, we solved two-dimensional dispersive wave and three-dimensional Euler equations using the outer-rise fault models. The results of both simulations yielded identical predictions for tsunami with short-wavelength components, resulting in significant dispersive deformations in the open ocean. We also found that tsunami generated by outer-rise earthquakes were affected by refraction and diffraction because of the source location beyond the trench axis. These findings can improve future predictions of tsunami hazards. [ABSTRACT FROM AUTHOR]

We present a novel method for coastal tsunami prediction utilizing a denoising autoencoder (DAE) model, one of the deep learning algorithms. Our study focuses on the Tohoku coast, Japan, where dense offshore bottom pressure gauges (OBPGs), called S-net, are installed. To train the model, we generated 800 hypothetical tsunami scenarios by employing stochastic earthquake models (M7.0–8.8). We used synthetic tsunami waveforms at 44 OBPGs as input and the waveforms at four coastal tide gauges as output. Subsequently, we evaluated the model's performance using 200 additional hypothetical and two real tsunami events: the 2016 Fukushima earthquake and 2022 Tonga volcanic tsunamis. Our DAE model demonstrated high accuracy in predicting coastal tsunami waveforms for hypothetical events, achieving an impressive quality index of approximately 90%. Furthermore, it accurately forecasted the maximum amplitude of the 2016 Fukushima tsunami, achieving a quality index of 91.4% at 15 min after the earthquake. However, the prediction of coastal waveforms for the 2022 Tonga volcanic tsunami was not satisfactory. We also assessed the impact of the forecast time window and found that it had limited effects on forecast accuracy. This suggests that our method is suitable for providing rapid forecasts soon after an earthquake occurs. Our research is the first application of an artificial neural network to tsunami prediction using real observations. In the future, we will use more tsunami scenarios for model training to enhance its robustness for different types of tsunamis. [ABSTRACT FROM AUTHOR]

We examined whether it is possible to estimate the tsunami source model of the 2011 Tohoku-Oki earthquake from a comparison of numerical simulations of tsunami propagation and sediment transport, the measured trace heights, and the sediment thickness of tsunami deposits. Twelve models with different subfault numbers were prepared based on a reference model inferred from tsunami waveform inversion. The reference model with 55 subfaults considering rupture propagation and the model with instantaneous slip successfully reproduced both the tsunami trace heights and sediment thickness distribution of tsunami deposits in the Idagawa Lowland and Sendai Plain. Other models with the same moment magnitude but fewer subfaults could not reproduce the observed trace heights, and the reproducibility of sediment thickness distribution strongly depended on the slip distribution. Models with increased slip amounts and moment magnitude could reproduce the trace heights; however, the simulated sediment thickness was underestimated for the Idagawa Lowland while overestimated for the Sendai Plain. Our results indicate that the combination of trace heights, sediment thickness of tsunami deposits, and numerical simulations of tsunami propagation and sediment transport can be used to estimate historical earthquakes and tsunamis. Efforts should be made to increase the number of subfaults for the study of historical events, although the obtained solutions may not be unique because of fewer trace heights or tsunami deposit data. [ABSTRACT FROM AUTHOR]

The island of Sulawesi, Indonesia, is located in a complex and tectonically active region, and has experienced tsunamis in the past. One of the major earthquake and tsunami events was the 23 February 1969 event that struck the Majene region in western Sulawesi Island. Interpretation of the historical accounts revealed that the Mw 7.0 earthquake generated strong intensity up to VIII on the Modified Mercalli Intensity scale. The earthquake was followed by an unusually high tsunami of 4 m that rapidly decayed within 25 km from the highest observation site. Hypocentre and earthquake mechanism analyses confirmed that it was an inland earthquake with a thrust mechanism. Ground motion modelling is able to reproduce the earthquake intensity but earthquake scenarios are unable to reconstruct the tsunami observations. A plausible solution to explain the tsunami report is from a combined scenario of an earthquake and a submarine mass failure of 0.5 km 3 . [ABSTRACT FROM AUTHOR]

We estimated the time difference between the 1854 CE Ansei–Tokai and Ansei–Nankai earthquakes from tidal records of two tide gauge stations (San Francisco and San Diego) on the west coast of North America. The first signals of the Ansei–Tokai tsunami were apparent, whereas those of the Ansei–Nankai tsunami were obscured by the later waves of the Ansei–Tokai tsunami. Waveforms of the Ansei–Nankai tsunami simulated with nonlinear dispersive wave theory by assuming an origin time of 07:00 GMT on 24 December arrived earlier than in the observations. The normalized root mean square and the misfit between the simulated and observed waveforms of the Ansei–Nankai tsunami showed a time difference between them of approximately 0.4 h. This finding suggests that the actual origin time of the Ansei–Nankai tsunami was approximately 07:24 GMT on 24 December. A previous study estimated the origin time of the Ansei–Tokai tsunami to be about 00:30 GMT on 23 December. Thus, we concluded that the time difference between the 1854 CE Ansei–Tokai and Ansei–Nankai tsunamis was 30.9 h. Despite the significant difference in the time resolution between the seasonal timekeeping system used in Japan in 1854 and waveform digitization, our result is roughly in agreement with historical descriptions of the tsunamis, suggesting that such information can be effectively used to determine the origin times of historical earthquakes. [ABSTRACT FROM AUTHOR]

Although tsunamis are dispersive water waves, hazard maps for earthquake-generated tsunamis neglect dispersive effects because the spatial dimensions of tsunamis are much greater than the water depth, and dispersive effects are generally small. Furthermore, calculations that include non-dispersive effects tend to predict higher tsunamis than ones that include dispersive effects. Although non-dispersive models may overestimate the tsunami height, this conservative approach is acceptable in disaster management, where the goal is to save lives and protect property. However, we demonstrate that offshore frequency dispersion amplifies tsunamis caused by outer-rise earthquakes, which displace the ocean bottom downward in a narrow area, generating a dispersive short-wavelength and pulling-dominant (water withdrawn) tsunami. We compared observational evidence and calculations of tsunami for a 1933 Mw 8.3 outer-rise earthquake along the Japan Trench. Dispersive (Boussinesq) calculations predicted significant frequency dispersion in the 1933 tsunami. The dispersive tsunami deformation offshore produced tsunami inundation heights that were about 10% larger than those predicted by non-dispersive (long-wave) calculations. The dispersive tsunami calculations simulated the observed tsunami inundation heights better than did the non-dispersive tsunami calculations. Contrary to conventional practice, we conclude that dispersive calculations are essential when preparing deterministic hazard maps for outer-rise tsunamis. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the feasibility of a combination therapy of photodynamic therapy (PDT) and airway stent placement using a transparent silicone stent (gold studded stent [GSS]). Laser irradiation (664 nm, continuous wave) was performed through the GSS using a straight and cylindrical fiber 1.0 cm away from a power meter. There are two types of GSS: the TD type for the trachea and the BD type for the bronchus. Laser outputs were set to 150 mW, 180 mW, 210 mW, 240 mW, 270 mW, and 300 mW. The laser powers passing through the both types of GSS were measured three times for each outputs and the averages were calculated. Based on the results, animal experiment was performed using two female pigs. Under general anesthesia, a GSS (BD type) was inserted into trachea of pigs, and PDT using NPe6 as a photosensitizer was performed by 100 J/cm2 laser irradiation on parts of the trachea with and without a GSS. Immediately after and 1 week after PDT, pig tracheas were harvested and histological analysis was performed. Histological analysis of areas with or without the stent showed edematous changes between the cartilage and submucosal layer immediately after PDT, and necrotic changes 1 week later. The effectiveness of NPe6-PDT for pigs' trachea covered by the stent was same as trachea without the stent. The use of a GSS may enable PDT to be effective even in the area covered by the stent. [ABSTRACT FROM AUTHOR]

Background: The open-label, randomized, active-controlled KEYNOTE-045 study (NCT02256436) showed that second-line pembrolizumab significantly improved overall survival (OS) of patients with advanced/metastatic urothelial cancer (UC) that progressed after first-line platinum-containing chemotherapy, compared with standard chemotherapy (paclitaxel, docetaxel, or vinflunine). Pembrolizumab is approved for patients with bladder cancer in Japan. Patients and methods: Analysis was performed in the subgroup of Japanese patients enrolled in the KEYNOTE-045 study. Coprimary end points were OS and progression-free survival (PFS). Objective response rate (ORR) and safety were secondary end points. Results: Fifty-two Japanese patients (pembrolizumab, n = 30; chemotherapy, n = 22) were followed up for a median of 26.1 months. Patients who received pembrolizumab compared with chemotherapy had a 19% lower risk for death (hazard ratio [HR] 0.81, 95% CI 0.44–1.50); after adjusting for baseline covariates, the HR for OS was 0.61 (95% CI 0.32–1.15). The 24-month OS rate was higher with pembrolizumab (26.9% vs 14.3%). PFS was 2.0 and 4.9 months for pembrolizumab and chemotherapy, respectively (HR 1.71, 95% CI 0.95–3.08). ORR was similar for pembrolizumab and chemotherapy (20.0% vs 18.2%); durability of response was higher with pembrolizumab: 67% and 33% of patients, respectively, maintained a response for > 12 months. Treatment-related adverse events, including grade 3–5 events, occurred less frequently with pembrolizumab. Conclusions: Pembrolizumab provided durable antitumor activity in patients with locally advanced/metastatic UC that progressed after platinum-containing chemotherapy in the overall population and in the Japanese subgroup; safety profile was consistent with that previously observed for pembrolizumab. [ABSTRACT FROM AUTHOR]

We report a case of metachronous multiple lung adenocarcinoma at the cut-end, diagnosed 4 years after sublobar resection for adenocarcinoma in situ (AIS), on the basis of discordance of epidermal growth factor receptor ( EGFR) mutation status between the first and second tumor. The patient was an 81-year-old Japanese man, whose chest computer tomography (CT) scan showed mixed ground-glass opacity in the right upper lobe of the lung. Wedge resection was performed and a diagnosis of AIS, non-mucinous (18 × 14 mm), with a margin of 6 mm, was made. A tumor at the cut-end was seen on a CT scan 4 years later, and abnormal uptake was identified by fluorine-18 fluorodeoxyglucose-positron emission tomography. Right upper lobectomy and lymph node dissection were performed and the tumor was diagnosed as invasive adenocarcinoma, acinar predominant. Discordance of EGFR mutation status between the first tumor, harboring exon 19 deletion, and the second tumor, having an L858R point mutation in exon 21, revealed that the second tumor was metachronous multiple lung cancer. This case demonstrates the necessity of comparing EGFR mutation status between the first tumor and the second tumor at the cut-end. [ABSTRACT FROM AUTHOR]

A large amount of buildings was damaged or destroyed by the 2011 Great East Japan tsunami. Numerous field surveys were conducted in order to collect the tsunami inundation extents and building damage data in the affected areas. Therefore, this event provides us with one of the most complete data set among tsunami events in history. In this study, fragility functions are derived using data provided by the Ministry of Land, Infrastructure and Transportation of Japan, with more than 250,000 structures surveyed. The set of data has details on damage level, structural material, number of stories per building and location (town). This information is crucial to the understanding of the causes of building damage, as differences in structural characteristics and building location can be taken into account in the damage probability analysis. Using least squares regression, different sets of fragility curves are derived to demonstrate the influence of structural material, number of stories and coastal topography on building damage levels. The results show a better resistant performance of reinforced concrete and steel buildings over wood or masonry buildings. Also, buildings taller than two stories were confirmed to be much stronger than the buildings of one or two stories. The damage characteristic due to the coastal topography based on limited number of data in town locations is also shortly discussed here. At the same tsunami inundation depth, buildings along the Sanriku ria coast were much greater damaged than buildings from the plain coast in Sendai. The difference in damage states can be explained by the faster flow velocities in the ria coast at the same inundation depth. These findings are key to support better future building damage assessments, land use management and disaster planning. [ABSTRACT FROM AUTHOR]

A 47-year-old man with optimally controlled type-2 diabetes mellitus and chronic hepatitis B was admitted to a local hospital because of a 1-week history of cough and high-grade fever. He was diagnosed with Pneumocystis pneumonia (PCP) and Klebsiella pneumonia from a chest radiograph and sputum. Simultaneously, he was found to have HIV infection with a CD4 count of 76/μl. Despite alteration of treatment secondary to the development of allergic reaction to trimethoprim-sulfamethoxazole (TMP-SMX), the patient was able to complete a 3-week therapy for PCP after being switched to pentamidine isetionate. After the treatment of PCP, he was referred to our hospital for the initiation of anti-HIV therapy. He presented with recurrent high-grade fever of a few days' duration prior to his initial visit, which subsequently led to his admission. Chest computed tomography (CT) showed the enlargement of a previously identified infiltrate in the left upper lung field, and the sputum culture upon admission was positive for Gram-positive branching rods; the organism was later identified as Nocardia exalbida. Due to his allergy to sulfonamide, the patient was treated with imipenem (IMP) and amikacin (AMK) given intravenously for 17 days, followed by garenoxacin (GRNX) taken orally for 6 months, without any adverse effects. The chest infiltrate resolved completely, and he remains stable without relapse 8 months after the completion of the therapy. Pulmonary nocardiosis should be considered as a differential diagnosis of recurring pneumonia in immunocompromised patients, especially in HIV-infected individuals. Oral administration of GRNX following IMP and AMK can be used as an alternative to TMP-SMX therapy in cases of pulmonary nocardiosis caused by N. exalbida. [ABSTRACT FROM AUTHOR]