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An effective evaluation method for understanding fermentation is required to support the implementation of newly developed yeast strains in brewing. Our group developed a multi-functional separation mode-ion chromatography (MFS-IC) with conductivity and refractive index detectors to separate key species (glucose, ethanol, and organic acids: pyruvate, citrate, L-malate, and succinate) with ethyl α-D-glucoside and glycerol to understand the fermentation behavior in brewing. Optimal chromatographic resolutions for determining eight different key species in rice wine by the MFS-IC were obtained in 45 min on low-molecular size-exclusion chromatographic separation columns modified with a strong cation-exchanger as the stationary phase with an eluent of L-pyroglutamic acid. Understanding the behavior of analytes in rice wine samples during rice wine fermentation enables the monitoring of the progress of saccharification, glycolysis, ethanol fermentation, and the tricarboxylic acid (TCA) cycle. These results are expected to contribute to understanding fermentation characteristics and implementing newly developed yeast strains in the fermentation field.

In this study, ion-exclusion/cation-exchange chromatography (IEC/CEC) using dual-ion-exchange groups (carboxy and sulfo groups) for the simultaneous determination of anions (SO42−, Cl−, NO3−, and HPO42−) and cations (Na+, NH4+, K+, Mg2+, and Ca2+) was developed. By using the combination of dual-ion-exchange groups, simultaneous separation of inorganic ions with HPO42− was achieved that was impossible by the conventional IEC/CEC based on the single-ion-exchange group (carboxy group). This method was applied to the monitoring of inorganic ionic nutrients in fertilizer solution samples in hydroponic culture. As a result, a higher peak resolution of inorganic anions and cations with phosphate ion using IEC/CEC with dual-ion-exchange groups was achieved in the absence of matrix effects. In addition, the developed method helps to understand the behavior of ionic nutrients in fertilizer solution during hydroponic cultivation and is potentially useful for the individual fertilization of ionic nutrients.

Introduction: While the Tokyo Guidelines 2018 suggest primary stone removal for mild to moderate cholangitis, a guideline for severe acute cholangitis is not mentioned. We, therefore, investigated the clinical outcomes of patients with severe acute cholangitis to confirm the usefulness and safety of primary stone removal. Method: This study included 104 severe acute cholangitis patients without gallstone pancreatitis diagnosed at our institution between January 2014 and December 2020. Patients with percutaneous transhepatic biliary drainage as the primary drainage, bile duct stenosis, and endoscopically unidentified bile duct stones were excluded from this study. The clinical results of 14 patients with primary stone removal (primary group) and 23 patients with elective stone removal (elective group) were then retrospectively examined (excluding abnormal values due to underlying diseases). Results: Upon comparing the patient characteristics between groups, the elective group had significantly higher cardiovascular dysfunction (57% vs 7%; p = 0.004), septic shock (39% vs 0%; p = 0.006), disseminated intravascular coagulation treatment (57% vs 14%; p = 0.016), and positive blood cultures (91% vs 43%; p = 0.006) than those in the primary group. Endoscopic sphincterotomy for naïve papilla (90% vs 21%; p = 0.01) and endoscopic nasobiliary drainage (50% vs 9%; p = 0.014) were higher in the primary group, while endoscopic biliary stenting (7% vs 87%; p Discussion: There were no significant differences in adverse events or complete stone removal rates between the two groups. In the primary group, the period from the first endoscopic retrograde cholangiopancreatography to stone removal (0 days vs 12 days; p Conclusion: If patients are appropriately selected, bile duct stones may be safely removed for the treatment of severe acute cholangitis.

Mt. Fuji, the tallest volcano in Japan, has not erupted since the Plinian eruption in 1707, but its volcanic activity has not finished. Here, using GNSS (Global Navigation Satellite System) time-series data, we investigate an inflation event of Mt. Fuji in 2008–2010. Referring to recent studies of igneous processes, we focus on “vertically-extensive” magma systems and estimate depth distribution of geodetic inflation sources. A sparsity-promoting L1 regularization algorithm for inversion analysis allows us to improve performance of data fitting. Our result shows that the inflation sources were mainly distributed in a depth range from 20 km to 15 km, and the total volume change was on the order of 0.01 cubic kilometers (approximately a sphere of radius 100 m). The 15 km depth may correspond to the upper boundary of partial melt of basaltic magma. Our sparsity-promoting method is useful to constrain magma movement from limited observation data.

Slow deformations associated with a subducting slab can affect quasi-static displacements and seismicity over a wide range of depths. Here, we analyse the seismotectonic activities at the Tonga-Trench subduction zone, which is the world’s most active area with regard to deep earthquakes, using data from GNSS and an earthquake catalogue. We find that trenchward transient displacements and quiescence of deep earthquakes, in terms of background seismicity, were bounded in time by large intraslab earthquakes in 2009 and 2013. We call this event as "slow deformation event”. It may have been triggered by a distant and shallow M8.1 earthquake, which implies a slow slip event at the plate interface or a temporal acceleration of the subduction of the Pacific Plate.

We infer the postseismic deformation mechanisms following the 2011 Tohoku megathrust earthquake via an analysis of onshore geodetic observations. We focus on the temporal decay characteristics of postseismic deformation using continuous time-series data at time scales that span many orders of magnitude by means of high-rate GNSS data. Our analysis indicates Omori-like power-law decay of the horizontal ground displacement rates, with p-value (0.69) that is significantly smaller than that of the aftershock occurrence (~ 1). This slow decay implies a (non-Maxwellian) viscoelastic relaxation mechanism other than afterslip since immediately after the mainshock, which is inferred using only onshore geodetic data. Spatial distribution of the Omori parameters implies that the postseismic deformation will continue over 100 years in a down-dip area of the northern part of the mainshock fault. The decay characteristics of vertical displacement rates are also almost Omori-like, but data deviation from the fitting line several 100 days after the mainshock might reflect the change of the dominant mechanism of the postseismic deformation. This multi-time scale geodetic approach will provide important constraints for future viscoelastic models of Earth’s interior. Rapid mantle flow with power-law creep explains deformation after the 2011 Tohoku mega-quake.

Background/purpose This study investigated whether measuring pancreatic blood volume (PBV) on whole pancreatic perfusion computed tomography (P-CT) can predict the progression of walled-off necrosis (WON) in patients with acute pancreatitis (AP). Methods A single-center, retrospective cohort study was conducted between December 2015 and December 2016. The participants were divided into two groups: 14 patients with WON and 15 patients without WON. PBV was measured within 72 hours after the diagnosis of AP, and the final diagnosis of WON was made by contrast-enhanced CT (CE-CT) or endoscopic ultrasonography (EUS) 4 weeks after the onset of AP. Results The minimum CT value did not differ significantly between the two groups. On the other hand, the minimum PBV was significantly lower in the WON group than in the without WON group (1.4 (0.9-9.9) vs 19.8 (8.2-21.7) mL/100 mL, respectively; P = .02). The cutoff value of the minimum PBV for WON was 16.5 mL/100 mL (sensitivity 100%, specificity 67%, AUC 0.85; P = .001). Conclusions Whole pancreatic P-CT can evaluate pancreatic ischemia visually and quantitatively. The minimum PBV measurement on whole pancreatic P-CT within 72 hours after the diagnosis of AP contributes to the prediction of progression of WON.

Background and study aims This study investigated the feasibility of side-by-side (SBS) partially covered self-expandable metal stent (PCSEMS) placement for unresectable malignant hilar biliary obstruction (MHBO). Patients and methods We retrospectively analyzed 33 patients from a single center who underwent endoscopic biliary drainage for unresectable MHBO from July 2013 to June 2015. In all patients with bilateral obstruction during complete bilateral intrahepatic cholangiograms, we performed endoscopic SBS placement of a 6-mm diameter PCSEMS using an 8-French delivery system. All patients underwent endoscopic sphincterotomy. Generally, patients with recurrent biliary obstruction (RBO) after stent placement underwent endoscopic reintervention. Our study outcomes included the technical and functional success rates, RBO rate, time to RBO (TRBO), reintervention rate, and incidence of adverse events. Results Seventeen patients with unresectable MHBO during complete bilateral intrahepatic cholangiograms underwent endoscopic SBS PCSEMS placement (median age, 78 years; men, 9). Lesions were Bismuth types II (n = 10), III (n = 1), and IV (n = 6), including 10 cholangiocarcinomas, 3 gallbladder cancers, and 4 metastatic cancers. In all patients, the PCSEMS was placed across the duodenal papilla. The technical and functional success rates were 100 % and 82 %, respectively. The median procedure time was 43 minutes (interquartile range [IQR]: 36 – 52 minutes). Twelve patients had RBO (71 %), including 9 stent occlusions due to sludge and 3 stent migrations. The median TRBO was 79 days (IQR: 58 – 156 days) during the follow-up period (median 192 days [IQR: 88 – 551 days]). The median TRBO of patients with Bismuth type II lesions was significantly longer than that of patients with Bismuth types III and IV lesions (87 days [IQR: 70 – 244 days] vs. 54 days [IQR: 35 – 100 days]; P = 0.030). Thirteen patients (76 %) required endoscopic reintervention. Endoscopic stent removal was possible in 6 patients without tumor ingrowth into the uncovered distal part of the stent. One late adverse event (≥ 31 days) occurred (cholangitis). Conclusions Endoscopic SBS placement of a PCSEMS was feasible in patients with unresectable MHBO. Additionally, reinterventional stent removal was possible in the absence of tumor ingrowth.

Severe acute pancreatitis (SAP) is a risk factor for candidemia. We report a case of candida endophthalmitis in a 67-year-old man who was admitted to a hospital due to SAP with poorly controlled diabetes. After treatment for SAP, he was diagnosed with candidemia and candida endophthalmitis. We chose appropriate antifungal agents based on the results of a bacterial culture test. After treatment, the disappearance of Candida albicans (C. albicans) from the blood stream was confirmed in blood cultures. In addition, exudative plaques consistent with a fungal infection disappeared. After a diagnosis of candidemia is made, it is important to administer appropriate antifungal therapy and perform frequent ophthalmologic examinations.

Background: This study investigated the safety of endoscopic sphincterotomy in patients undergoing antithrombotic treatment. Methods: From January 2014 to December 2016, a single-center retrospective study was conducted. Of the 80 patients with naïve papilla receiving antithrombotic treatment who underwent endoscopic sphincterotomy, 76 patients were retrospectively analyzed. We divided the participants into two groups as follows: 45 patients who discontinued antithrombotic treatment (discontinuation group) and 31 patients who continued antithrombotic treatment (continuation group). We evaluated the safety of endoscopic sphincterotomy in patients with naïve papilla who received antithrombotic treatment. Results: The percentage of patients requiring emergency endoscopic retrograde cholangiopancreatography in the continuation group was significantly higher than that in the discontinuation group (55% vs 11%; p = 0.001). The incidence of adverse events did not differ significantly between the two groups. Neither bleeding nor perforation occurred in either group. The length of hospital stay did not differ significantly between the two groups. Conclusions: Endoscopic sphincterotomy in patients undergoing antithrombotic treatment may be safe if the guidelines for gastroenterological endoscopy in patients undergoing antithrombotic treatment are followed.

Correction In the publication of this article (Kitamura et al., 2017), there was an error in Fig. 11 which incorrectly indicated ‘Serpulidae sp. should instead read ‘Serpulidae.’ Italicized. It should not have indicated figures ‘Specimen of an emerged barnacle’, ‘Study area’ and their captions and the caption of the Fig. 11 itself was indicated twice. The error

We perform numerical experiments simulating grain shear events in a fault zone based on a three-dimensional Distinct Element Method. We investigate the effects of initial arrangement of grains and intergranular frictional coefficient for the inertial number I around 10-3. We find that a variety of event modes, such as Riedel shear, depends on the initial arrangement. We further clarify that microscopic slip velocity of intermittent events does not simply correlate with the frictional coefficient. [ABSTRACT FROM AUTHOR]

Interferometric Synthetic Aperture Radar (InSAR) can produce an image of detailed crustal deformation without any surface observation point. A SAR satellite, Sentinel-1, developed by the European Space Agency (ESA) has performed frequent observations of the same regions with C-band microwaves. In the present study, we investigate recent crustal deformations of two volcanic regions in Japan, i.e. Mt. Fuji and Izu-Oshima Island, using data acquired by Sentinel-1. First, a comparison of the InSAR time-series data (more than 20 times a year on average) with the Global Navigation Satellite System (GNSS) time-series data, at the coordinates of each GNSS station, confirmed close similarities between displacement rates (trends) of the InSAR and GNSS data around Mt. Fuji, although the InSAR data tend to include some apparent annual variation. Then, we applied a decomposition method to the InSAR data into two directions: East-West and Up-Down. For Mt. Fuji, the boundary where the direction of the displacement rates is changing, corresponds approximately to the strike of the dike in the subsurface. For Izu-Oshima Island, the data point out a faster deformation in the eastern part of the island, however, whether it is a true signal or not remains to be clarified. [ABSTRACT FROM AUTHOR]

We try to detect an unidentified signal from the surface motion at northeastern Japan immediately after the 2011 Tohoku earthquake. A focused frequency range is 10–100 mHz (10–100 s). We find a peaky signal with frequency of about 38 mHz (26 s) based on the horizontal-to-vertical (H/V) spectral ratio using the high-rate GNSS data at 382 GEONET stations. We are not able to identify locality of the signal. The signal appears several minutes after the passing of surface wave fronts. The duration of the signal is about 2 min. Since the origin of the 38 mHz signal is unlikely to be local hydrologic tremors, tectonic tremors, or the tsunami, we speculate that the 38 mHz signal originates from a kind of a characteristic oscillation of Northeastern Japan triggered by the 2011 Tohoku earthquake. A normal-mode simulation implies that high-order radial overtones could create the signal with a spherically-layered velocity structure, however, the detailed mechanism of the signal still remains a mystery.

To clarify the Holocene uplift history of the Izu Islands, Japan, we analyze the elevations and 14C ages of emerged sessile assemblages measured by accelerator mass spectrometry (AMS) on the islands of Niijima, Jinaijima, Shikinejima, and Kouzushima, on the northern Zenisu Ridge. The results suggest that uplift events took place after AD 1950 (uplift event 1), during AD 786–1891 (uplift event 2), during AD 600–1165 (uplift event 3), and during AD 161–686 (uplift event 4), although uplift events 3 and 4 are identified only at Kouzushima. The minimum amount of uplift was estimated to be 0.4–0.9 m in uplift event 1, 2.4–2.7 m in uplift event 2, 3.6 m in uplift event 3, and 3.3–8.1 m in uplift event 4. These events could have been caused by volcanic activity or strong earthquakes. There also remains the possibility that uplift event 2 was caused by the AD 1498 Meio earthquake; in contrast to the previous interpretation, the ages of uplift events are significantly older than the earthquake, based on conventional (non-AMS) methods.

Aim: To investigate outcomes of endoscopic bilateral side-by-side placement across the papilla using 10-mm-diameter uncovered self-expandable metal stents for unresectable malignant hilar biliary obstruction. Methods: We retrospectively analyzed 23 patients who underwent endoscopic biliary uncovered self-expandable metal stent placement for unresectable malignant hilar biliary obstruction between January 2015 and September 2016 at our institution. We performed endoscopic side-by-side placement across the papilla using 10-mm-diameter longer-model uncovered self-expandable metal stents. Outcomes included the technical and functional success rates, recurrent biliary obstruction rate, time to recurrent biliary obstruction, reintervention rate, and incidence of adverse events other than recurrent biliary obstruction. Results: Of the 23 patients, 10 with malignant hilar biliary obstruction underwent endoscopic side-by-side uncovered self-expandable metal stent placement across the papilla (median age, 83 years; 6 men). The locations of malignant hilar biliary obstruction were Bismuth types II ( n = 3), III ( n = 3), and IV ( n = 4). The median common bile duct diameter was 8 mm. The technical and functional success rates were 100% and 80%, respectively. Seven patients (70%) developed recurrent biliary obstruction because of stent occlusions, including early hemobilia in two patients and late tumor ingrowth in five patients. The median time to recurrent biliary obstruction was 66 (95% confidence interval: 29–483) days. Six patients (60%) required reintervention, and 1 (10%) underwent transcatheter arterial embolization for right hepatic arterial pseudoaneurysm. Early adverse events other than recurrent biliary obstruction occurred in four patients and late adverse event in one patient. Conclusion: Endoscopic side-by-side placement across the papilla using 10-mm-diameter uncovered self-expandable metal stents was technically feasible for unresectable malignant hilar biliary obstruction; however, it might be better to avoid this method for patients with malignant hilar biliary obstruction because of high recurrent biliary obstruction rate and shorter time to recurrent biliary obstruction.

S U M M A R Y We explore the use of on-land GPS observations to detect deformation due to tsunami propagation near source regions of large interplate earthquakes. Here, we focus on the Mw 9 Tohoku-oki earthquake, which occurred around 14:46 (JST) on 2011 March 11. We consider GPS data in the time span 14:54–15:22 (JST) along the Sanriku coast, where the tsunami had the largest amplitude. The displacement data shows the signatures of large aftershocks as well as post-seismic fault slip (afterslip). These effects are particularly evident in the east component. From the horizontal displacement vectors, we construct a simple fault model for the early phase of the afterslip. Mean slip velocity of the early afterslip reaches 0.1 mm s−1. By compiling the early afterslip velocity of recent interplate earthquakes around that region, we find its increasing trend with the main shock magnitude. This scaling relation may reflect higher stressing rates at edges of larger main shock faults. Separately, we forward calculate land deformation due to tsunami height changes based on a tsunami simulation. Tsunami-induced deformation is only evident in the vertical direction at coastal GPS stations. The predicted subsidence amounts at some coastal stations can account for a large portion of the residuals between the observation and the modelled deformation due to the fault slip.

[1] The 2011 Tohoku earthquake demonstrated that extremely large seismic slip can occur at shallow plate interfaces in subduction zones. The large slip area for the Tohoku earthquake included the source region of a tsunami earthquake. We performed dynamic rupture simulations using simplified fault models and the mechanism of thermal fluid pressurization. We found that small fluctuations of initial shear stress near a trench, within 1 MPa, lead to differences in seismic moment release greater than two orders of magnitude. In addition, we performed another experiment varying rupture nucleation sizes and obtained similar acute sensitivities of parameters. Moderate slip events with trapezoidal (flat‒topped) source time functions appear to occupy a transition position, between shallow megathrust earthquakes with surface rupture and smaller ordinary earthquakes without surface rupture. We interpret this result as representing the differences in interplate slip between shallow megathrust earthquakes, tsunami (moderate) earthquakes, and non‒tsunami (ordinary) earthquakes, on the basis of seismic observations.

Interplate thrust earthquakes are usually followed by afterslips, and they let the fore-arc move slowly trenchward. However, we do not know if the subducting oceanic plate is accelerated landward after such earthquakes. The westward velocity of Global Positioning System (GPS) stations in NE Japan show gradient decreasing from east to west reflecting the E-W contractional strain built up by the inter-plate coupling. Here we show that such coupling significantly enhanced (∼1.5 times) after the 2003 Tokachi-Oki earthquake (Mw 8.0), Hokkaido, in the segments adjacent to the ruptured fault. The coupling seems to be further enhanced (∼3 times) after the 2011 Tohoku-Oki earthquake (Mw 9.0). It is unlikely that interplate friction suddenly increased over such a large region, and relatively strong pre-2003 coupling there would not allow such enhancements even if full coupling is attained. Hence they are attributable to the temporary acceleration of the Pacific Plate subduction. We propose a simple 2-dimensional model in which down-dip acceleration of the slab let the force balance rapidly recover promoted by a thin low-viscosity layer on the slab surface. The accelerated subduction would account for temporary activations of regional interplate seismicity after megathrust earthquakes.

We discuss elastostatic effects on Mt. Fuji, the tallest volcano in Japan, due to historic earthquakes in Japan. The 1707 Hoei eruption, which was the most explosive historic eruption of Mt. Fuji, occurred 49 days after the Hoei earthquake (Mw 8.7) along the Nankai Trough. It was previously suggested that the Hoei earthquake induced compression of a basaltic magma reservoir and unclamping of a dike-intruded region at depth, possibly triggering magma mixing and the subsequent Plinian eruption. Here, we show that the 1707 Hoei earthquake was a special case of induced volumetric strain and normal stress changes around the magma reservoir and pathway of Mt. Fuji. The 2011 Tohoku earthquake (Mw 9), along the Japan Trench, dilated the magma reservoir. It has been proposed that dilation of a magma reservoir drives the ascent of gas bubbles with magma and further depressurization, leading to a volcanic eruption. In fact, seismicity notably increased around Mt. Fuji during the first month after the 2011 Tohoku earthquake, even when we statistically exclude aftershocks, but the small amount of strain change (