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Abstract: This paper focuses on the relationship between the maximum extent of sandy tsunami deposits and inundation distance of the 2011 Tohoku-oki tsunami. Inundation limits of the Tohoku-oki tsunami were assessed over seven shore-normal transects along the Sendai Coastal Plain. Inundation distances were found to range from 0.6 to 4.0km. At the maximum extent of the tsunami deposit, the sand unit ranged in thicknesses from 0.1 to 4.0cm. The maximum limit of the ≥0.5cm thick sand layer extended to over 90% of the inundation distance where the inundation distance was less than 2.5km. This observation is consistent with previous studies that examined characteristics of recent tsunami events that had inundation distances of at least 2km. The maximum limit of the ≥0.5cm thick sand layer extended to 3km (57–76% of the inundation distance) where the inundation distance was more than 2.5km. Our results are important for estimating paleo-tsunami inundation distances based on the landward extent of sand deposits and valuable for the assessment of future tsunami risks in other coastal areas in the world, which have been devastated by huge tsunamis in the past. [Copyright &y& Elsevier]

Ischemia-reperfusion injury causes oxidative stress producing reactive oxygen species, which is a serious problem linked to morbidity and mortality in liver surgery. We investigated the effects of edaravone, a new free radical scavenger, on liver oxidative stress in vitro and in vivo. We employed a hypoxia-reoxygenation model of primary cultured hepatocytes using an AnaeroPack (Mitsubishi Gas Chemical Co., Tokyo, Japan). Hepatocytes were exposed to 3 or 4 hours of hypoxia and then returned to oxygenation. We analyzed the time course changes of aspartate aminotransferase (AST), phosphatidylcholine hydroperoxide (PCOOH), and adenosine triphosphate (ATP) content in hepatocytes of edaravone-treated groups or nontreated groups after reoxygenation. Edaravone significantly attenuated the elevation of the AST level of the medium and hepatocellular PCOOH and preserved the hepatocellular ATP level. In vivo, male Sprague–Dawley rats were subjected to 45 minutes of hepatic ischemia and 120 minutes of reperfusion. The rats were intravenously injected with vehicle or edaravone (3 mg/kg or 10 mg/kg) before reperfusion and 1 hour after reperfusion. Serum AST levels and hepatic PCOOH and energy charge were significantly improved in both edaravone groups compared with control. In conclusion, edaravone has the ability to eliminate intra-hepatocellular superoxide species and attenuate oxidative liver damage in liver surgery. [Copyright &y& Elsevier]

Ongoing climate change has increased the impact of landslides and related slope disasters on infrastructure and human lives. Microwave satellite remote sensing, particularly interferometric analysis of synthetic aperture radar (InSAR) data, is a powerful tool for routine monitoring of the displacement of slopes on small wavelength scales, independently from solar illumination and cloud coverage. Although various sophisticated techniques for time-series InSAR have been developed, practical application in conjunction with geological analysis to reveal intrinsic and triggering factors of slope displacement is still limited. In this paper, we describe a practical case of time-series InSAR analysis with a special focus on its geological implications in northwestern Kyushu, a high-risk area for slope-related disasters in Japan. The extracted susceptible polygons from the InSAR results show accuracy comparable with that of other recent research on landslide mapping. Intrinsic factor analysis based on a geographic information system reveals that the displacement occurs on relatively gentle slopes instead of steep areas, corresponding to the transient zone of Paleogene-Neogene sedimentary rocks and basalt. Triggering factor analysis based on correlation coefficients reveals a significant link between some displacement areas with mean and/or maximum precipitation for each observation duration. Those findings confirm the importance of carefully accounting for the geological background for landslide susceptibility assessment and policy making, apart from topographic and meteorological conditions. [ABSTRACT FROM AUTHOR]

• Sleep deprivation (SD) has been shown to decrease cognitive function. • We evaluated the acute effectiveness of exercise on cognitive function after SD. • Cognitive function was measured using a color word Stroop task. • Exercise can improve cognitive function after SD. We evaluated the effects of moderate-intensity exercise in improving the decline in cognitive performance induced by a 24-h period of acute sleep deprivation (SD). We hypothesized that the positive effect of exercise is mediated by increased oxygenation (measured using near-infrared spectroscopy) of the dorsolateral prefrontal cortex (DLPFC). Cognitive performance was measured using the reaction time and interference scores of the Stroop colour and word test, in 12 healthy adults (eight males, 21.1 ± 0.3 years-old), at pre- and post-exercise. Cognitive scores were compared under two conditions: rested wakefulness (RW) and 24-h SD. The exercise consisted of 20-min of ergometer cycling at an intensity of 60 % VO 2peak. Oxygenation to the DLPFC increased, at 12 min after exercise onset, compared to the baseline and was maintained until the end of the exercise in both RW and SD conditions (P < 0.01). The change in RT correlated with sleepiness (P < 0.05), with no correlation for the interference score and oxygenation. Taken together, moderate-intensity exercise reverses SD-induced cognitive decline. [ABSTRACT FROM AUTHOR]

Valganciclovir (VGCV) has been shown to improve sensorineural hearing loss (SNHL) and neurological outcomes in patients with neonatal symptomatic congenital cytomegalovirus (cCMV) infection. However, reports on the pharmacokinetics, efficacy and safety of oral VGCV are limited. The aim of this study is to evaluate the pharmacokinetics of VGCV for use in the treatment of cCMV. This was a single-center, retrospective observational study conducted at Saitama Children's Medical Center in Japan between 2012 and 2017. CMV DNA copy number, maximum plasma VGCV concentration (Cmax), and adverse events (ADEs) during treatment were evaluated. A total of 26 patients with cCMV who received VGCV were included in this study. The median age at VGCV initiation was 9.5 months (range 0–46). Twenty-one patients (81%) had SNHL at baseline. Of these, five patients (19%) presented with improved SNHL, and none experienced worsened SNHL during treatment. The mean VGCV Cmax was 3.5 μg/mL (range 2–5.3), with no significant variation among individual values, and the values were maintained during treatment. Furthermore, there were no correlations between the Cmax values and age, sex, SNHL improvement or ADEs. Neutropenia (<1000/mm3) was observed in six patients (23%); however, no serious ADEs occurred. VGCV prevented the progression of SNHL without serious ADEs due to its stable pharmacokinetics. This study provides safety and tolerability of VGCV for the treatment of cCMV patients. [ABSTRACT FROM AUTHOR]

Soon after the 2011 Tohoku-oki event, approximately 1300 tsunami deposit thickness data were collected spatially by the governors to cover the entire tsunami affected area (Sendai Plain) along the Sendai Bay coastline. This dataset, along with high-resolution and high-precision data of flow depth and pre-tsunami and post-tsunami elevation, enables us first to conduct a direct comparison of the sedimentation and erosion volumes as well as the tsunami hydrodynamic features (e.g., flow depth) and sediment thickness. The total balance of sedimentation and erosion volumes revealed that the volume of tsunami-deposited sediments can be explained roughly using the erosion volumes at the beach and sand dunes for sandy deposits and at rice paddy fields for muddy deposits. Both the flow depth and sediment thickness showed positive correlations with the distance from the shoreline while sediment thickness is no correlation to the elevation except in the zone closest to the shoreline where erosion is present. In addition, a statistical relation was found between the flow depth and sediment thickness. In fact, the frequency distribution of sediment concentration, defined here as the sediment thickness divided by the maximum flow depth at each survey site, fits well with the logarithmic normal distribution with geometric average of about 2%. This fit indicates that the tsunami deposits on the Sendai Plain can be explained generally if we simply assume that the saturated level of the sediment concentration in the flow is limited to about 2% on average, irrespective of the grain size. Such a simple explanation might be applicable only for the tsunami deposits on the Sendai Plain because the topography is remarkably flat and low. Therefore, the tsunami inundation process is relatively simple. Nevertheless, a possible relation between tsunami flow depth and sediment thickness suggested here would be very useful to consider the ideal sedimentary process of the tsunami deposits and to improve forward and inverse modelings. [ABSTRACT FROM AUTHOR]

The interaction between tsunami hydrodynamics and sediment behavior results in a complex depositional process for onshore tsunami deposits. Furthermore, the formation of modern tsunami deposits can be affected by artificial structures, which can make the depositional processes difficult to understand. In the present study, we focus on artificial structures to reveal the relationship between sedimentary structures and hydrodynamics of the 2011 Tohoku-oki tsunami. Field observations indicated that a coastal dike and three shore-parallel roadways significantly affected the source, thickness, and sedimentary structures of the tsunami deposits. The sandy tsunami deposits were mainly sourced from the backshore, which was severely eroded at the landward side of the dike by tsunami overflow. The thickness of the tsunami deposits increased seaward of roadways, while the deposit became thinner landward of roadways. A one-dimensional numerical simulation indicated a local decrease in the flow velocity at the seaward side of roadways, which elucidated the increase in the deposit thickness. Most tsunami deposits are characterized by normal graing, inverse grading, and ungraded units. Inverse grading was observed 0.05 km from the shoreline and at the seaward side of the roadways, except at the most landward roadway. Changes in the grain-size distribution of the deposits and variations in the simulated flow velocity across the roadways suggested that the inverse grading was formed because of waxing and depletive flow conditions with high concentrations of suspended sediments. Our study elucidated the key role that artificial structures play in the formation of tsunami deposits and the resultant sedimentary structures, in developed coastal areas. Artificial structures, which have a somewhat extreme topography compared to the natural geomorphology, also contributed to demonstrate the concept of the acceleration matrix. This is because of the remarkable change in the steadiness and uniformity of the tsunami flow and the resultant sedimentary structures. [ABSTRACT FROM AUTHOR]