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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]

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]

This paper describes the topographic change and the recovery process, as well as the sediment sources, for tsunami deposits based on field surveys and analysis of digital elevation model data before and after the A.D. 2011 Tohoku-oki tsunami at the Sendai Plain, Japan. We found that the amount of sediment deposited on land was approximately four times greater than the eroded volume of sediment at the beach. Large amounts of the sediments deposited at the studied transect probably originated from liquefaction. This result suggests that the vented sediments might have been an important source of the tsunami deposits if liquefaction is generated by the strong ground motion of a near-field earthquake. In contrast, minor erosion was observed at the beach, and the beach berm was rebuilt within three months after the tsunami. Moreover, the erosional channel that had cut into the beach had been filled by sand within 13 days after the tsunami. Therefore, it is not expected that a sedimentary record of the tsunami will be preserved in the nearshore zone along the Sendai coast, although remnants of small scours on land might remain long after the tsunami. [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]