The Fukushima Dai-ichi Nuclear Power Plant accident caused serious Cs contamination in mountainous forest areas. To understand the spatial variation in soil Cs inventory in complex mountainous topography and the influencing factors, a whole-area investigation of Cs deposition in a broad-leaved forest catchment of a mountain stream was conducted using grid sampling. Across the catchment, organic and surface mineral soil layers were collected at 42 locations in 2013 and 6 locations in 2015.
View Article and Find Full Text PDFThe source term of Cs from the Fukushima Dai-ichi Nuclear Power Station (FDNPS) accident was estimated from the results of local-scale atmospheric dispersion simulations and measurements. To confirm the source term's validity for reproducing the large-scale atmospheric dispersion of Cs, this study conducted hemispheric-scale atmospheric and oceanic dispersion simulations. In the dispersion simulations, the atmospheric-dispersion database system Worldwide version of System for Prediction of Environmental Emergency Dose Information (WSPEEDI)-DB and oceanic dispersion model SEA-GEARN-FDM that were developed by the Japan Atomic Energy Agency were used.
View Article and Find Full Text PDFTo assess the radiological dose to the public resulting from the Fukushima Daiichi Nuclear Power Station (FDNPS) accident in Japan, especially for the early phase of the accident when no measured data are available for that purpose, the spatial and temporal distributions of radioactive materials in the environment need to be reconstructed through computer simulations using the atmospheric transport, dispersion, and deposition model (ATDM). For the ATDM simulation, the source term of radioactive materials discharged into the atmosphere is essential and has been estimated in many studies. In the present study, we further refined the source term estimated in our previous study and improved the ATDM simulation with an optimization method based on Bayesian inference, which used various measurements such as air concentration, surface deposition, fallout, and newly released hourly air concentrations of Cs derived by analyzing suspended particulate matter (SPM) collected at air pollution monitoring stations.
View Article and Find Full Text PDFBackground: Chronic obstructive pulmonary disease (COPD) is characterized by airway inflammation with endothelial dysfunction. Cadherins are adhesion molecules on epithelial (E-) and vascular endothelial (VE-) cells. Soluble (s) cadherin is released from the cell surface by the effects of proteases including matrix metalloproteinases (MMPs).
View Article and Find Full Text PDF. This study aimed to examine whether plasma levels of cathepsin S or its inhibitor, cystatin C, may serve as biomarkers for COPD. .
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