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We introduce an extended SEIR infectious disease model with data assimilation for the study of the spread of COVID-19. In this framework, undetected asymptomatic and pre-symptomatic cases are taken into account, and the impact of their uncertain proportion is fully investigated. The standard SEIR model does not consider these populations, while their role in the propagation of the disease is acknowledged. An ensemble Kalman filter is implemented to assimilate reliable observations of three compartments in the model. The system tracks the evolution of the effective reproduction number and estimates the unobservable subpopulations. The analysis is carried out for three main prefectures of Japan and for the entire country of Japan. For these four communities, our estimated effective reproduction numbers are more stable than the corresponding ones estimated by a different method (Toyokeizai). We also perform sensitivity tests for different values of some uncertain medical parameters, like the relative infectivity of symptomatic/asymptomatic cases. The regional analysis results suggest the decreasing efficiency of the states of emergency. [ABSTRACT FROM AUTHOR]

Interferometric synthetic aperture radar (InSAR) and global positioning system (GPS) have obvious deficiencies for monitoring surface deformations, for example, 1-D line-of-sight (LOS) measurements for InSAR and spatially very sparse observations for GPS. In this paper, InSAR and GPS measurements are integrated to derive spatially high-resolution 3-D coseismic surface displacement fields of the 2011 Mw 9.0 Tohoku-Oki, Japan earthquake. A unified simultaneous least squares (USLS) approach is developed to minimize the inconsistence between the InSAR results from adjacent paths. 3-D ground displacements are then derived by integrating the InSAR and the GPS measurements with the method of weighted least squares (WLS). Comparisons with independent GPS measurements show that the root mean square errors (RMSEs) of the derived 3-D displacements are 6.30, 4.57 and 1.29 cm for the vertical, east and north components, respectively. The 3-D coseismic displacement map shows that the Honshu Island moved eastwards towards the epicentre and subsided in the eastern part. The maximal displacements in the vertical, east and north directions are −1.5, 5.0 and −2.0 m, respectively. The effects of the density of GPS sites on the InSAR/GPS integration are also investigated. The experimental results reveal that lower to 70 km spatial resolution's GPS observations are adequate to guarantee the accuracies of the 3-D displacements for the Tohoku-Oki earthquake. This demonstrates the applicability of the developed WLS-based InSAR/GPS integration method, as in general the GPS observations are not as dense as those in this study area. Based on the spatially high-resolution 3-D surface displacement fields, we estimate the high-resolution and 3-D strain of the Tohoku-Oki earthquake. The preliminary results show that the Honshu Island suffers from an evident dilatation and shear during the seismic event. [ABSTRACT FROM AUTHOR]

Ben Cao Quan is an ancient classic book on materia medica compiled by Goku Yoshida, a Japanese scholar in the Edo period (1603-1867). A total of 568 materia medica in 53 categories in Ben Cao Quan came from Ben Cao Gang Mu compiled by Li Shizhen in the Ming Dynasty. These materia medica were introduced with some of his own interpretations of Goku Yoshida. The main characteristics of Ben Cao Quan reflected as follows. It attached importance to the comparison of translation from Chinese into Japanese and selected those materia medica commonly used in Japan, in particular, from 'spicific explanation' (Ji Jie) and 'smell' (Qi Wei) in Ben Cao Gang Mu .It focused on application and integrated local practice, and interpreted the personal insights of Goku Yoshida.Goku Yoshida's personal understanding and perception of these material medica were shown in terms of their origin and quality, analysis of their properties and collection, interpretation of their identification and selection, their local names, their Japanese names, and review of the changes when these materia medica were introduced into Japan.The purpose of Ban Cao Quan was to attempt to help Japanese identify materia medica and distinguish quality and interpret materia medica with Japanese characteristics. The book is valuable literature for the research of the impact of Ben Cao Gang Mu on the development of materia medica in Japan.

Purpose: Altered expression of microRNAs contributes to invasion and metastasis of many human cancers; however, the importance of microRNAs in head and neck cancers remains to be elucidated. In this study, we examined whether altered microRNA (miR)-551b expression correlated with invasive phenotypes of human oral squamous cell carcinoma (OSCC) in vivo and in vitro., Materials and Methods: Real-time polymerase chain reaction was used to detect the expression level of miR-551b in 71 OSCC tissues with lymph node metastasis and 50 nonmetastatic OSCC tissues. We also constructed miR-551b mimic-transfected cell lines HN4 and HN12. The effects of overexpressing miR-551b on the proliferation, migration, and invasion of OSCC cells were examined using Cell Counting Kit 8 (Dojindo, Kumamoto, Japan), plate clone formation, wound healing, and Transwell invasion experiments (Corning, Corning, NY). The association between clinical pathologic parameters and the expression level of miR-551b was analyzed using Kaplan-Meier survival analysis., Results: The expression of miR-551b measured 0.33 ± 0.11 in the 71 OSCC tissues with lymph node metastasis versus 0.54 ± 0.06 in the 50 tissues with non-lymph node metastasis (P = .021). Regarding OSCC patients, the expression of miR-551b negatively correlated with patients' overall survival (P = .035). The ectopic expression of miR-551b inhibited the invasion and migration of OSCC cells., Conclusions: This is the first report showing that reduced miR-551b expression may be an event leading to OSCC invasion and metastasis., (Copyright © 2020 The Authors. Published by Elsevier Inc. All rights reserved.)