In this paper,in the case of upper protective layer mining of a mine for the engineering background, based on the model of semi-infinite plane body in elastic mechanics, the theoretical calculation model of vertical, horizontal, shear stress of floor coal rock is established, and it is concluded that the stress expression of any point in the impact of distributed force. By introducing the rock strength index I and generalized Hooke's law, it is concluded that the discrimination criterion of guide gas fissure zone and pressure relief desorption belt of underlying coal rock with upper protective layer mining. The pressure relief scope of protection with the mining of upper protective layer is determined. Theoretical analysis shows that: the "pressure relief desorption zone" of the underlying protected coal seam that the vertical distance to the protective layer is 40m lags behind 22.2m.Through field test, the results show that the obtained pressure relief scope of protection is 26.98m,and the theoretical analysis results are basically similar.

Adult mammalian heart repair after myocardial damage is highly inefficient due to the post-mitotic nature of cardiomyocytes. Interestingly, in traditional Chinese medicine (TCM), there are reported effective treatments of myocardial infarction (MI) and heart failure in adult humans by oral intake of a TCM concoction named Gu Ben Pei Yuan San (GBPYS), which is composed of Panax ginseng, velvet antler, Gekko gecko Linnaeus tail, human placenta, Trogopterus dung, Panax notoginseng, and amber. We fed mice with GBPYS after myocardial damages through everyday self-feeding. We then examined the effect of everyday oral intake of GBPYS on improving cardiac function and myocardial repair in adult mice after apical resection or MI. We found that long-term oral intake of GBPYS significantly improved cardiac function after myocardial damages in adult mice. BrdU, phospho-histone 3, and AuroraB staining indicated increased cell proliferation at the border zone of MI after TCM feeding. GBPYS feeding reduced organ inflammation, induced angiogenesis, and is non-toxic to mice after long-term oral intake. Further, serum derived from TCM-fed MI rats promoted division of both neonatal rat cardiomyocytes and human induced pluripotent stem cell (iPSC)-derived cardiomyocytes in vitro. Oral intake of GBPYS improved heart repair after myocardial damages in adult mice. Our results suggest that there are substances present in GBPYS that help improve adult mammalian heart repair after MI. Also, it could be a good choice of non-invasive alternative therapy for myocardial damages and heart failure after rigorous clinical study in the future.

Abstract The chemical compositions of blue and white Chinese Jingdezhen porcelain samples were analysed using energy-dispersive x-ray fluorescenceorescence (EDXRF) techniques. The results were subjected to multivariate statistical analysis. Different compositional patterns were found for specimens from different periods (Yuan, Ming and Qing dynasties) and for different intended usage (imperial or common). The reasons for these variations are discussed. From the analysis a discriminant function is generated that is capable of classifying samples with high efficiency. Copyright © 2000 John Wiley & Sons, Ltd.

The chemical compositions of blue and white Chinese Jingdezhen porcelain samples were analysed using energy-dispersive x-ray fluorescence (EDXRF) techniques. The results were subjected to multivariate statistical analysis, Different compositional patterns were found for specimens from different periods (Yuan, Ming and Qing dynasties) and for different intended usage (imperial or common). The reasons for these variations are discussed. From the analysis a discriminant function is generated that is capable of classifying samples with high efficiency. Copyright (C) 2000 John Wiley & Sons, Ltd.