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A new one-minute global seafloor topography model was derived from vertical gravity gradient anomalies (VGG), altimetric gravity anomalies, and ship soundings. Ship soundings are used to constrain seafloor topography at wavelengths longer than 200 km and to calibrate the topography to VGG (or gravity) ratios at short wavelengths area by area. VGG ratios are used to predict seafloor topography for wavelength bands of 100–200 km and to suppress the effect of crust isostasy. Gravity anomalies are used to recover seafloor topography at wavelengths shorter than 100 km. The data processing procedure is described in detail in this paper. The accuracy of the model is evaluated using ship soundings and existing models, including General Bathymetric Charts of the Oceans (GEBCO), DTU10, ETOPO1, and SIO V15.1. The results show that, in the discussed regions, the accuracy of the model is better than ETOPO1, GEBCO, and DTU10. Additionally, the model is comparable with V15.1, which is generally believed to have the highest accuracy. In the north-central Pacific Ocean, the accuracy of the model increased by approximately 29.5% compared with the V15.1 model. This indicates that a more accurate seafloor topography model can be formed by combining gravity anomalies, VGG, and ship soundings. [ABSTRACT FROM PUBLISHER]

To study the seismogeny process or the precursory behavior of the 1976 M S=7.0 Lijiang earthquake, we analyze the repeat gravity data with high precision from the Western Yunnan Earthquake Prediction Experiment Area (WYEPEA) and the related results of geology and geophysics survey in this paper. Considering the gross errors caused by observation data and model difference, we have firstly inverted the slip distribution of the main active faults with time based on the robust Bayesian least squares estimation and multi-fault dislocation model. The results show that the slip changes of the faults with time from 1990 to 1997 obviously reflect the preparation process of the Lijiang earthquake. The images of main precursor mode have the characteristic of main shock-after shock type, which is agreement to the model of coupling movement between crust density and crust deformation (DD mode of coupling movement). [ABSTRACT FROM AUTHOR]

Aim: To study the metabolic profile of human umbilical mesenchymal stem cells (HUMSC) and adipogenic differentiation by nuclear magnetic resonance (NMR) spectroscopy., Methods: HUMSC isolated from human umbilical cord stroma were induced to adipocytes over 2 wk by adding dexamethasone, 3-isobutyl-1-methylxanthine, indomethacin, and insulin to the culture medium. Adipogenic differentiation was confirmed by Red O staining and transcription-polymerase chain reaction. Perchloric acid extracts of the HUMSCs and adipocytes (about 7 × 10(6)) were characterized for metabolites by using in vitro high resolution 9.4T NMR spectroscopy., Results: Several major metabolites, such as: choline, creatine, glutamate and myo-inositol, acetate, and some fatty acids/triglycerides, were observed in the MR spectroscopic pattern of HUMSCs and their adipogenic differentiation. HUMSCs are characterized by an unusually low number of NMR-detectable metabolites, high choline, acetate, glutamate and creatine content. However, the metabolic profiles of adipogenic differentiation demonstrated considerably higher methionine and fatty acids, and non-detectable creatine., Conclusion: The biomarkers of HUMSCS and adipocytes were obtained and assigned. NMR spectroscopy will be a promising tool for monitoring stem cell differentiation.