In this study, we examined the phylogeny of Prunus, including an expanded sampling of species from tropical regions in Southeast Etomoxir Metabolism inhibitor Asia and the Americas, using sequences from four plastid markers and the nuclear ribosomal ITS region. A penalized likelihood method was used to estimate the absolute age of Prunus and the timing of infrageneric cladogenic events. The geographic origin of Prunus and

ancestral sites of cladogenesis were inferred using the Bayes-DIVA approach. Our results indicate that the modern genus appeared similar to 61 Myr in eastern Asia and that diversification of all major lineages may have been triggered by the global warming period of the early Eocene. In addition, our molecular dating estimates suggest that the crown clade that includes the temperate deciduous crop species is older than the one that includes the tropical evergreen species, while incongruence

between plastid and nuclear phylogenies suggests that the latter lineage originated via an ancient hybridization event. The most recent common ancestor (MRCA) of the temperate crop species was a component of the continuous boreotropical forests of the Northern Hemisphere, while the MRCA of the tropical species represented the last remains of GSK923295 the boreotropical elements and subsequently radiated throughout the Old and New World tropics from refugial areas at lower latitudes. Complex biogeographic histories leading to the present global distribution of the genus were driven by several geologic events, climatic oscillations, and independent dispersals across continents via the Bering and the North Atlantic Land Bridges during find more different geologic time periods. (C) 2014 Elsevier Inc. All rights reserved.”
“Slope

instability and foundation liquefaction caused by earthquakes are important research issues in geotechnical earthquake engineering. To analyse the effect of foundation liquefaction on the laws of slope acceleration, deformation and stability, the dynamic slope responses to a saturated foundation are studied and compared using nonlinear dynamic finite element methods based on the equivalent viscoelastic constitutive and elastic plastic constitutive models. The influence of a saturated foundation on the characteristics of dynamic pore pressure in the foundation, seismic acceleration and slope deformation is verified and analysed using a dynamic centrifuge model test. The dynamic pore pressure in the foundation greatly increases and results in foundation liquefaction. Therefore, heavy slope deformation caused by foundation liquefaction has a strong effect on slope instability during an earthquake. In addition, the dynamic true-coupled consolidation method is found to be superior to the quasi-coupled consolidation method.