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Offshore wind turbines in regions of active seismicity are under a potential threat caused by the joint earthquake and ocean wave action. Taking NREL-5MW monopile wind turbine as the prototype, this study is devoted to probe the joint action of strong earthquakes and moderate sea conditions. A series of shake table model tests of scale 30:1 have been carried out by the contemporary world unique facility (Earthquake, Wave and Current Joint Simulation System) to investigate the structural response in dry flume, low and high calm water levels, with and without regular or random waves. Particular interest has been in the nacelle acceleration subjected to strong ground motions as well as to random waves. The experimental results of nacelle peak accelerations and corresponding dynamic amplification factors show that the joint earthquake and wave action is important for the proper evaluation of structural response. Ignoring the effect of wave action in seismic analysis will lead to underestimation of structural response, especially when the monopile foundation is dynamically sensitive. The coupling of earthquake and wave actions is sourced not only from the relative velocity of vibration but also from the initial condition induced by waves. It has been also derived that the peak acceleration excited by a moderate sea condition is comparable to that by a moderate earthquake. [ABSTRACT FROM AUTHOR]

In this paper, the notion of affinelike set-valued maps is introduced and some properties of these maps are presented. Then a new Hahn–Banach extension theorem with a K-convex set-valued map dominated by an affinelike set-valued map is obtained. [Copyright &y& Elsevier]

The small molecule STM2457, a selective inhibitor of m6A methyltransferase METTL3, holds considerable potential for cancer therapy. In this paper, a chromatography-free synthesis of STM2457 featuring inexpensive raw materials and easy synthetic manipulations is presented. [Display omitted] STM2457, a potent and selective inhibitor of m6A methyltransferase METTL3, is a first-in-class drug candidate for cancer therapy. Herein, we present a chromatography-free synthesis of STM2457 in nine steps and 32% overall yield. In comparison to the reported route, the current approach features inexpensive raw materials, gentle reagents and simple experimental manipulations. We expect the present work supports the production of STM2457 and facilitates its therapeutic applications. [ABSTRACT FROM AUTHOR]