Orbital- and millennial-scale Asian winter monsoon variability across the Pliocene–Pleistocene glacial intensification

Intensification of northern hemisphere glaciation (iNHG), ~2.7 million years ago (Ma), led to establishment of the Pleistocene to present-day bipolar icehouse state. Here we document evolution of orbital- and millennial-scale Asian winter monsoon (AWM) variability across the iNHG using a palaeomagnetically dated centennial-resolution grain size record between 3.6 and 1.9 Ma from a previously undescribed loess-palaeosol/red clay section on the central Chinese Loess Plateau. We find that the late Pliocene–early Pleistocene AWM was characterized by combined 41-kyr and ~100-kyr cycles, in response to ice volume and atmospheric CO2 forcing. Northern hemisphere ice sheet expansion, which was accompanied by an atmospheric CO2 concentration decline, substantially increased glacial AWM intensity and its orbitally oscillating amplitudes across the iNHG. Superposed on orbital variability, we find that millennial AWM intensity fluctuations persisted during both the warmer (higher-CO2) late Pliocene and colder (lower-CO2) early Pleistocene, in response to both external astronomical forcing and internal climate dynamics

RNA interference in Lepidoptera: an overview of successful and unsuccessful studies and implications for experimental design

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Research of protection for AC transmission lines based on characteristic of grid-side inverter

With the advantage of saving resources and high utilisation, DC transmission becomes the vital part of the sustainable development. However, due to the control strategies of grid-side inverter, the fault characteristics of the grid will change dramatically, which influences the reliability of grid protection. By establishing the model in PSCAD, the fault characteristics of the inverter was obtained and the effects on current protection was analysed here. The results reveal that the magnitude of fault current was directly influenced because of being connected with the inverter. The grid inverter can make a difference in selectivity and reliability of current protection. In order to solve this problem, the paper constructs the equivalent model of the inverter and attains the unique feature that the fault component impedance measured in the location of protection decreases with the increasing distance of fault location. According to the characteristics, a targeted fault component impedance protection is designed. The feasibility and effectiveness of this protection is verified by simulation in PSCAD model