【简答题】Later, engineers _______(manage) to construct railways in a system of deep tunnels ( 隧道) , which became known to the Tube. This development was only possible with the introduction of electric-powered ...
【单选题】A pair of synthetic gene circuits that count events — a long-stated goal for circuit engineers — was reported in _______. For one of these counter circuits, recombinase-mediated DNA rearrangement was ...