Abstract: A startup stage protection device used in Electric Multiple Unit (EMU) train coupler experiment is provided between two test cars. The startup stage protection device is arranged between and tightly abuts two test cars at the starting stage of the experiment to receive a compressing force in place of the coupler. The startup stage protection device separates from the two test cars after the end of the starting stage.

Abstract: While genetic engineering has undergone rapid advancement with the discovery of CRISPR/Cas9, there is room for improvement for genetic circuit control, precision (reducing circuit ‘leakiness’) and delivery into living systems. The claimed invention offers programmable and precise regulation of dCas9 functions in response to multiple molecular signals by using synthetic gene circuits, greatly expanding applications. Moreover, using the system to greatest therapeutic potential has been greatly limited by the restrictive cargo size of existing viral delivery systems. By splitting dCas9 into multiple sections, the delivery size of synthetic gene circuits is greatly reduced. By exchanging split dCas9 domains, differential regulation on one gene, or activating two different genes in response to cell-type specific microRNAs is illustrated.