We've already mentioned such subjects as ion-channels, neurotransmitters, synapses and vesicles. You might be forgiven for failing to recognize the underlying subject in this prose about SNARE proteins, smart valves and communication within/between cells. I recognized this only because I had realized that every time biochemicals are released from vesicles inside a cell this is the result of membrane fusion, typically associated with calcium channels. This is really fundamental biology, and it seems previous work had left us in the dark about just how active those ion-channels or pores really were. Understanding is changing so much I expect there will be even newer terminology in future papers, to distinguish them from past work based on assumptions which have now been falsified.