Setting Up Custom Signals for Clinical Trial Sales in Clay

I'm planning to use Clay working as a salesperson at a new company (Clinical Trial AI space, which I hope gives some context to the signals I'm looking for). Could someone help me out? I'm trying to get some signals set up. Doing new job listings was easy enough, but what if I wanted to do something custom like "In the last week did this account announce that they're starting a new clinical trial" (if running weekly) or "In the last week has this account posted or been mentioned in a post announcing that they're adding a new site to their site network" etc. Thanks a bunch!