Hairworks hardware dependecies

Hello.

I just discovered the HairWorks tools here (https://developer.nvidia.com/hairworks), and found it very powerful.

But I have a simple question (I’m new here please forgive my newbe angle), does it require a Nvidia graphic card to work, as it is a middleware solution ?
For example, does ATI Radeon could run HairWorks ?
I didn’t have any in my whole life but it seems they can run PhysX-powered games right ?

I just read the blog post about HBAO+'s Gameworks and Unity3D gateway :

Did something like that can occur with hairworks ?