Basically, she is interested in sensor and monitoring circuits. Extremely specific set of interests. In principle, an amplifier is an amplifier. The parameters needed for the amplifier drive you to search out components or methods that fit those parameters. Such as a gallium azide mosfet for solid state microwave (or to develop theories for new models of microwave mosfet). It's unusual to see someone with an ultrasound amp fetish.
Unless she was aiming at a specific industry field and tailoring her profile to help when they plugged her name in. Makes more sense when looked at, that way. As if she is trying to appeal to a specific industry.
So… For that… Possibly medical field as a biomed for their ultrasound equipment. Most likely. Other options are directed sound equipment which use phased array transducers like an AESA radar. Just with sound. Harmonics and interference patterns generate sound in the audible frequencies along a defined vector or even area in 3d space. Not as likely. Missing FPGA and programming for that.