The Fungal X-rays are an optional artifact in the university science building. After you follow Ellie through the short tunnel, turn left and check the far table next to the window.
Scans of a patient's head and neck with fungal growth visible in the brain. The skull shape suggests the subject was at the stalker stage of infection.
It is evidence that the Fireflies were studying infected patients in this lab, part of the research Ellie was meant to help.
Firefly's recorder
The Firefly's recorder is an automatic artifact in the university science building. Joel picks it up from a dead Firefly in a cutscene, so it cannot be missed, and you can play the whole message later from the Artifacts menu.
Free Radicals
Free Radicals, issue 7 of Savage Starlight, is on the rusty hood of a car up the hill behind you as The University begins.
Griggs's Firefly Pendant
Griggs's Firefly pendant lies on a table in the last tent of a camp outside the science building, in the Go Big Horns section of The University. It belonged to Erik Griggs.
H. Pino's Firefly Pendant
H. Pino's Firefly pendant hangs from a tree near the flamethrower room in the Go Big Horns section of The University. It belonged to Hope Pino and needs knocking down.