In Dino Veritas, which aired before Post Traumatic Slide Syndrome on Fox (and later on Sci-Fi), was
originally intended to occur after PTSS. These observations are with this fact in mind.

In this episode, Arturo lied a lot more than anyone else did, and considerably so. He also asked to be left behind, something he started doing after PTSS quite often (probably out of guilt). The only thing that I had doubts about was that he seemed to remember "naked world" from Gillian of the Spirits. But, as he said in PTSS, "Anyone who has read Miss Wells' serialized diary" would have known that, especially since the sliders had been there after Luck of the Draw, which (as far as we know) was when Wade began keeping the diary. A world as unforgettable as that one would no doubt earn a detailed entry in her diary!

Just one of many evidences!