I think it's alright. Expression is nice and she looks relaxed and engaged on the whole. With the exception of her arms as mentioned; left looks a little straight and locked and her right is kind of just hanging there.
Exposure I don't mind, maybe a tiny bit too hot in places. But then I generally 'overexpose' portraits myself. I too find the reds a bit overcooked as Ryan mentioned.
I think you could give the framing a bit of work. She feels a bit lost in the corner, to my eye. A slightly lower viewpoint looking up more would have reduced the headroom, and tidied up the bottom of the frame where you have those blue doors peaking in and the dead space under the bench.
Besides the framing, I think the background and depth of field are fine. Plenty of context without being distracting. Possibly with the exception of the black power leads, particularly the one on the left close to her head. Again, a slightly lower viewpoint looking back up would have moved the plugs down and away from the line of her face; which would have made them less distracting.
And yes, her lab coat looks a bit sloppy.
Edit to add: I also prefer the shot of her by the microscope. Though again I would've shot slightly lower and looking back up for framing the background, and got rid of a couple of the black power leads - particularly the one edge of frame on the right.