It seems they use liquid nitrogen to cool the iris. While it is very cold, water is a far more efficient coolant.
About 35 minutes, Apophis' blood pressure is visible in the ER. Although he is in enormous pain, his human (host) body has a normal blood pressure in the 120/80 range. This is ridiculously low for someone in so much pain. Both numbers should be far higher.
Daniel tells General Hammond that he has an idea to stop the Gou'ald from reopening a wormhole to the SCG by dialing out and keeping their gate open. Both Daniel and Hammond act like this is a brilliant, original idea when in fact they have done this before in a previous episode.
However, the previous episode was There But for the Grace of God (1998), which took place in an alternate universe, in which Daniel witnessed an alternate Samantha Carter program the gate to dial faster. It is still a valid quibble to ask why Daniel didn't detail this in his report of the alternate reality incident, so the SGC would know about the Gould strategy to keep a gate open for an attack and Carter's ability to speed up dialing.
However, the previous episode was There But for the Grace of God (1998), which took place in an alternate universe, in which Daniel witnessed an alternate Samantha Carter program the gate to dial faster. It is still a valid quibble to ask why Daniel didn't detail this in his report of the alternate reality incident, so the SGC would know about the Gould strategy to keep a gate open for an attack and Carter's ability to speed up dialing.
Although the patient on the table was Apophis, at 35 minutes the view of the monitor shows the words "Patient Carter, Jacob" who is Samantha Carter's father.
When Apophis is screaming in pain, a mouth full of fillings can clearly be seen.