When does a plaintiff's deliberate indifference claim survive summary judgment?

In Leavitt v. Corr. Med. Serv. Inc. , 645 F.3d 484 (1st Cir. 2011), the U.S. Court of Appeals for the First Circuit reviewed the decision of the U.S. District Court, District of Maine regarding a plaintiff's 42 U.S.C. § 1983 (2000) action alleging a violation of his Eighth Amendment rights for