Santa's Little Helper for "The Tampa Tribune" listed Santa's Little Helper at number six, writing: "We admire his upbeat nature even after having his legs broken by Mr. Burns and being abandoned by Bart for another dog, Laddie." He also ranked 75th on Retrocrush author Robert Berry's list of "The 100 Greatest Dogs of Pop Culture History" in 2006. The character has attracted some criticism too, though. While reviewing the episode "Bart's Dog Gets an F" in 2010, Nathan Rabin of "The A.V. Club" wrote: "As cartoon dogs go, Santa’s Little Helper is spectacularly unspectacular. In a realm of aggressively anthropomorphic canines, some
Helper dependent virus and capsid encoding DNA, plus helper DNA. Every cell that is successfully transfected with all three DNA fragments will produce the necessary proteins to produce infective viruses. These viruses will only have transgenic DNA encapsidated and therefore once they've infected a patient's cell, they will not be capable of reproducing. Helper dependent viruses can also occur in nature without being "gutted". The term satellite virus has been given to a large group of viruses that all require the presence of another virus to replicate. Many of these are plant viruses, but animal viruses can be seen in the case of