add a comment |. up vote 1 down vote. If a game has a value, it need not to have a mixed strategy Nash equilibrium. In the Von Neumann's Minimax theorem stated above, it is assumed that, for each player, the set of mixed strategy best responses is nonempty given the other player's mixed strategy.
Not all RNA viruses are retroviruses, e.g., the measles virus and flu virus are RNA viruses, but not retroviruses. There are three families of retroviruses: oncoviruses (causing cancer), lentiviruses (slow viruses, of which HIV is one), and foamy viruses or spumaviruses (about which much less is known).
A retrovirus is a single-stranded positive-sense RNA virus with a DNA intermediate and, as an obligate parasite, targets a host cell. Once inside the host cell cytoplasm, the virus uses its own reverse transcriptase enzyme to produce DNA from its RNA genome, the reverse of the usual pattern, thus retro (backwards). The new DNA is then incorporated into the host cell genome by an integrase enzyme, at which point the retroviral DNA is referred to as a provirus.