The use of restriction enzymes as a tool for recombining, or joining, different DNA fragments was first illustrated in yet another classic paper, this time by Stanford University researchers Janet Mertz and Ronald Davis (Mertz & Davis, 1972).
Averages for Puerto Vallarta in February. The temperatures are still very warm in Puerto Vallarta, Mexico, in February, even though itâs still winter. Thanks to the cityâs location close to the equator, it enjoys good weather all year round providing the perfect place to head for a winter beach break â it certainly beats the cold European winter.
Weather lowdown. September may well be one of the hottest months in Puerto Vallarta, Mexico, but itâs also the wettest. Thanks to the cityâs location close to the equator, it experiences a tropical climate complete with dry and rainy seasons.