Reverse transcriptase is characteristic of retroviruses, including HIV (human immunodeficiency virus), the virus responsible for AIDS (acquired immunodeficiency syndrome). All retroviruses encode a polymerase enzyme in their pol gene that is both necessary and sufficient for the replication of their RNA genomes.
PDO positive phase global pattern. The Pacific Decadal Oscillation (PDO) is a robust, recurring pattern of ocean-atmosphere climate variability centered over the mid-latitude Pacific basin.
The cool phase of ENSO is called  La Nina  niÃ±a WITH sst in the Eastern pacific below average and air pressures high in the eastern and low in Western. Pacific THE enso, cycle Both El nino NiÃ±o And, la nina niÃ±a causes global changes of both. Temperatures and rainfall mechanisms that cause the oscillation. remain under studyl Nino NiÃ±o Southern oscillation refers to the cycle of warm and cold, temperatures as measured by sea surface, TEMPERATURE, sst of the tropical central and Eastern Pacific. ocean