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.
Declination (delta): angular distance from the celestial equator (+=north, -=south). Right Ascension (alpha): angular distance along circles parallel to the equator. Define zero point to be the vernal equinox, the point where the Sun's position crosses the celestial equator as it moves north. Right ascension increases going eastward. Dec is measured in degrees, minutes of arc, seconds of arc, or decimal degrees.