While it is relatively easy to define what a hurricane or earthquake is, defining a drought is more subjective. Droughts do not have the immediate effects of floods, but sustained droughts can cause economic stress throughout an area. The word drought has various meanings, depending on a person's perspective.
For the software package, see Partition function for Interacting RNAs. Piwi-interacting RNA (piRNA) is the largest class of small non-coding RNA molecules expressed in animal cells. piRNAs form RNA-protein complexes through interactions with piwi proteins.
An RNA virus is a virus that has RNA (ribonucleic acid) as its genetic material.This nucleic acid is usually single-stranded RNA (ssRNA) but may be double-stranded RNA (dsRNA).n RNA virus is a virus that has RNA (ribonucleic acid) as its genetic material. This nucleic acid is usually single-stranded RNA (ssRNA) but may be double-stranded RNA (dsRNA).