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.
RNAi (RNA interference) defined. RNA interference (RNAi) is a natural process that cells use to 'turn off' or silence unwanted or harmful genes.The initial discovery of this phenomenon was in 1991, by scientists trying to deepen the colour of petunias. Surprisingly, by introducing a gene for colour, they found that they had turned off the gene.NA interference (RNAi) is a natural process that cells use to 'turn off' or silence unwanted or harmful genes.