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.
The term RNA interference (RNAi) was coined to describe a cellular mechanism that use the gene's own DNA sequence of gene to turn it off, a process that researchers call silencing.In a wide variety of organisms, including animals, plants, and fungi, RNAi is triggered by double-stranded RNA (dsRNA).he term RNA interference (RNAi) was coined to describe a cellular mechanism that use the gene's own DNA sequence of gene to turn it off, a process that researchers call silencing.