They also found other sets of genes that were not originally important for diversification of form and function, that later became important in reducing the viability of hybrids. (sciencedaily.com)
Additionally, research suggests that frozen eggs do not suffer from reduced viability or other negative effects when they are stored for up to four years. (vcrmed.com)
The option of using substitute natural gas in combined heat and power distributed generators further reduces the viability of any investment in coal - fired plants. (euractiv.com)