A debt-to-GDP ratio of 60% is quite often noted as a prudential limit for developed countries. This suggests that crossing this limit will threaten fiscal sustainability. For developing and emerging economies, 40% is the suggested debt-to-GDP ratio that should not be breached on a long-term basis.
1 Telomerase is found in high levels in germline cells (egg and sperm) and stem cells. 2  In these cells telomere length is maintained after DNA replication and the cells do not show signs of ageing. 3  Telomerase is also found in high levels in cancer cells.
1 Human cells cultured in the lab have been observed to stop dividing when telomerase is inactivated, because the length of telomeres is not maintained after cell division.  The cells then enter a state of inactivity called senescence. However, once telomerase is reactivated, the cells are able to continue dividing.