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.
Telomeres delay ageing of the cell. Scientists now began to investigate what roles the telomere might play in the cell. Szostak's group identified yeast cells with mutations that led to a gradual shortening of the telomeres. Such cells grew poorly and eventually stopped dividing.