4 ms·
Not sure where his 500k years figure comes from. A cursory search gives 521 years: https://www.nature.com/news/dna-has-a-521-year-half-life-1.11555 https://www
by gnramires 7y ago
Not sure where his 500k years figure comes from. A cursory search gives 521 years:
https://www.nature.com/news/dna-has-a-521-year-half-life-1.11555 https://www.nature.com/news/dna-has-a-521-year-half-life-1.1...
Chemical decay tends to follow Arrhenius equation:
https://en.wikipedia.org/wiki/Arrhenius_equation#Equation https://en.wikipedia.org/wiki/Arrhenius_equation#Equation
so indeed a difference of maybe 40C should lead to a difference in half life of about 20-30%. I think about 30 half lives (~10^-9 degradation factor) should be the limit of recoverability, so perhaps 521x30 = 15k years in normal conditions up to 521x30x1.25 = 20k years in low temperature.
Of course, other factors such as humidity could contribute as well to the half-life, and reactivity is a lot more complicated than the Arrhenius model in reality. But even then I would be surprised such a vast difference in reactivity outside of true cryogenic conditions (maybe even shielding from radiation?).
edit: your second edit is interesting :) is that curve polynomial or exponential?
- Robotbeat 7y agoLooks exponential to me. After all, the Arrhenius equation (whose constants seem different here than your earlier assumptions) is exponential.
- gnramires 7y agoOh yes, I definitely messed up my calculations. Half life is (inversely) proportional to the reaction rate itself I guess (I were associating it with the exponent, because half life is usually in the exponent), so the half life itself would be proportional to exponential reciprocal of temperature (e^(a/T)). This means significant differences in HL for minor temperature variations under e.g. Arrhenius model (consistent with your graph I think). To extrapolate it some parameters need to be estimated though, which sounds interesting, I'll get around to that later...