Impact of loop statistics on the thermodynamics of RNA folding
  Loops are abundant in native RNA structures and proliferate close to the unfolding transition. By including a statistical weight ~ l^{-c} for loops of length l in the recursion relation for the partition function, we show that the calculated heat capacity depends sensitively on the presence and value of the exponent c, even of short t-RNA. For homo-RNA we analytically calculate the critical temperature and critical exponents which exhibit a non-universal dependence on c. 
Thomas R. Einert (1), Paul N\"ager (1), Henri Orland (2), Roland R.   Netz (1) ((1) Physik Department, Technische Universit\...