The activation energy of one of the reactions in a biochemical process is \( 532611 \, \mathrm{J \, mol^{-1}} \). When the temperature falls from \( 310 \, \mathrm{K} \) to \( 300 \, \mathrm{K} \), the change in rate constant observed is \( k_{300} = x \times 10^{-3} k_{310} \). The value of \( x \) is ____________
[Given: \( \ln 10 = 2.3 \)
\( R = 8.3 \, \mathrm{J \, K^{-1} \, mol^{-1}} \) ]