A substance at $4^{\circ}C$ has a thermal expansion coefficient $\beta = \dfrac{1}{v}\left ( \dfrac{\partial v}{\partial T} \right )_P =0 \:K^{-1}$, an isothermal compressibility, $k_{T} =- \dfrac{1}{v}\left ( \dfrac{\partial v}{\partial P} \right )_{T} = 5 \times 10^{-4} Pa^{-1}$ and a molar volume $v = 18 \times 10^{-6}\:m^{3}\:\text{mol}^{-1}$. If $s$ is the molar entropy, then at $4^{\circ}C$, the quantity $\left [ v\left ( \dfrac{\partial s}{\partial v} \right )_{T} \right ]$ evaluated for the substance is ________________ $J \:\text{mol}^{-1}\:K^{-1}$ (rounded off to the nearest integer).