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\section{The simulation}  We simulated a 10pc periodic cube of a molecular cloud, beginning from fully developed isothermal  turbulent initial conditions. We generated the turbulent initial conditions using version 4.2 of the ATHENA code \citep{2005JCoPh.205..509G,2008JCoPh.227.4123G,2008ApJS..178..137S,2009NewA...14..139S}. The turbulent driving was technically similar to that of \citet{2009ApJ...691.1092L}. Briefly, on a $1024^{3}$ grid with domain length 1 we applied divergence-free velocity perturbations at every timestep to an initially uniform medium. The perturbations had a Gaussian random distribution with a Fourier power spectrum $\left | d {\bf v}_{k}^{2} \right | \propto k^{-2}$, for wavenumbers $2 < k/2 \pi < 4$. Similarly to, e.g., \citet{Federrath_2013}, turbulence on smaller length scales was generated self-consistently from the large scale driving. The driving continued until the box reached a saturated state at a Mach number $\mathcal{M}$ of roughly 8. During this driving stage we did not include gravitational forces.  At this point we scaled the box to a physical size $S = 10$ pc, mean number density $n = 100$ cm$^{-3}$ at mean molecular weight $\mu=2.33$, and a constant sound speed $c_s$ = 0.2 km s$^{-1}$. After turning off the forcing and turning on self gravity, we turned the simulation over the adaptive mesh refinement (AMR) code RAMSES \citep{2002A&A...385..337T}. The $1024^{3}$ base grid was maintained, along with 2 steps of adaptive refinement triggered when the local Jeans length became shorter than 4 grid cells \citep{1997ApJ...489L.179T}.   We integrated the box through $\sim1.25$ Myr of self gravitation gravitating  evolution. Following \citet{2007ApJ...665..416K}'s definition of the turbulent turnover time in a box , $T_{turb} = S/(2 c_s \mathcal{M})$, we have $T_{turb} \sim 3$ Myr. The free-fall time $T_{ff} = [3\pi / (32 G \rho)]^{1/2}$, at the mean density of the simulation, is also roughly 3 Myr. In this paper we focus on moderately dense gas, with $10^3 < n/{\rm cm}^{-3} < 10^{4.5}$; at these densities we have $0.2 \lesssim T_{ff} / \rm{Myr} \lesssim 1.0$. At 1.25 Myr the global structure of the simulated box is thus dominated by the turbulence, while the denser gas has had time to become organized by self gravity.