  We study the $1$-level density of low-lying zeros of quadratic Dirichlet
$L$-functions by applying the $L$-functions Ratios Conjecture. We observe a
transition in the main term as was predicted by the Katz-Sarnak heuristic as
well as in the lower order terms when the support of the Fourier transform of
the corresponding test function reaches the point $1$. Our results are
consistent with those obtained in previous work under GRH and are furthermore
analogous to results of Rudnick in the function field case.
