(resummation) effects in $\nu
W_2$ should be possible. Recall, that as a two-scale process BFKL dynamics does not directly govern the small-x behavior of $\nu W_2.$ However, BFKL effects are certainly present and can be systematically included through resummations such as the one indicated in (6.2). When the next-to-leading corrections are known we should begin to get a reliable indication of the importance of these resummation effects in the HERA regime. (ii) The next-to-leading resummations should help us to better understand where the operator expansion is valid in small-x physics, that is at what  $x$  and $Q^2$ are coefficient and anomalous dimension functions sufficiently safe from diffusion effects to be reliably calculated perturbatively\[47,48\].

Nuclear reactions
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Nuclear shadowing in deep inelastic scattering
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Nuclear shadowing in deep inelastic scattering is known to be a leading twist phenomenon\[29\] and thus dominated by soft physics, at least at current x-values. In the DGLAP formalism shadowing effects are put into initial parton distributions. However, when shadowing is not too strong it can be calculated from diffractive deep inelastic scattering using the Gribov-Glauber formalism as illustrated in Fig.10. In that figure the left-hand part represents the imaginary part of the forward $\gamma^*$-scattering amplitude which, 