  We revisit the analysis of the drag a massive quark experiences and the wake
it creates at a temperature T while moving through a plasma using a gravity
dual that captures the renormalisation group runnings in the dual gauge theory.
Our gravity dual has a black hole and seven branes embedded via Ouyang
embedding, but the geometry is a deformation of the usual conifold metric. In
particular the gravity dual has squashed two spheres, and a small resolution at
the IR. Using this background we show that the drag of a massive quark receives
corrections that are proportional to powers of log T when compared with the
drag computed using AdS/QCD correspondence. We use the perturbation produced by
the quark strings to compute the wake and compare with the results obtained
using AdS/QCD correspondence. We also study the shear viscosity with running
couplings, analyze the viscosity to entropy ratio and compare the result with
the known bound. In the presence of higher order curvature square corrections
from the back-reactions of the embedded D7 branes, we argue the possibility of
the entropy to viscosity bound being violated. Finally, we show that our set-up
could in-principle allow us to study a family of gauge theories at the boundary
by cutting off the dual geometry respectively at various points in the radial
direction. All these gauge theories can have well defined UV completions, and
more interestingly, we demonstrate that any thermodynamical quantities derived
from these theories would be completely independent of the cut-off scale and
only depend on the temperature at which we define these theories. Such a result
would justify the holographic renormalisabilities of these theories which we,
in turn, also demonstrate. We give physical interpretations of these results
and compare them with more realistic scenarios.
