  Using three years of the Journal Citation Reports (2011, 2012, and 2013),
indicators of transitions in 2012 (between 2011 and 2013) are studied using
methodologies based on entropy statistics. Changes can be indicated at the
level of journals using the margin totals of entropy production along the row
or column vectors, but also at the level of links among journals by importing
the transition matrices into network analysis and visualization programs (and
using community-finding algorithms). Seventy-four journals are flagged in terms
of discontinuous changes in their citations; but 3,114 journals are involved in
"hot" links. Most of these links are embedded in a main component; 78 clusters
(containing 172 journals) are flagged as potential "hot spots" emerging at the
network level. An additional finding is that PLoS ONE introduced a new
communication dynamics into the database. The limitations of the methodology
are elaborated using an example. The results of the study indicate where
developments in the citation dynamics can be considered as significantly
unexpected. This can be used as heuristic information; but what a "hot spot" in
terms of the entropy statistics of aggregated citation relations means
substantively can be expected to vary from case to case.
