Changes and additions from ASTRAL 1.73 to 1.75:

* SPACI and AEROSPACI scores

We re-calculated AEROSPACI and SPACI scores for all PDB files in
ASTRAL 1.75, including entries that were present in older versions.
New scores were calculated using version 7.0 of WHAT_CHECK
(http://swift.cmbi.kun.nl/gv/whatcheck/), which gives slightly
different results than the version we were previously using.


* ASTEROIDS

Pfam release 23 was used to create ASTEROIDS in ASTRAL 1.75;
these were first released on October 1, 2009.

We created ASTEROIDS using all protein chains from PDB entries that
are not classified in SCOP 1.75.  This includes entries released
before the SCOP freeze date that were not classified in SCOP, as well
as entries released after the freeze date.  Nucleic acid chains, and
additional chains from PDB entries that are classified in SCOP, are
not included in ASTEROIDS.