If you've pulled the development branch of Tripal from git within the
last 12 hours you may now received some errors on your site with an
error occurring at line 1991 of tripal_core.api.inc. I had to change
the way the persistent database connection was stored. So, if this
message persists after clearing cache, etc., you can run this query to
clean things up:
DELETE FROM variable WHERE name = 'tripal_persistent_chado'