sanger/sequencescape — pull request #629 by mattdenner (2012-09-25 11:49:27+00:00)
Title: [#36231943] Use an exclusive scope in record lookup

It's important to always use a blank scope on the model when retrieving
them by ID in the AmqpObserver. Without the exclusive scope we get odd
behaviour, particular in sample accessioning where a named_scope is then
combined with find_each.