Is there any advanced filtering of date range expressions available in Eloqua Activity Bulk API?

Hello all,

We are looking for any advanced ways of filtering activity bulk API exports via definition criteria. From the online documentation, from what I can tell that we can create a new definition with filter criteria looking based on a specific date/time stamp, but not necessarily anything beyond that.

For example, the documentation shows the following:

"filter":"'{{Activity.Type}}' = 'EmailClickthrough' AND '{{Activity.CreatedAt}}' >= '2014-08-01' AND '{{Activity.CreatedAt}}' < '2014-09-01'"

We would be looking for something similar to:

'{{Activity.CreatedAt}}' >= NOW - INTERVAL 10 MINUTES

Or, similarly something that can give us X minutes worth of data since the last time the definition was synced against.

Any good ideas? Anything I'm missing from the documentation?