Tubing and odors, a non-ideal combination

In olfactometry, one is constantly fighting to produce temporally precise and stable concentration outputs.  This is especially critical when you want to make detailed measurements of perception or neural activity.  Unfortunately, investigators are constantly confounded by artifacts that can distort the temporal properties and concentration profile of odor output.  On this blog, I hope to eventually cover several issues that typically come up in calibrating olfactometers.  In this first installment, I will deal with the issue of tubing after the jump.