Figure 2.

Design, implementation and reaction time of the olfactometer. (A) Schematic showing the “standby” condition of the olfactometer. Diagram for the two-odor delivery unit was shown. The flow meter was designed for monitoring potential system failure. The flow rate was labeled as the numbers with the unit “L/min”. Arrows indicated for the direction of air flow. (B) Schematic showing the “working” condition when one odor was delivered (through “r2”). Reduction of the readout from the flow meter indicated for normal operation. (C) Photo of the flow-controlling unit for the olfactometer. (D) Photo of the tubing unit and mixing chamber. Thin tubes were used for fast reaction for odor delivery. Mixing chamber was designed for a maximal mixture of pure air (from “r1” in B) and the delivered odor (from “r2” in B). (E) Fast response of the olfactometer. Readout from photoionization detector (PID) was plotted in the log scale for main figure and linear scale for inset (Mean ± SEM, standard error of the 0mean, unless stated otherwise; calculated from odor application of 200 trials). Rising/decay time constant and time with residual-odor were shown in Table 1. (F) Odor stability across trials.