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Respirometry without scrubbing CO2 and water vapor
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If you are unfamiliar with the fundamentals of respirometry, you might want to read this page before diving into the rest of this section..   Also, John Lighton's book, Measuring Metabolic Rates - A Manual for Scientists is an excellent reference.
After selecting the No-Scrub option from the Toolbar or the Respirometry menu, this window appears:
You need to select the channels for O2 deflection (∆ O2), CO2, and water vapor pressure. The next window is for selecting the channel with flow rate data (or use of a constant flow rate), along with STP data:
Next, you need to indicate the arrangement of the respirometry system 'plumbing':
Note that since CO2 and water vapor are not scrubbed from the analyzed gas, the arrangement of the sensors for O2, CO2, and water vapor is not important (and either the O2 or CO2 sensors are not necessary if those data are estimated from RQ). Similarly, it is irrelevant if the flow through the gas sensors is subsampled. What IS important is the position of the flowmeter with respect to the animal chamber (or mask): upstream versus downstream.
Finally, you need to select which of the three computed gas exchange rates are to be saved. Note that these variables are always stored in NEW channels, so you must have less than 38 existing channels if you wish to save all of them. You must select at least one channel to save.
The default output units for these channels are ml/min for VO2 and VCO2, and mg/min for mH2O. You can use the pop-up buttons to output results in a variety of other units. If you select heat-related units (e.g., watts, kilojoules/day, etc.), you will need to specify either the heat equivalent of VO2 and VCO2 or (for evaporative water loss), the temperature of the evaporating surface. The latter has a small effect on the heat of evaporation.
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