I’ve been having a similar issue in a couple different contexts. My periods of growth in between dilution events are not very exponential. They seem kind of… sigmoidal? (img below)
Any one have ideas/experience/solutions for this?
My hypotheses/experiments to try listed here:
- Is it a simple calibration issue? Recalibrate to test.
- Is it a true biological effect, where they saturate at relatively low density? The most likely candidate for such a limiting resource is oxygen, so maybe try different stir rate and see if it goes away? (currently stirring at “8”, do people routinely do higher?)
- Is it that I’m looking at or thinking about this incorrectly? Perhaps i shouldn’t expect to see a exponential-like curve at these scales. I’m just hoping to get my data looking as best I can for calculating growth rates later on.