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Re: [Phys-l] Bacteria problem



Hi all-
I don't see why this isn't a straigtforward case of Poisson statistics.
Regards,
Jack


On Fri, 4 Jan 2008, Bernard Cleyet wrote:

, which explains chem. reaction rates increasing so much w/ only a sl.
increase in temp.

bc hopes that wasn't impulsive.

Brian Whatcott wrote:

At 10:55 AM 1/4/2008, Savinainen Antti, you wrote:


Hi again!


"When modelling bacterial growth, it is often assumed that the
bacteria have a certain "division time" (the time in which a single
bacterial cell divides into two) that is constant, let's say 20
minutes. As it can be easily shown,this leads to an exponential
increase in the number of bacteria. However, the "division time"
is definitely not constant in real life. What happens if
we assume that the "division time" is normally distributed with
a given mean and standard deviation, let's say with a mean of
20 minutes and a standard deviation of 5 minutes?
What kind of model would describe this situation, if
we also assume that the initial amount of bacterial cells is
quite small, let's say 2?"

Cheers!

Antti




A point dwelt on by "Limits to Growth" advocates, is that constant rate growth
of any positive value ends up in the stratosphere.
A variable doubling time amounts to a variable growth rate in unit time.
Here you model an assemblage of variable rate entities which also
hit the stratosphere a little sooner than growth at the mean rate,
thanks to the fast end of the distribution........



Brian Whatcott Altus OK Eureka!

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_______________________________________________
Forum for Physics Educators
Phys-l@carnot.physics.buffalo.edu
https://carnot.physics.buffalo.edu/mailman/listinfo/phys-l


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