CA induced differentiation

The present experiment is a continuation of the previous one. Now the proliferon consists of three processes. The set points of CA-2 and CA-3 are respectively >= 20, >=23. In addition a declining set point which is triggered by  CA-1 daily production, determines the frequency of resource delivery from CA-3 to CA-2. CA-2 is depicted in the previous experiment.

As the CA-1 set point declines CA-2 loses more and more cells and gradually assumes the CA-2 solution. At set point = 8 the proliferon consists of two equal transitory processes.

The last image illustrates the mechanism behind the CA-3 structure change. As the CA-1 set point declines CA-3 is triggered more often to deliver resources to CA-2.  The resources of some cells are depleted, they die and  CA-3 structure changes. The outcome depends on two rates. Resource accumulation (RA) and depletion (RD). The isolated CA (s.p. 25) merely accumulates resources and its structure does not change.  At lower set points RD becomes more pronounced and for short periods CA-3 structure changes. As the set point declines it triggers more and more resource deliveries from CA-3 to CA-2 and the change in its structure becomes more pronounced. CA-2 structure does not change since it accumulates resources.

CA-1 triggers differentiation

The stem process (CA-1) is isolated and does not deliver resources. It only triggers transitory processes (CA-2, CA-3) to do so. Initially CA-3 is undifferentiated. As the set point declines, CA-3 becomes more and more similar to CA-2. In other words it differentiates to the CA-2 state. The declining CA-1 set point brings about CA-3 differentiation. Despite their similarity CA-3 has less resources than CA-2.

Passage through the solution space

Initially the proliferon solution consists of an oscillating  CA-2 and an isolated CA-3. Then CA-1 triggers a differentiation which promotes the proliferon to a new solution (attractor) in which both transient processes have the same structure. Thus the entire proliferon differentiates from one solution to another.

Tolerance to change

Resources of a process determine its resistance or tolerance to change.  CA-1 triggering was initiated at the beginning of the experiment. However, if the experiment would have started after CA-3 had accumulated more resources RA >> RD, and CA-3 would not have differentiated.

nca=3; restoreparams[1,1,1]; restoreparams[2,1,1]; restoreparams[3,1,1]; If[sa[[2]] >=23 ,donate[3, 2]]; If[ sa[[3]] > sa[[2]] && sa[[2]] >= 20 && sa[[1]] >=k, donate[3, 2]]; {k,, 23, 2, -1}; If[nowdat[[no,8]] <= 2, newzygote[no]];

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