Minimum light for photocytes

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wapcaplet
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Minimum light for photocytes

Post by wapcaplet » Tue Jan 03, 2017 10:29 pm

Some comments in this thread about photocytes, and my own experiences with photocytes gone crazy, have got me thinking about ways to prevent photocytes from being such an unlimited free energy source. So I've done some experiments, taken notes, and would like to share my results :-)

First, some comments on methodology: My objective was to figure out the lowest amount of light where a photocyte is still "viable" (meaning it can keep splitting indefinitely, instead of dying out after only a few splits). Photocyte viability depends on at least three factors: Light amount, salinity, and cell split mass.

I set up a basic substrate with maximum light range, so it would be uniformly lit, and created a genome with an M1 photocyte that splits into two more M1s. For a given salinity (say, 0.2), I would guess a light level, place 1 cell, and see how it splits. If it dies, increase light. If it thrives, decrease light. Repeat until I find the (approximate) amount of light where M1 is just barely getting enough light to survive. In many cases, this leads to very slow growth--around 100 hours per split, in some cases.

Then I repeated the process again for each salinity level (in increments of 0.2) and cell split mass (using default snap values). It's tricky to get exact values with the sliders; I used landscape mode to get as much accuracy as possible, but these results are only approximate. A few times, I would see 4 or 5 splits, then most of the cells would die, but a few would survive and continue splitting; these must be right on the razor's edge of survivability.

Here's the chart and numbers:
photocyte-minimum-light.png
To nobody's surprise, higher salinity corresponds to less light required for viability. What did surprise me was how much of a difference there is between 1.40ng and 1.53ng, and how little difference there is above 1.53ng. Larger split mass should mean more cell surface area, thus more available light used, but I did not expect such a huge discrepancy. I also found it surprising just how little light is needed for the higher split masses--some of them are indistinguishable from 0 if you're just looking at the slider.

I did some cursory tests with connecting photocytes to other cells (say, a flagello-photo swimmer, or a photo/lipo pair) under these minimal light conditions. Using the minimum light for cell survivability, there is really no energy to spare--a flagello-swimmer with a photocyte head quickly uses up its nutrients and dies; in a photo/lipo pair, the photocyte dies unless it has a much higher nutrient priority than the lipo. This seems worth researching further.

I'm pleased that I got photocyte growth slowed down to where it's more like watching grass grow, instead of always being an instant population explosion. Obviously there are other ways to do this (such as a rotating light with limited range), but I think I achieved my goal of "nerfing" photocytes, and proved that it's possible to make a substrate where photocytes can be allowed without it leading to instant cheat-mode. :twisted:
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bwisialo
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Re: Minimum light for photocytes

Post by bwisialo » Wed Jan 04, 2017 12:42 am

Charts! :D
amor fati
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Nayus
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Re: Minimum light for photocytes

Post by Nayus » Wed Jan 04, 2017 3:44 pm

Cool discovery!

How did you make that awesome-looking charts? :) :o

I'm doing some experiments on my own and this level of graphs would be great!
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bwisialo
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Re: Minimum light for photocytes

Post by bwisialo » Wed Jan 04, 2017 4:30 pm

Basically, you van enter that chart of numbers into, eg, Excel, and then select chart options. The work is in getting the numbers.
amor fati
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Nayus
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Re: Minimum light for photocytes

Post by Nayus » Wed Jan 04, 2017 4:50 pm

Yes, but I want to know which specific program was used.. I used an online grapher and I got this result that... isn't that bad but the one above here is better

Image
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bwisialo
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Re: Minimum light for photocytes

Post by bwisialo » Wed Jan 04, 2017 6:08 pm

Y = Salinity, and you need one plotline for each weight. Is that what you tried to do there? Excel with handle this data just fine fine and give the desired geaphs.
amor fati
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wapcaplet
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Re: Minimum light for photocytes

Post by wapcaplet » Wed Jan 04, 2017 7:43 pm

I used Google Sheets, but you could do the same with Excel, LibreOffice etc.
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