Population genetics and Formicidae

Oh, ok. conduit to freeze the muscles. I remember I wasn't supposed to get the N2 on the floor, as it would eat the linoleum (which of course, I really wanted to do). Suppose it would do the same to tissue.
 
Roman said:
Oh, ok. conduit to freeze the muscles. I remember I wasn't supposed to get the N2 on the floor, as it would eat the linoleum (which of course, I really wanted to do). Suppose it would do the same to tissue.
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I think the effect is more due to the sudden cooling to very low temps forming crystals of intracellular fluid which on thawing lead to ice crystal damage.

Something like this:

http://www.blackwell-synergy.com/doi/abs/10.1111/j.1365-2621.1981.tb02998.x

edit: in case you can't access that:

When meat and poultry are frozen, the water that is a natural component of all meats turns to solid ice crystals. The water expands when it freezes. The sharp-edged crystals push into the surrounding tissue, rupturing the cells. The water that is outside the cell wall freezes first. As it does, it leeches water from inside the cell walls. When it thaws, the original balance does not return to normal. The thawed product will have lost some of its natural springiness. The water released during freezing seeps out of the thawing meats into the package.
 
Same reason why you never, ever rub frostbite.

Interestingly, you can take a small amount of water (like a droplet) and get it below freezing wihtout it crystallizing, as long as it remains undisturbed. This helps bugs last the winter. Crawl under some bark, dehydrate their tissues a little, and produce some antifreeze. Then hope a woodpecker doesn't get you.
 
Roman said:
Same reason why you never, ever rub frostbite.

Interestingly, you can take a small amount of water (like a droplet) and get it below freezing wihtout it crystallizing, as long as it remains undisturbed. This helps bugs last the winter. Crawl under some bark, dehydrate their tissues a little, and produce some antifreeze. Then hope a woodpecker doesn't get you.
Click to expand...

You know the strangest things.:p

Is that the same as supercooled water?
 
I'm presently trying to figure out how to use 10 ul of cDNA for triplicates for RT-PCR to test mRNA expression for 5 enzymes.

Any suggestions? The 10 ul is stock cDNA.
 
You're turning DNA into its mRNA component to test for whether it expresses for certain enzymes?

I do population genetic work, which looks at ITS and microsats. And sex chromosomes. Heh heh. Sex reactions.

Sorry, though, I really can't be of much help. I've not even done a full year of undergraduated bio work. I imagine the dilution of that 10 ul would be fairly important. x ng /ul.
 
Roman said:
You're turning DNA into its mRNA component to test for whether it expresses for certain enzymes?

I do population genetic work, which looks at ITS and microsats. And sex chromosomes. Heh heh. Sex reactions.

Sorry, though, I really can't be of much help. I've not even done a full year of undergraduated bio work. I imagine the dilution of that 10 ul would be fairly important. x ng /ul.
Click to expand...

Yeah, but I don't want the Ct's to extend ad infinitum.

Oh well back to the drawing board.
 
Oh... limit the number of cycles, then?

If you know the dilution and size of the molecule, then you can work out how many strands you have. Following that, it's a simple exponential progression each time you cycle it.

Though there's probably some super high tech way where you engineer a molecule that degrades in so many replications.

Good luck, all the same.
 
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