Frozen human brain tissue works perfectly when thawed 18 months later - eviltoast
  • Possibly linux@lemmy.zip
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    6 months ago

    The problem is that it wouldn’t scale. You can freeze a rat but you can’t freeze a human. Humans have to much mass to freeze quickly enough

    • CanadaPlus@lemmy.sdf.org
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      6 months ago

      A lot of people don’t realise, we can and did. In the 50’s. It completely works on small creatures.

      Unfortunately, like you said, cooling is really hard to do quickly in bulk, and no cute tricks have been forthcoming quite yet.

      • Possibly linux@lemmy.zip
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        6 months ago

        It is a matter if physics. Humans have to much mass. You might successfully freeze the outside but the organs will be destroyed by ice crystals. There also is the issue of if we should but that is a discussion to another day.

        • CanadaPlus@lemmy.sdf.org
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          6 months ago

          The most obvious way around that would be some kind of cryoprotectant, but those have all proven very toxic so far. The next frontier would be trihalose, which we’ve figured out how to produce in quantity recently, so watch out for news on that. To get something hot evenly and quickly, RF heating works great, but it’s not obvious there’s any equivalent for cooling, unless you’re dealing with a few already-cryogenic atoms. One thing I’ve wondered about is using high pressures that depress the freezing point of water, but those kinds of pressures are sometimes biochemically toxic on their own. No research on short exposure in animals seems to exists, unfortunately.

          It’s so close to working, I feel like we’ll solve it eventually, but I don’t know when or how.

          • Possibly linux@lemmy.zip
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            6 months ago

            If I remember correctly the issue has to do with the water in your bodies you can only cool water so fast. If I am recalling correctly you couldn’t even do it with absolute zero temperatures as the water takes to much time to lose energy.

            • CanadaPlus@lemmy.sdf.org
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              6 months ago

              Well, no. Reductionism still holds. If you could magically make the water everywhere inside super cold, it would behave locally just like water in a smaller creature. Unfortunately, it seems impossible to do that. Even pumping coolant through the circulatory system, which is a thing I know at least happens in some related procedures.

              • Possibly linux@lemmy.zip
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                6 months ago

                Its a very complex problem. Even if you pump coolant it will either prevent cells from getting oxygen or clog both of which are bad.

                My point previously was that water doesn’t conduct heat well. (0.6065 W/(m·K))

                • CanadaPlus@lemmy.sdf.org
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                  6 months ago

                  Yeah, it’s a doozy of an engineering problem. It’s like trying to build a lever out of sand. There’s just no way to tackle it straight.