I immediately thought about ice crystals, but the article addresses that:
> Methods have been developed to quickly freeze organs for longer-term storage without risking damage from ice crystal formation, but ice crystals can also form during warming. To address this problem, Yadong Yin and colleagues advanced a technique known as nanowarming, pioneered by collaborator John Bischof, to employ magnetic nanoparticles and magnetic fields to thaw frozen tissues rapidly, evenly and safely.
> The second field realigned the nanoparticles, effectively tapping the brakes on heat production.
The heating slowed fastest in areas with more nanoparticles
Probably very stupid question, but can this be used also for cooling? Let the nanoparticles absorb some heat, then use a magnetic field to align them, then repeat?
There is no mechanism for cooling the magnetite particles below the ambient temperature.
A ferromagnetic material that is placed in an alternating magnetic field is heated by the so-called hysteresis losses, which happen when the material is magnetized, demagnetized and remagnetized. This can be seen e.g. in an electric transformer with a ferrite core, where the transformer core will become hot during operation (the iron cores used in low-frequency transformers are also heated by eddy currents, like an induction stove, but ferrites are insulators, so they are heated only by hysteresis losses).
Because the magnetite nanorods are anisotropic, the heat produced will depend on their orientation vs. the alternating magnetic field.
This is used to modify the heating rate, but there is no way to do cooling.
There exist magnetic refrigerators, which are based on the magnetocaloric effect, but they use very different magnetic materials, e.g. based on gadolinium or other rare-earth metals. Those are efficient only at extremely low temperatures, close to zero kelvin, so they would be useless for freezing animal tissues.
It isn't mentioned, but I would think that this works for cryonics... the ice crystals were one of the biggest sticking points. Well, aside from the original cause of death of course
I remember an arc in the Dick Tracy comic strip in the 1980s where the villain was a cryonics expert who had invented some quick way to thaw out corpsicles and thus revive arch criminals of the past.
Dick Tracy had the such over the top villains... nearing on superhero comic stuff, which it competed with. I don't think there was any multiverse arc, though.
I think the harder part is freezing fast enough. Experiments have been done with freezing and thawing small mammals. They survived but there was a maximum size after which they couldn’t be frozen solid pretty much instantly.
I would say more research needed, but it seems promising to me. After we get it working for transplant organs would probably be a better time to investigate this application.
Iron is less dangerous than most metals, but such excessive quantities in an insoluble crystal form, where the iron has to be reduced to become soluble, might create hard to predict problems.
So all those dreams of freezing your dead body for science to revive you later when it advances weren't that crazy after all. Or at least this might give a renewed source of customers with too much money to grifters promising eternal life.
Not being able to hit Pause on a medical issue will probably seem on par with doing healthcare without antibiotics. We simply happen to live in the years before that.
If you're trying to speed run immortality, it's probably best to avoid solutions to longevity that rely on your descendants not turning you into an amusement park ride.
Lots of dead people are going to wake up in horror simulators. Or as Tamagotchi.
This company makes organ transport boxes that circulate blood through the organs and control temperature. Many transplant center in the US are using it.
> Methods have been developed to quickly freeze organs for longer-term storage without risking damage from ice crystal formation, but ice crystals can also form during warming. To address this problem, Yadong Yin and colleagues advanced a technique known as nanowarming, pioneered by collaborator John Bischof, to employ magnetic nanoparticles and magnetic fields to thaw frozen tissues rapidly, evenly and safely.