Gav
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Yeah, sorry, I felt bad for not acknowledging that bit.
I guess that sufficiently long patient storage at dry ice temperatures would just result in a super thin (nanoscale) layer of ice forming on basically all the nucleation-inducing surfaces (which could then all potentially grow with rewarming), right?
Hmm.. that's a really good question. Off the top of my head I don't know where the actual amount of ice growth over time can be figured out. I'll keep an eye out for more info.
Trouble is, I think, that (depending on perfusion) at -80'C it's water is well below even a suppressed 'freezing point', but still well above the glass transition temp(approx... (read more)
Also just another thing that might be interesting:
Check out 'intermediate temperature storage', the idea of storing at a slightly warmer than liquid nitrogen temps (-130'C as opposed to -196'C) is a good idea in order to avoid any fracturing*. This is right near the glass transition temp, so no nucleation can proceed.
Tricky part is there aren't any practical scalable chemicals that have a handy phase change near -130'C, (in the same way that liquid nitrogen does at -196'C) so any system to keep patients there would have to be engineered as a custom electrically controlled device, rather than a simple vat of liquid.
Not impossible, but adds a lot of compexity. They might end up doing it in a few years by putting a dewar in a dewar, and making a robust heater that will failsafe down to LN2 if there's any problem.
*Personally I'm not concerned with fracturing, it seems like a very information-preserving change compared to everything else.
I'm stuck at work for a while, so this is going to be painfully short, sorry.
The bit you're missing is getting below the glass transition temperature prevents both heterogeneous and homogenous nucleation. Dry ice is still well above the glass transition temperature.
Quickest online result I could find for the relevant graph is here: http://www.benbest.com/cryonics/vitrify.html, in section III. Axis labels are "Cryoprotectant concentration" and "Temperature (*C)"
(Although there's a nicer graph Fig3, p36 in Wolker's "Cryopreservation and Freeze Drying Protocols", which just came out this month. Probably not online as of yet)
At very high cryoprotectant concentration (right hand side of the graph) you can transition from 0C to below the... (read more)
Hmm.. wait a tic. Helmets absorb shock if your head hits something. On the motorcycle that's pretty much anything around me. But in the car, what exactly can my head hit?
I drive a recent model vehicle, and there's at least two* airbags around the driver. I can't think of any unprotected objects that my head could strike, that a helmet would help deal with. Plus if I wear a helmet, the added mass my neck supports is going to make it more likely to suffer whiplash, surely?
Not to mention that helmets seem to be designed to stop large accelerations over very short distances (i.e. soft-ish foam a couple of cm... (read more)
Dang it, days later and I'm still insanely curious to see how the results would differ if the length of the matches wasn't known by the algorithms. Either by removing the concept of limiting matches, or by ending matches far earlier(not just one or two steps) than they were 'planned' to end.
I've been pondering downloading the code, changing and running it, but my shoulder angels start slapping me at the thought of me neglecting my current projects to (even briefly) learn Haskell.
Just occurred to me that there's a way around this, I can offer a shameless bribe to someone else that already knows what they're doing and has some spare time. :-D
With that in mind, $20USD via paypal to the first person who runs the modified tournament and posts the results as a reply to this comment. If you don't want the cash, I'll donate it to MIRI/a charity of your choice, etc.
I'm kinda surprised, my naive intuition was that SimHatingTitForTat would force a cooperative win.
Does anyone know if the lack of SimHatingTitForTat getting into the finals is an artifact of the algorithms knowing the length of the rounds? (I.e. they can decide to backstab on the final turn to get an extra point).
Tongue in cheek thought that just popped into my head: There is no great filter, and we are actually seeing intelligence everywhere because it turns out dark matter is just a really advanced form of computronium.
I have to +1 'Writing essays'.
Too easily overlooked in a technical environment, but it really pays off. Both to assist in consolidating your own ideas, and also in communicating them to others.
Linux/Unix & their associated command line stuff. The number of times it's come in handy to be able to SSH into a machine that's way over there and do stuff is immense. Sadly I waited till Uni to learn, and I wonder where I'd be now if I'd internalised these concepts by the age of 15.
Need to log something you've just done? Redirect the output into a file. Boom. No longer do you have to find the bit of software that does everything, you just need programs that do simple stuff you can repurpose*.
Reading FOLDOC a bit to get the history was handy too. Thinking of computers as CPUs attached... (read more)
OK, here's the gossip: (again, I'm not a scientist, but I'm pretty sure nothing here is grossly misleading).
Some background: M22 is the formula used by Alcor, and VM-1 is the solution used by Cryonics Institute. Both are designed by professional cryobiologists, and M22 is patented (as well as being extensively used for cryoprotection of tissues in 'regular' labs).
There's some info here: http://www.evidencebasedcryonics.org/2008/07/08/vitrification-agents-in-cryonics-m22/ VM1 is extremely stable against ice formation at dry ice temps of -80
C. However it's more toxic, and wasn't designed for anything other than cooling down. M22 is less stable at -80C, however it's been incredibly cleverly formulated to minimize toxicity, and increase perfusion. It's also got features (such... (read more)