More on anti-cryonics writing

Further to my last blog post, A survey of anti-cryonics writing :

  • I copied the article to LessWrong.com after being encouraged to do so by users there who also gave me some great help improving the writing. It had 215 comments last I looked.
  • I received email from Ralph Merkle:
    I asked David Pegg to review an early copy of “The Technical Feasibility of Cryonics.” My exchange with him was published in Cryonics magazine in the July/August 1993 issue starting on page 22. I believe you will find it interesting.

    My response to Shermer’s story in Scientific American is on the web.

    And, of course, my thanks for your efforts to seek clarification from “critics” of their actual technical criticism (if any).

    I haven’t had trouble commenting, so any help anyone can provide reproducing and diagnosing these problems gratefully received.
  • I missed a couple of anti-cryonics articles in my survey:
  • I found this article in which John Bischof speaks out against cryonics, so I mailed him, and he very politely replied almost immediately to say that cryobiologists consider cryonics a “faith based approach”, and pointed me at the Society for Cryobiology home page. Pressed for more detail, he replied:
    I think the distinction is between a tissue being dead vs. alive at the time of freezing. I don’t believe there is anything I can possibly write that would further clarify that distinction.
    I’ve yet to reply to this email; I may write a more general open letter to cryonics critics and send him a link. As always, I’m grateful for the time taken to reply.
  • Updated 2010-02-16: I found this Detroit News article in which Society for Cryobiology President John K Critser voices a negative opinion. Email sent 2010-02-11, no reply so far.
  • Updated 2010-02-20: Have now emailed again everyone I emailed last time drawing their attention to these articles. Really hoping that some of what I’ve written here spurs one of them into writing a more detailed attack on some aspect of cryonics.
  • Updated 2010-02-20: Got a reply from Stephen Barrett MD of QuackWatch: “Sorry, I am not interested in further involvement in your project. ”

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25.07.2010 13:58 Paul Crowley's Blog - A survey of anti-cryonics writing @blog.ciphergoth.org
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14.02.2010 12:25 Paul Crowley's Blog - A plea to critics of cryonics @blog.ciphergoth.org
iting and More on anti-cryonics writing for details). Strikingly, even when the Society for Cryobiology passed their 1982 by-law barring cryonicists from membership, they produced no detail to back up their claim that “it is the Board’s scientific judgement that the prospects for re-animation of a frozen h

Comments

10.02.2010 19:12 CP

Hm…I don’t think I repeat the “ice crystals” error, though I appreciate that my use of the term “frozen” might have given that impression, and I’ve made a note of that for future posts.

My main focus in “Corpsicles,” in any case, was that cryonics advocates tend to gloss over the difficulty of reviving a body that has died (by whatever definition), preserved/vitrified/frozen, and restored/de-vitrified/thawed. That’s a major technical hurdle; pointing out that defibrillators helped us change the definition of death doesn’t really point the way toward a solution to this much more challenging problem: Even assuming a complete absence of preservation or restoration-related damage, one is still confronted with a cadaver that must be revivified. That was the point I was making, or trying to make, in my post.

On the subject of damage related to preservation and thawing:

I understand that freezing is not the same as vitrification, and that vitrification is postulated as a solution to freeze-related damage, but my concerns are based on the fact that there’s been very little technical validation of this concept.

Simply describing how vitrification is supposed to overcome various kinds of damage isn’t the same as demonstrating that it could work. Much of the “support” for these claims comes from studies of conventional freezing of biological samples that are far smaller than a tissue or organ (e.g., worms or cultured cells), and the per-cell survival rates are not impressive. It’s also worth mentioning, per my point about the challenges of revival, that successful recovery of frozen samples has historically involved cells that were alive at the time of freezing.

As for specific studies of vitrification: The rabbit kidney papers from 21st Century Medicine, which are sometimes cited as the best experimental evidence in support of vitrification at the organ level, are (scientifically speaking) a total nightmare: anecdotal, poorly controlled, reliant on tiny sample sizes, and focusing way too much attention on rare positive results.

The data presented make it impossible to determine whether that survival was significant. One animal might have lived some number of days following a vitrify-and-transplant paradigm, but several animals did not; advocates tend to focus on the rare success rather than the more common failures.

Furthermore, the surviving animals received a lot of external support to assist with consequences of diminished kidney function. But what is the survival rate for a rabbit with no kidney at all that’s receiving treatment for hyperkalemia, anemia, and other consequences of loss of renal function? An important control, missing so far as I can tell. A proper study would require significantly larger sample sizes and more careful controls.

On another note, it would be nice to see a study from a group that doesn’t have a proprietary stake in the result. People with a profit motive have been known to misinterpret or misrepresent data — I’m not suggesting misconduct, of course, just pointing out that it’s very difficult to believe in a result when the only support comes from someone who might commercially benefit from the outcome.

The hippocampal slice data are somewhat more promising, but (a) these are very thin samples, and (b) the evidence of successful recovery focused intensely on histological detail rather than function. Also, again, the samples were fully metabolically active at the time of preservation.

There’s always another paper out there that one hasn’t read, and I’m slowly working through the literature, but at the moment I’m not far from where I started:

Vitrification is a word advocates invoke to avoid the criticism that freezing causes damage, but thus far there’s very little empirical support that it constitutes a real, practical technology capable of preventing preservation-related damage to organs and tissues in the real world. Extraordinary claims require extraordinary evidence, and so far that evidence is lacking.

10.02.2010 20:07 Paul Crowley

First off, many thanks for taking the time to write such a detailed response! You are right, you don’t repeat that specific error, and apologies if I gave the impression that you did; I had something else in mind that I’ll come to later.

I don’t think it’s fair to say that cryonics advocates gloss over the revival problem; only today I received in email a link to this article by Ralph Merkle that addresses it in detail. It’s just that if you believe that those in cryopreservation are not information-theoretically dead, it seems a bit hard to swallow that even with a thousand years of techological progress, no means to fix the damage could be found. In particular, the error I was referring to is that you don’t address at all the possibility of revival through scanning and whole-brain emulation. This seems to me to provide the most hopeful route: Whole Brain Emulation: a roadmap seems to me to give reason to be quite optimistic on this front.

I would certainly be happier to see more and better research in this area. I agree that the motivations of researchers can make a real difference to published outcomes even when there is no foul play, and it would be great to see critics doing work in this area to give us more information. However, it’s enough I think to move us out of “clearly wacked” territory, and into the territory where critics are going to have to issue more than blithe dismissals.

Ultimately, I don’t understand what’s so extraordinary about cryonics claims that they require such extraordinary evidence. They may be emotionally extraordinary, in that they really shake the way we think about life and death. But as critics of cryonics are keen to tell me, we don’t actually know nearly as much as we’d like about what the physical basis of long-term memory is and so whether or not the cryopreserved are information-theoretically dead, so the claim that they may well not be seems to me a long way from being scientifically extraordinary — in fact as far as the science goes it seems perfectly prosaic.

If you think they’re not information-theoretically dead, of course, that doesn’t imply that it might ever actually be practical to revive them. But to be that confident about what future technology won’t be able to do, especially given what the WBE roadmap presents — well, “extraordinary” isn’t quite the word, but it certainly seems like a strong claim, and one that would require a positive reason to believe it rather than the absence of a reason not to.

If my thinking on this is wrongheaded I welcome correction, so thanks again for commenting.

12.11.2010 13:04 Sam

I believe the argument that it might in thousands of years work is spurious — I think the call for well designed and documented impartial science is critical. This is not because I care one way or another whether it can be done but because the are people making profits (or at least their living/salaries etc) out of selling the hope. And if they treated it as te science fiction it appears to be, that would be fine but they are presenting their arguments as if they wer based on sound science. I am getting less surprised at the lack of sound science — why would a sound scientist sound the time when you cannot prove that in x thousand heads it could not be done. It is the exact argument the cryogenic movement use — and they said man would never go the moon. It is a faith issue unfortunately.

10.12.2010 23:10 Luke Parrish

<i>This is not because I care one way or another whether it can be done but because the are people making profits (or at least their living/salaries etc) out of selling the hope.</i>

If they are frequently getting paid less than they could elsewhere, does this affect your argument?

13.10.2010 1:57 bgwowk

CP,

I recently came across your remarks about our kidney cryopreservation experiments at 21st Century Medicine, and would like to correct a few misconceptions.

Re:


As for specific studies of vitrification: The rabbit kidney papers from 21st Century Medicine, which are sometimes cited as the best experimental evidence in support of vitrification at the organ level, are (scientifically speaking) a total nightmare: anecdotal, poorly controlled, reliant on tiny sample sizes, and focusing way too much attention on rare positive results.


This is a misleading characterization. Dr. Fahy has been working on kidney vitrification for more than 25 years, going back to the American Red Cross. The work at 21CM is a continuation of the progress that has been made over many hundreds of experiments, and five generations of vitrification solutions. This progress is documented in good papers from both institutions, the most comprehensive recent one being, “Cryopreservation of organs by vitrification: perspectives and recent advances”

http://www.21cm.com/pdfs/cryopreservation_advances.pdf

This paper explains in detail some of the problems that were overcome at 21CM allowing kidneys to be reproducibly recovered with long-term survival after transplantation as the sole kidney after cooling to temperatures of -22 degC or -45 degC. Each of many treatment groups had sufficient N numbers to show error bars documenting significant differences in outcome for the various treatments. The treatment that allowed survival after cooling to -45 degC had N=8, with tight error bars on the post-transplant serum creatinine time course.

Your assertion of poor experimental control is perplexing. In the above paper we show clear and reproducible differences in post-transplant morbidity and mortality as a function of different kidney treatments, including non-survival of the recipient animal when the kidney was not preserved well enough to support life. Also, the scientific context of these experiments is the extreme difficulty of obtaining survival of any kidney following exposure to sub-freezing temperatures, or cryoprotectant mixtures concentrated enough to prevent freezing at low temperatures. Without dialysis (which we do not do), a non-functioning sole kidney results in post-transplant serum creatinine rising without bound, and death within a few days regardless of medical support. We take these facts as common knowledge, but perhaps it is necessary for others to read earlier papers to appreciate how monumental the accomplishments described in this paper are.

Without this background, it is understandable how a cursory reading of the 2009 kidney vitrification paper

http://www.21cm.com/pdfs/12FahyORG5-3%5B1%5D.pdf

might appear anecdotal and difficult to interpret. The long-term survival of one vitrified kidney was indeed anecdotal. However we were justified in trying the experiment because after establishing our disciplined and hard-won platform at -45 degC, we finally had everything we needed to try the “moon shot” of going below the glass transition temperature and achieving vitrification at -130 degC. We were justified in publishing the positive anecdotal result because it was a major milestone to show that an organ as large and complex as a kidney could survive vitrification, even if just once. It was a demonstration of the intrinsic feasibility of something that had only been theoretical for a quarter century. It meant that there were no inherent obstacles to large and complex organs surviving and functioning after turning into a solid piece of glass. It was a very significant observation.


On another note, it would be nice to see a study from a group that doesn’t have a proprietary stake in the result. People with a profit motive have been known to misinterpret or misrepresent data — I’m not suggesting misconduct, of course, just pointing out that it’s very difficult to believe in a result when the only support comes from someone who might commercially benefit from the outcome.


That’s not really fair. 21CM functions in many respects like an academic research institution with few sources of commercial revenue. Our economic stake in the success of our organ cryopreservation experiments is the same as most academic researchers; persuading benefactors that our research merits continued funding. As a practical matter we are the only lab in the world doing research on vitrifying kidneys, or any large organs. Unfortunately there are no other labs setup right now to replicate this work. The surgical model alone takes years to develop.


The hippocampal slice data are somewhat more promising, but (a) these are very thin samples, and (b) the evidence of successful recovery focused intensely on histological detail rather than function.


This is not correct. The hippocampal slice paper documented successful preservation of histology and function (91 to 108% of controls) in brain slices that had been vitrified.

What does any of this have to do with cryonics? Certainly recovery of a rabbit kidney after vitrification, and recovery of isolated brain slices after vitrification, say almost nothing about what happens to whole human brains that are cryopreserved. The only connection of these experiments to cryonics is that similar cryoprotectant solutions(exactly the same solution in the case of the kidney) are used by Alcor for human cryopreservation. These solutions have exceptionally low toxicity compared to other cryoprotectant mixtures, so cryonicists are conscientiously using the least toxic solutions available to them.

What does this mean for the biology of cryonics? To understand what happens in actual human cryopreservation, we must look not to kidney cryopreservation research or isolated brain slices, but to whole brain cryopreservation experiments.

http://www.alcor.org/Library/pdfs/Lemler-Annals.pdf

http://www.alcor.org/Library/html/cambridge.html

Rabbit brains perfused with the same cryoprotectant mixture that humans are at all Alcor, and cooled at the same rate that human brains experience, show successful structural vitrification. Due to the long exposure time to cryoprotectants, it is not expected that functional viability is preserved. However if human brains behave as the rabbit brains, vitrification will be achieved, and structural damage from ice will be avoided. Diagnosing and repairing the adverse biochemical effects of the cryoprotectants, whatever they are, is among the burdens of future repair technology.

Generally I agree with you that cryonicists tend to underestimate the difficulty of the repair problem. It will certainly require centuries of advancement. Those who trivialize the problems either don’t understand them, or don’t understand how hard and slow of a process science really is.

10.02.2010 22:56 CP

There are limits to what one can address in a blog post, so I don’t feel like it’s fair play to call omission of whole-brain scanning and emulation, a strictly hypothetical technology that is well outside the mainstream of neuroscience, an “error.”

I can address the issue here, however:

The requirement of invoking yet another revolutionary technology, on top of the stringent technological requirements for preservation and revival — and possibly waiting a thousand years — just adds fuel to my central argument that cryonics advocates underestimate the difficulties of the challenge. In fact, there seem to be two revolutions required: the ability to obtain a useful map of the brain/mind (from a dead subject, if the technique used is destructive); and the ability to transfer it into another substrate, either biological or computational. These are both, to an experimentalist, “extraordinary” challenges. Calling them prosaic seems blithe, if you’ll pardon my use of the term.

The “roadmap” document is not scientifically convincing. The author has no expertise in experimental neuroscience (check out his list of publications; he is a modeler), and it shows in his estimation of the challenge of obtaining certain kinds of data. The proposed methods of scanning he describes on pp. 40-50 are all useful (within a limited context) for detecting histological or molecular detail, but none of them are capable, alone or in part, of compiling a comprehensive molecular description of a complex mixture of cells, each of which is in turn a complex mixture of proteins, lipids, nucleic acids, and other molecules.

The author is apparently ignorant of the real-world uses of these technologies, and perhaps as a result of this ignorance is guilty of overextrapolation so severe that it cripples the overall argument.

These techniques simply could not be used in the way they are proposed here, without waving the magic wand of a thousand years. I’m not “confident about what future technology won’t be able to do” (nor did I say I was), but I am confident that those passages do not advance the argument that this sort of “scanning” is feasible.

Furthermore, the author of the roadmap does not address the possibility that dynamic or nonequilibrium features of the physical brain might be important; he merely defines them out of existence. On p. 39, he identifies several features that his “scanning” methods would find difficult or impossible to assay — quite unsurprisingly, he considers these ‘very unlikely’ to be required for brain emulation. This kind of correlation, in which anything impossible also just happens to be unnecessary, raises red flags for the critical reader.

The reasons offered for eliminating these features from consideration are thin. The author’s discussion of “dynamical state” excludes nonequilibrium distributions of molecules that could not be captured or reconstituted in detail. The argument that loss of brain activity doesn’t destroy consciousness is unconvincing; the author is confusing electrical activity with cellular metabolic activity. The dismissal of quantum effects is based on arguments that have been falsified by recent observations of quantum behavior in macroscopic biological systems (e.g., photosynthesis).

I’ll leave the discussion of transferring/emulating the input of whole-brain scanning for another time.

In closing, I will grant that if <i>all we have to do</i> is figure out a way to lift consciousness out of a preserved brain and transfer it to another substrate, possibly waiting a thousand years, then I certainly can’t rule it out. I think this is where we’re in agreement: if we assume a truly astonishing level of technological progress, an unprecedented level of social stability (remember, we have to keep people’s substrates safe until the revolution), and wait a really long time, then anything is possible. I obviously have to grant that. So if that’s all you’re saying, then we agree.

My position is not that anything is “impossible”, but that cryonics advocates aren’t honest with themselves or their audience about how hard this would be. And the more I read — the more un-peer-reviewed, logically sloppy, over-extrapolated documents people send my way — the more convinced I am that I’m right to be very, very skeptical.

It’s way too early to be collecting money from people.

11.02.2010 8:12 Paul Crowley

The “roadmap” document is not scientifically convincing.

If you believe this, publish. The roadmap document has the imprimatur of Oxford University; a rebuttal setting out how it is overoptimistic would surely be of some note.

Also, please expand on what you say about photosynthesis. I’m not aware of anything in life that works anything like the way that ORCH-OR would have to work.

It’s way too early to be collecting money from people.

The timing is somewhat influenced by the fact that people are dying now.

Thanks again,

14.02.2010 19:58 David Gerard

<i>”The timing is somewhat influenced by the fact that people are dying now.”</i>

As a rationale for action, this appears to be the fallacy “Something must be done, this is something, therefore we must do this.”

There is no evidence whatsoever that what cryonicists are currently doing does any good at all or leaves anything preservable, any more than ancient Egyptian efforts to do the same for their pharaohs.

11.02.2010 12:07 Paul Crowley

To address some points in more detail

There are limits to what one can address in a blog post, so I don’t feel like it’s fair play to call omission of whole-brain scanning and emulation, a strictly hypothetical technology that is well outside the mainstream of neuroscience, an “error.”

If there are two routes out, and you write a critique of the very idea that there is a route out that only examines one of them, I think that is an error. If you meant to focus only on the plausibility of bodily reanimation, you didn’t say so.

The requirement of invoking yet another revolutionary technology, on top of the stringent technological requirements for preservation and revival

Scanning/WBE isn’t another requirement besides revival, it’s a standalone means of revival. Preservation and storage are already being done. So it’s not “yet another revolutionary technology” — if current cryo patients are amenable to scanning/WBE, that alone is a sufficient condition for cryo to work.

Furthermore, the author of the roadmap does not address the possibility that dynamic or nonequilibrium features of the physical brain might be important;

Later in this comment you reply to those passages where this possibility is addressed, so I’m not sure what you’re saying here.

quite unsurprisingly, he considers these ‘very unlikely’ to be required for brain emulation.

If you have reason to suspect otherwise I’d love to read more.

The reasons offered for eliminating these features from consideration are thin. The author’s discussion of “dynamical state” excludes nonequilibrium distributions of molecules that could not be captured or reconstituted in detail. The argument that loss of brain activity doesn’t destroy consciousness is unconvincing; the author is confusing electrical activity with cellular metabolic activity.

I frankly find the idea that long-term memory would depend on dynamical state implausible on the face of it; such a thing would be very hard to make robust compared to more straightforward mechanisms like morphological change. But if you have reason to think differently I would love to read more.

The dismissal of quantum effects is based on arguments that have been falsified by recent observations of quantum behavior in macroscopic biological systems (e.g., photosynthesis).

I’m astonished that you think that scanning/WBE is crazy talk, but ORCH-OR is a reasonable hypothesis that Bostrom and Sandberg should have given more weight to.

if we assume a truly astonishing level of technological progress,

I still feel like I’m a long way from understanding why the level of progress required would be “truly astonishing”. We don’t know how much progress is required, but there certainly seem to be plenty of plausible worlds where the progress required would be well short of that.

11.02.2010 18:29 CP

This conversation (and others I’ve had after publishing what will almost certainly be my last post on cryonics) have convinced me of one thing:

We’re prone to interpret the data as supportive of our prior conclusions. Where I see wishful thinking and sloppy argument, others see promise and feasibility. Without massively refiguring my own professional commitments, it’s doubtful that I’ll ever have time to comprehensively engage the subject — and even more doubtful that it would make a difference to committed believers on either side. In that sense, it reminds me of the conversations I had about religion back in my undergraduate days. Sound and fury, signifying nothing.

I’ll leave the last word to others. I do appreciate the consistently civil tone of the conversation. Best wishes.

12.02.2010 10:45 Paul Crowley

Confirmation bias certainly is a problem; if you’ve any ideas of anything I could be doing to combat it that I’m not already doing I’d be grateful to hear them. I think it’s a bit exaggeration to describe the situation as being as bad as it is with religion; and at least in that case there’s far more writing on both sides that you can refer a curious party to.

You refer to your “last post on cryonics” — have you done others? If so I’d love to read them.

One other note before I close off — let me again encourage you again to publish your critique of the WBE roadmap. If Oxford University are putting their seal over green-ink publications pretending to be science, someone should certainly be sounding the alarm.

I’m also glad of not being called names, so thanks :-) and thanks again for discussing this with me.

13.02.2010 1:31 enoonsti

Paul, I think he meant “last post” in the sense that he’s not going to write about this topic anymore, as per his statement:

Without massively refiguring my own professional commitments, it’s doubtful that I’ll ever have time to comprehensively engage the subject.”

…but considering the fact that 150,000 die per day, I would certainly hope he would deem it worth his time…

Chris, you’re absolutely right that you should not have the last word. You pretend there are no ethical problems with your position just so you can rest easy at night, and you especially blew your hand the moment you brought religion into this. Shame on you. I was particularly amused by Aschwin’s swipe at you: http://www.depressedmetabolism.com/2010/02/10/the-case-for-cryonics/

18.04.2010 13:20 David Matthewman

…but considering the fact that 150,000 die per day, I would certainly hope he would deem it worth his time…”

I’m not sure what point you’re making here. Why do you feel that that statistic is relevant to discussion of cryonics?

21.04.2010 16:21 Luke Parrish

I think it is relevant in that it implies that with the addition of some moderate industry our planet could be essentially death-free within a decade or so, even without near-term solutions to aging. It would also remain useful for other forms of death that are harder to cure than aging, such as extreme bodily trauma.

Support for cryonics could save lives — if it works. Opposition to cryonics could cost lives — if it works. Support or opposition won’t save or cost any lives if it doesn’t work. So treating it like it is unimportant strikes me as an assumption regarding the conclusion.

If the true answer is that we don’t know, I think it follows that it is an important topic worthy of learned debate and serious attention to serious detail by serious people.

22.04.2010 7:51 David Matthewman

I think it is relevant in that it implies that with the addition of some moderate industry our planet could be essentially death-free within a decade or so, even without near-term solutions to aging.”

Could you unpack that a little. In the face of it, that looks as though you’re proposing to vitrify around 150,000 per day. It that indeed your proposal, or have I misunderstood?

Support or opposition won’t save or cost any lives if it doesn’t work.”

If cryonics doesn’t work, then the resources that have been spent on making it work, including the individual sums of money that people have spent on getting themselves vitrified, could have been spent elsewhere. Some of those resources, if spent elsewhere, could have saved many lives. So I don’t think you can say that.

I do accept that the benefits to those who are in a position to be vitrified may (if cryonics works) be seen to outweigh the costs of developing successful cryonics, but I don’t think blanket statements that it has no costs at all are supportable.

24.04.2010 16:59 Luke Parrish

It would be naive to say that there are no costs or that economic costs have no effect on human lives. But this is the same as arguing that a magazine subscription or a chewing gum habit is killing people. Essentially you are just saying that something with no direct utility that is just fun to have is taking money away from pursuits that would directly save lives.

A problem with that argument is that it doesn’t account for indirect benefits, only indirect costs. For example, I get the impression that cryonics would have positive cultural influence in the direction of rationality and science, and against superstition. Even a slight tendency in this direction could easily offset the economic trade-offs in terms of lives saved.

I do think cryonics can and should be practiced on a large scale. But please note that costs don’t scale up directly. The square-cube law creates some really huge economies of scale when it comes to cryogenic storage.

Stabilization is a different matter; it would be practiced in hospitals or hospices, and thus compete somewhat for medical resources. On the other hand, undertakers put out of a job might be recruited to stabilization, so it wouldn’t necessarily have much effect on available labor pool. In fact, an indirect benefit we might expect to see is more undertakers going into the medical field rather than “wasting” their entire careers caring for the dead, due to the fact that stabilization more closely resembles medical practice than undertaking does.

Note that current stabilization costs reflect infrequent use of equipment, unpredictable traveling conditions, and other diseconomies resulting from the small scale it is practiced on.

4.08.2011 13:33 Paul Crowley

Anti-cryonics blog post: http://nowebsite.co.uk/blog/2011/08/cryonics/

Meets 0 of the 4 criteria in my open letter http://blog.ciphergoth.org/blog/2010/02/14/an-open-letter-to-scientific-critics-of-cryonics/ but nice to see all the same.

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