X-Message-Number: 4632
Date: Sun, 16 Jul 1995 19:47:51 -0700
From:  (Ted Skrecky)
Subject: Re: message #4574

Date: Thu Jul 13 02:15:58 1995
From:  (Doug Skrecky)
Subject: cryonet reply
To: 


Ted, could upload the following message to the cryonet? thx
________________________________________________

From: Doug Skrecky 
Newsgroups: sci.cryonics 
Subject: Re: why is deep freezing necessary? 
Date: 

    In message 4574 Brian Wowk writes: "Foods do not stay fresh
indefinitely in refrigerators or even deep freezers. Traces of liquid
water within which diffusion can occur remain inside cells all the way
down to -120'C.  Below this temperature the last traces of liquid water
will vitrify (become as viscous as glass), and only then will all
molecules be locked in place and unable to react. Long-term storage of
biological materials therefore requires temperatures of -130'C or lower.
Liquid nitrogen (cheap and convenient) is -196'C." 
    I would like to add my own 2 cents to this. Brian illustrates one way
to obtain stable storage of biological materials. He shows that the
deleterious effects of liquid water can be eliminated by lowering the
temperature sufficiently to solidify the water. An alternative more
straight forward method would be to eliminate the problems associated with
liquid water by eliminating the water itself. There exist a number of
creatures which can survive complete desiccation and enter a state called
anhydrobiosis (or life without water).  Provided these are shielded from
moisture and oxygen they can apparently survive indefinitely at room
temperature. The current record for longevity of anhydrobiotic organisms
is some bacterial spores sealed inside amber. These have been revived
after over 25 million years of storage. *1
    In a way it is unfortunate that temperature reduction instead of
desiccation has been chosen for preserving bodies. Cryonics by its very
nature is only a short-term solution which is completely dependant on the
replenishing of liquid nitrogen which boils away. Although I am speaking
as a cryonics skeptic here, I believe there is a great deal of agreement
among cryonicists as well with my claim that maintaining cryonic storage
for more than 200 years will likely prove to be very difficult.
Anhydrobiosis suffers from no such limitations. Whether if takes 50, 200
or even 2000 years or more to develop and perfect reanimation technology
is a matter of complete indifference to a body appropriately prepared,
freeze-dried, then stored in a titanium armoured time capsule and then
(what the heck) buried in the permafrost. 
    Anhydrobiosis is the ONLY method capable of truly long-term storage of
biological materials. 

*1 "Revival and Identification of Bacterial Spores in 25 to 40 Million 
Year Old Dominican Amber" 1060-1064 Vol.268 May 19,1995 Science


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