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Author Topic:   Foundations of ID
Wounded King
Member
Posts: 4149
From: Cincinnati, Ohio, USA
Joined: 04-09-2003


Message 25 of 213 (203339)
04-28-2005 10:58 AM
Reply to: Message 24 by CK
04-28-2005 10:47 AM


Re: A few questions.
Can someone clear this up for me - Are we talking about scientists who are Christian or are we talking about people who are members of 'The Church of Christ, Scientist'?
I'm sure a case could be made that members of 'The Church of Christ, Scientist' are not generally part of the mainstream of science.
TTFN,
WK

This message is a reply to:
 Message 24 by CK, posted 04-28-2005 10:47 AM CK has replied

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Wounded King
Member
Posts: 4149
From: Cincinnati, Ohio, USA
Joined: 04-09-2003


Message 38 of 213 (203577)
04-29-2005 6:03 AM
Reply to: Message 37 by Parasomnium
04-29-2005 5:50 AM


Re: Debunking some nonsense
You can see why he'd be confused, its easy to mistake a single photon for a Cadillac. Quantum weirdness seems to be getting a whole lot weirder in this thread.
TTFN,
WK

This message is a reply to:
 Message 37 by Parasomnium, posted 04-29-2005 5:50 AM Parasomnium has replied

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Wounded King
Member
Posts: 4149
From: Cincinnati, Ohio, USA
Joined: 04-09-2003


Message 44 of 213 (203638)
04-29-2005 11:21 AM
Reply to: Message 40 by Limbo
04-29-2005 9:13 AM


If the designer is the observer of quantum mechanics, then the act of observing the right place at the right time could be the mechanism.
That hardly constitutes a mechanism. Are you saying that the 'observer' can choose which point mutations occur? What large scale genomic rearrangements occur, can he use his observation to skew probability to such an extent that a whole irreducibly complex system can suddenly be created ex-nihilo?
Is there any reason to assume that there is any observing entity other than human consciousness? Where are the experiments performed in the absence of conscious human participation? I am reminded of a Greg Egan story 'Quarantine' in which the premise is that only humans can collapse wave functions and by doing so they are capable of damaging other entities with less limited perspectives on the universe. Sorry if I spoiled the story there for anyone reading it at the moment.
Is there any reason not to assume that everything outside of the universe we can observe either directly or indirectly is not one forever unresolved sea of probability?
TTFN,
WK

This message is a reply to:
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Wounded King
Member
Posts: 4149
From: Cincinnati, Ohio, USA
Joined: 04-09-2003


Message 168 of 213 (207078)
05-11-2005 11:20 AM
Reply to: Message 157 by Jerry Don Bauer
05-11-2005 9:40 AM


Jerry writes:
What environment could possible cause homochiral proteins to form our of a racemic mixture of amino acids against the laws of chemistry?
I doubt that any could cause it to happen "against the laws of chemistry" but there certainly seem to be a few which might cause it to happen.
For instance the adsorption of one particular isomeric form of amino acids by minerals. In this case different faces show selectivity for different enantiomers.
Selective adsorption of L- and D-amino acids on calcite: Implications for biochemical homochirality.
Hazen RM, Filley TR, Goodfriend GA.
Proc Natl Acad Sci U S A. 2001 May 8;98(10):5487-90.
The emergence of biochemical homochirality was a key step in the origin of life, yet prebiotic mechanisms for chiral separation are not well constrained. Here we demonstrate a geochemically plausible scenario for chiral separation of amino acids by adsorption on mineral surfaces. Crystals of the common rock-forming mineral calcite (CaCO3), when immersed in a racemic aspartic acid solution, display significant adsorption and chiral selectivity of D- and L-enantiomers on pairs of mirror-related crystal-growth surfaces. This selective adsorption is greater on crystals with terraced surface textures, which indicates that D- and L-aspartic acid concentrate along step-like linear growth features. Thus, selective adsorption of linear arrays of D- and L-amino acids on calcite, with subsequent condensation polymerization, represents a plausible geochemical mechanism for the production of homochiral polypeptides on the prebiotic Earth.
I added the emphasis in bold to certain salient portions of the abstract.
Alternatively it may be that your assumption of equilibrium is not neccessarily warranted.
Recycling Frank: Spontaneous emergence of homochirality in noncatalytic systems
Raphal Plasson, Hugues Bersini and Auguste Commeyras
PNAS 2004 November 30, vol. 101, no. 48, pp.16733-16738
In this work, we introduce a prebiotically relevant protometabolic pattern corresponding to an engine of deracemization by using an external energy source. The spontaneous formation of a nonracemic mixture of chiral compounds can be observed in out-of-equilibrium systems via a symmetry-breaking phenomenon. This observation is possible thanks to chirally selective autocatalytic reactions (Frank's model) [Frank, F. C. (1953) Biochim. Biophys. Acta 11, 459—463]. We show that the use of a Frank-like model in a recycled system composed of reversible chemical reactions, rather than the classical irreversible system, allows for the emergence of a synergetic autoinduction from simple reactions, without any autocatalytic or even catalytic reaction. This model is described as a theoretical framework, based on the stereoselective reactivity of preexisting chiral monomeric building blocks (polymerization, epimerization, and depolymerization) maintained out of equilibrium by a continuous energy income, via an activation reaction. It permits the self-conversion of all monomeric subunits into a single chiral configuration. Real prebiotic systems of amino acid derivatives can be described on this basis. They are shown to be able to spontaneously reach a stable nonracemic state in a few centuries. In such systems, the presence of epimerization reactions is no more destructive, but in contrast is the central driving force of the unstabilization of the racemic state.
This paper describes stereoselective reactions such as the formation of N-carboxyanhydrides of amino acids, as part of the activation reaction, which favour the subsequent formation of homochiral peptides.
TTFN,
WK
This message has been edited by Wounded King, 05-11-2005 11:23 AM

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