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Temperature and electrophysiology?

r norman rsn_ at _comcast.net
Mon Dec 27 19:09:33 EST 2004

On Mon, 27 Dec 2004 17:51:06 GMT, "kenneth collins"
<kenneth.p.collins at worldnet.att.net> wrote:

>"r norman" <rsn_ at _comcast.net> wrote in message news:ppd0t0l3kv1tjatr8j95rtdg42l6lmmop4 at 4ax.com...
>| On 27 Dec 2004 08:01:23 -0800, tehgabriel at web.de (tomte) wrote:
>| >Hi!
>| >
>| >I had a debate with a collegue of mine, wether an increase of
>| >temperature from 34.5°C to 36°C may lead to significantly different
>| >effects in whole-cell patch-clamp recordings (I refer to experiments
>| >on rat brain slices).
>| >Of course there's no question that one may obtain different results
>| >when experiments were done at 10°C or 20°C. But what's the situation
>| >in the special case i mentioned at the beginning (sligthly
>| >temp.difference in a regime close to body temperature).
>| >What's your opinion/experience?
>| >
>| >Any comment would be appreciated
>| >Cheers,
>| >Thomas
>| >
>| >p.s.:
>| >I would be very grateful for references
>| A process with a Q10 of 2 (rate doubles for a 10C increase in
>| temperature) would change by less than 4% for a 1/2 degree change.  If
>| the process were even more  temperature sensitive, a Q10 of 5, say, it
>| would change by about 8% for the same temperature change.
>| A change of several degrees would produce small but noticeable
>| changes.  But a fraction of a degree is another story. In most cases
>| it would be hard to control the temperature to such a fine degree.
>| Then, note that body temperature is not really constant, but
>| fluctuates with time of day, metabolic state, health, etc.  Even brain
>| temperature in mammals, generally regulated much more finely than core
>| body temperature, will fluctuate. It is unlikely that small changes
>| will produce any significant changes in function that are meaningful
>| to the cell even though they may be detected by a cell physiologist.
>Hi Dr. Norman,
>Before I "disagree", do I need to express
>the esteem in which I hold you? :-]
>It's =way= up-there.
>But I do =Respectfully= disagree that even
>the slightest variation of temperature is not
>significant with respect to the 3-D energy-
>dynamics that occur within nervous sys-
>Yes, the brain is awesomely vasculated,
>and that carries off excess heat, but
>even such can only proceed in accord
>with the body temp set-point, which is
>varied in "fever" dynamics.
>This's important be-cause of the long-
>standing known facts of the shifting of
>the black body power spectrum toward
>its high-frequency 'end' as TempK is
>increased. This corresponds rigorously
>to a variation in "vibrational" frequency
>at the 'atomic' level, and the rigorously-
>correlated functional variability stands
>verified [if, thus far, unrecognized as be-
>ing what it, in fact, is :-]
>At the level of molecular dynamics small
>changes in "vibrational" frequency =must=
>result in relatively-large variations in func-
>tionality. [The "shampoo experiment" dis-
>closes [rigorously] why it must be so.]
>As I've reiterated in long-former posts,
>it's a virtual certainty that this is some
>of why "fever" is a functional "mode"
>that's been 'engineered' into the Biology
>by evolutionary dynamics.
>One can even perceive the "washed-
>out-ness" that's happening within one
>while one is enduring "fever" -- I mean,
>one can literally perceive that one's
>thought processes, for instance, are
>not occurring 'normally' -- that they
>are "washed-out" -- that "thought" be-
>comes relatively 'powerless'.
>There has to be something of great
>worth for it to be so routinely "pur-
>chased" at so great a "price".
>And what's going on is falt-out-ob-
>vious within 3-D energydynamics
>that I've not yet discussed. [I was
>going to discuss them if I'd not been
>'tossed-out' of sci.physics.research.]
>The DNA is "addressed" differentially
>with respect to body temp, and, per-
>haps more-importantly, so is the DNA
>and molecular processes of disease
>Again, my hypothesis is that elevations
>in body temp impose disorder upon
>the molecular functionalities of disease
>agents, which, in and of itself, because
>it's so 'atomically'-generalized, is prob-
>ably insufficient to get the disease-de-
>struction job done, but it definitely
>makes the job of immune-system ag-
>ents easier by, literally, "shoving"
>things in the direction of disorder [in
>the direction of WDB2T] -- in this,
>literally pointing-the-Direction in
>which immune-system molecular dyn-
>amics are to 'move'.
>Some new hardware needs to be
>developed to do it, but everything
>that I've discussed in this post is
>Some of what's in my "disagreement" is
>in-there be-cause of what's been my
>Failure to carry the discussion of NDT
>and TH forward sufficiently.
>I've been carefully monitoring the col-
>lective amygdalar "speed-limit", trying
>not to "violate" it, but my doing so has
>kept the discussion from getting, rapidly,
>to where it, ultimately, needs to "go".
>Part of it is that I rewrote Physics, but
>no one else understands that rewritten
>stuff yet.
>[It'd be easier in-person. :-]
>Cheers, Dr. Norman, ken [k. p. collins]

I appreciate your sentiments about my contributions here.

Your own work, as you well know, deviates rather substantially from
classical "doctrine."  Although my politics is rather distinctly
different, in technical terms about matters of science I am a very
traditional conservative, hewing closely to the "party line".  You do
say you "rewrite Physics, but no one else understands that rewritten
stuff yet."  I agree you rewrote something and the no one else
including me understands it.  Unfortunately, some of your arguments,
such as the ones here regarding energy, black-body radiation, and
vibrational frequencies are rather a bit off the mark (in my
old-fashioned traditional view).  And these tend to be very
off-putting when making decisions on how much time to spend going over
you material.

A change of 1/2 degree C is less than a 0.2% change in absolute
temperature.  There is no significant change in black body radiation
that occurs as a result -- Stefan's law says that the total energy
emitted would increase by less than 1% (fourth power relationship) and
Wien's law says the peak wavelength would change less than 0.2%
(inverse proportionality).  These won't make any significant changes
in anything.  The wavelengths are already deep in the infrared and
would just very slightly modify some molecular vibrations.  Again,
these types of variations are trivial compared with the normal
temperature fluctuations experienced by neurons in everyday life.

There do exist situations where the system has singular points or
bifurcations and very small changes in a system parameter (like T)
makes sudden large changes in behavior.  There is no known physical
chemistry like that for changes in cellular biochemicals showing a
state or functional transition in the 30 - 40 C range.  And for good
reason -- as I pointed out, the cells are constantly subject to these
fluctuations.  Furthermore, all cellular processes in neurons are
shared widely across the animal kingdom, including animals whose
brains function well across extreme temperature changes -- 0 C to 30
or 40 C.  

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