Low T/E: What It Means

Aw, heck, as soon as I finish I see two errors: C-13 is not radioactive, and
both E and T are eliminated primarily by the kidneys, not the liver.

I still need to find out why synthetic T has fewer C-13 atoms than natural
T.

--
Bruce Wilson KF7K
http://science.uvsc.edu/wilson
"Bruce Wilson" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

There has been many questions over the past few weeks about where the T/E
ratio comes from, and what it means.

So here's what I've been able to dig up on it. Please keep in mind I'm a
chemist, not a physician, and they'd probably look at it differently.

T/E Ratio:
The process of making testosterone actually makes two different forms. The
active form, testosterone, is different from the inactive form,
epitestosterone, by the placement of a bond. Both forms are made by the
same process, at typically a 1:1 ratio (there is a 50:50 chance the bond
goes one way, making T, or the other way, making E; it's called chemical
isomerism). So in a cell making all its own T, there should be roughly the
same amount of E, because both of them are removed from the cells at the
same rate by the same process (liver oxidation, half life = 1-2 days).

If someone has added exogenous ("of outside origin"😉 testosterone, the
T-making cells will sense that there is too much T, and slow down the
T-making process. In doing so the cells also slow down the E-making
process, so the E-levels drop, but the T-levels stay high because
(presumably) a lot of it was added to the body. Hence the test for T/E
ratio; excess T depresses the amount of E made. Since there is no known
physiological reason for the T/E ratio to be high, the presumption is that
any T/E ration that is high must be from doping.

By 2000 it seems that dopers figured this out, and started doping with 1:1
T:E. E is harmless, so they just went ahead and added some, and thus kept
the ratio right.

So scientists (chemists) needed a new way to test. The new test was to
determine the origin of the carbon in the testosterone.

Carbon Isotope:
Atmospheric carbon, the carbon that goes into plants, then into our diet,
has about 1% carbon-13; thus the carbon our bodies should also be 1% C-13.
Most carbon is carbon-12, but some carbon is created high in the
atmosphere when nitrogen is bombarded by cosmic rays, creating carbon-13.
Carbon-13 weighs just a bit more than C-12, so if you can isolate the
molecules of testosterone and weigh them (using mass spectrometry), you
can see a difference in weight between "natural" T and "synthetic" T;
natural T weighs just a bit more, since synthetic T is made from crude oil
and does not contain any C-13 (the C-13 that was in the fresh oil millions
of years ago has long ago decayed; did I mention that C-13 was
radioactive?). This is the carbon isotope test. It's a rather difficult
test to do, but with care can differentiate a clear case of doping. If a
small amount of T is taken the differentiation is a bit more difficult.

Sadly, labs don't publish the actual scientific results, so I don't know
and can't calculate the statistical probability that Landis doped with
exogenous T. In the end all the lab can determine is the probability. It's
never really a black or white call by the chemist. Sad to say, but it
really is up to the lawyers to make the decision.

If I got anything wrong, sorry, and I'll be glad to fix it.
--
Bruce Wilson KF7K
http://science.uvsc.edu/wilson

"Bruce Wilson" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

There has been many questions over the past few weeks about where the
T/E ratio comes from, and what it means.

So here's what I've been able to dig up on it. Please keep in mind I'm
a chemist, not a physician, and they'd probably look at it
differently.

T/E Ratio:
The process of making testosterone actually makes two different forms.
The active form, testosterone, is different from the inactive form,
epitestosterone, by the placement of a bond. Both forms are made by
the same process, at typically a 1:1 ratio (there is a 50:50 chance
the bond goes one way, making T, or the other way, making E; it's
called chemical isomerism). So in a cell making all its own T, there
should be roughly the same amount of E, because both of them are
removed from the cells at the same rate by the same process (liver
oxidation, half life = 1-2 days).

If someone has added exogenous ("of outside origin"😉 testosterone, the
T-making cells will sense that there is too much T, and slow down the
T-making process. In doing so the cells also slow down the E-making
process, so the E-levels drop, but the T-levels stay high because
(presumably) a lot of it was added to the body. Hence the test for T/E
ratio; excess T depresses the amount of E made. Since there is no
known physiological reason for the T/E ratio to be high, the
presumption is that any T/E ration that is high must be from doping.

By 2000 it seems that dopers figured this out, and started doping with
1:1 T:E. E is harmless, so they just went ahead and added some, and
thus kept the ratio right.

So scientists (chemists) needed a new way to test. The new test was to
determine the origin of the carbon in the testosterone.

Carbon Isotope:
Atmospheric carbon, the carbon that goes into plants, then into our
diet, has about 1% carbon-13; thus the carbon our bodies should also
be 1% C-13. Most carbon is carbon-12, but some carbon is created high
in the atmosphere when nitrogen is bombarded by cosmic rays, creating
carbon-13. Carbon-13 weighs just a bit more than C-12, so if you can
isolate the molecules of testosterone and weigh them (using mass
spectrometry), you can see a difference in weight between "natural" T
and "synthetic" T; natural T weighs just a bit more, since synthetic T
is made from crude oil and does not contain any C-13 (the C-13 that
was in the fresh oil millions of years ago has long ago decayed; did I
mention that C-13 was radioactive?). This is the carbon isotope test.
It's a rather difficult test to do, but with care can differentiate a
clear case of doping. If a small amount of T is taken the
differentiation is a bit more difficult.

Sadly, labs don't publish the actual scientific results, so I don't
know and can't calculate the statistical probability that Landis doped
with exogenous T. In the end all the lab can determine is the
probability.

Based on an estimate from one study, Floyd is 5.25 standard deviations
from the natural mean on the isotope test. Pretty damning if you believe
the accuracy of the test.

Quoted message said:

It's never really a black or white call by the chemist. Sad to say, but
it really is up to the lawyers to make the decision.

If I got anything wrong, sorry, and I'll be glad to fix it.
--
Bruce Wilson KF7K
http://science.uvsc.edu/wilson

Thanks for the info Bruce.

Phil H

Phil Holman' piholmanc@yourservice said:

"Bruce Wilson" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

There has been many questions over the past few weeks about where the
T/E ratio comes from, and what it means.

So here's what I've been able to dig up on it. Please keep in mind I'm
a chemist, not a physician, and they'd probably look at it
differently.

T/E Ratio:
The process of making testosterone actually makes two different forms.
The active form, testosterone, is different from the inactive form,
epitestosterone, by the placement of a bond. Both forms are made by
the same process, at typically a 1:1 ratio (there is a 50:50 chance
the bond goes one way, making T, or the other way, making E; it's
called chemical isomerism). So in a cell making all its own T, there
should be roughly the same amount of E, because both of them are
removed from the cells at the same rate by the same process (liver
oxidation, half life = 1-2 days).

If someone has added exogenous ("of outside origin"😉 testosterone, the
T-making cells will sense that there is too much T, and slow down the
T-making process. In doing so the cells also slow down the E-making
process, so the E-levels drop, but the T-levels stay high because
(presumably) a lot of it was added to the body. Hence the test for T/E
ratio; excess T depresses the amount of E made. Since there is no
known physiological reason for the T/E ratio to be high, the
presumption is that any T/E ration that is high must be from doping.

By 2000 it seems that dopers figured this out, and started doping with
1:1 T:E. E is harmless, so they just went ahead and added some, and
thus kept the ratio right.

So scientists (chemists) needed a new way to test. The new test was to
determine the origin of the carbon in the testosterone.

Carbon Isotope:
Atmospheric carbon, the carbon that goes into plants, then into our
diet, has about 1% carbon-13; thus the carbon our bodies should also
be 1% C-13. Most carbon is carbon-12, but some carbon is created high
in the atmosphere when nitrogen is bombarded by cosmic rays, creating
carbon-13. Carbon-13 weighs just a bit more than C-12, so if you can
isolate the molecules of testosterone and weigh them (using mass
spectrometry), you can see a difference in weight between "natural" T
and "synthetic" T; natural T weighs just a bit more, since synthetic T
is made from crude oil and does not contain any C-13 (the C-13 that
was in the fresh oil millions of years ago has long ago decayed; did I
mention that C-13 was radioactive?). This is the carbon isotope test.
It's a rather difficult test to do, but with care can differentiate a
clear case of doping. If a small amount of T is taken the
differentiation is a bit more difficult.

Sadly, labs don't publish the actual scientific results, so I don't
know and can't calculate the statistical probability that Landis doped
with exogenous T. In the end all the lab can determine is the
probability.

Based on an estimate from one study, Floyd is 5.25 standard deviations
from the natural mean on the isotope test. Pretty damning if you believe
the accuracy of the test.

You would also have to know something about the distribution of the
mean here in order to know that this is damning evidence.

In article <[email hidden]>,

Bruce Wilson said:

There has been many questions over the past few weeks about where the T/E
ratio comes from, and what it means.

So here's what I've been able to dig up on it. Please keep in mind I'm a
chemist, not a physician, and they'd probably look at it differently.

Hi,

I'm not a chemist, but I still think I've written a much more thorough
review of the isotope test. Since you are a chemist, I'd love for you
to review it and comment on it:

http://hea-www.harvard.edu/~fine/opinions/testosterone_d13C.html

tom

Doug Anderson said:

Phil Holman' piholmanc@yourservice said:

"Bruce Wilson" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

There has been many questions over the past few weeks about where the
T/E ratio comes from, and what it means.

So here's what I've been able to dig up on it. Please keep in mind I'm
a chemist, not a physician, and they'd probably look at it
differently.

T/E Ratio:
The process of making testosterone actually makes two different forms.
The active form, testosterone, is different from the inactive form,
epitestosterone, by the placement of a bond. Both forms are made by
the same process, at typically a 1:1 ratio (there is a 50:50 chance
the bond goes one way, making T, or the other way, making E; it's
called chemical isomerism). So in a cell making all its own T, there
should be roughly the same amount of E, because both of them are
removed from the cells at the same rate by the same process (liver
oxidation, half life = 1-2 days).

If someone has added exogenous ("of outside origin"😉 testosterone, the
T-making cells will sense that there is too much T, and slow down the
T-making process. In doing so the cells also slow down the E-making
process, so the E-levels drop, but the T-levels stay high because
(presumably) a lot of it was added to the body. Hence the test for T/E
ratio; excess T depresses the amount of E made. Since there is no
known physiological reason for the T/E ratio to be high, the
presumption is that any T/E ration that is high must be from doping.

By 2000 it seems that dopers figured this out, and started doping with
1:1 T:E. E is harmless, so they just went ahead and added some, and
thus kept the ratio right.

So scientists (chemists) needed a new way to test. The new test was to
determine the origin of the carbon in the testosterone.

Carbon Isotope:
Atmospheric carbon, the carbon that goes into plants, then into our
diet, has about 1% carbon-13; thus the carbon our bodies should also
be 1% C-13. Most carbon is carbon-12, but some carbon is created high
in the atmosphere when nitrogen is bombarded by cosmic rays, creating
carbon-13. Carbon-13 weighs just a bit more than C-12, so if you can
isolate the molecules of testosterone and weigh them (using mass
spectrometry), you can see a difference in weight between "natural" T
and "synthetic" T; natural T weighs just a bit more, since synthetic T
is made from crude oil and does not contain any C-13 (the C-13 that
was in the fresh oil millions of years ago has long ago decayed; did I
mention that C-13 was radioactive?). This is the carbon isotope test.
It's a rather difficult test to do, but with care can differentiate a
clear case of doping. If a small amount of T is taken the
differentiation is a bit more difficult.

Sadly, labs don't publish the actual scientific results, so I don't
know and can't calculate the statistical probability that Landis doped
with exogenous T. In the end all the lab can determine is the
probability.

Based on an estimate from one study, Floyd is 5.25 standard deviations
from the natural mean on the isotope test. Pretty damning if you believe
the accuracy of the test.

You would also have to know something about the distribution of the
mean here in order to know that this is damning evidence.

True, but 5.25 SD's is a lot. Tchebyshev's (or Chebyshev's) theorem {1}
(true for ANY distribution) tells us that at least 96.3% of data in any
population lies within 5.25 SD's of the mean, i.e. at most 3.7% of data
lies beyond 5.25 SD's.

By contrast, if we knew the distribution was normal, we would have fewer
data (by several orders of magnitude) outside 5.25 SD's.

Given that Tchebyshev's theorem is an extremly blunt instrument
(universal instruments often are), 5.25 SDs, **IF TRUE**, is certainly
cause for serious concern.

Mark J.

[1] One summary found by google:
http://library.thinkquest.org/10030/3smodcm.htm

Bruce Wilson said:

Aw, heck, as soon as I finish I see two errors: C-13 is not radioactive, and
both E and T are eliminated primarily by the kidneys, not the liver.

I still need to find out why synthetic T has fewer C-13 atoms than natural

Because it comes from soy?

Ron

Bruce Wilson said:

I still need to find out why synthetic T has fewer C-13 atoms than
natural T.

Google "isotopic fractionation plants" or something like that. Substitute
soybeans for plants if you want to get really detailed about it. They make
synth T from soybeans.

--
Bill Asher

"Doug Anderson" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

Phil Holman' piholmanc@yourservice said:

"Bruce Wilson" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

There has been many questions over the past few weeks about where
the
T/E ratio comes from, and what it means.

So here's what I've been able to dig up on it. Please keep in mind
I'm
a chemist, not a physician, and they'd probably look at it
differently.

T/E Ratio:
The process of making testosterone actually makes two different
forms.
The active form, testosterone, is different from the inactive form,
epitestosterone, by the placement of a bond. Both forms are made by
the same process, at typically a 1:1 ratio (there is a 50:50 chance
the bond goes one way, making T, or the other way, making E; it's
called chemical isomerism). So in a cell making all its own T,
there
should be roughly the same amount of E, because both of them are
removed from the cells at the same rate by the same process (liver
oxidation, half life = 1-2 days).

If someone has added exogenous ("of outside origin"😉 testosterone,
the
T-making cells will sense that there is too much T, and slow down
the
T-making process. In doing so the cells also slow down the E-making
process, so the E-levels drop, but the T-levels stay high because
(presumably) a lot of it was added to the body. Hence the test for
T/E
ratio; excess T depresses the amount of E made. Since there is no
known physiological reason for the T/E ratio to be high, the
presumption is that any T/E ration that is high must be from
doping.

By 2000 it seems that dopers figured this out, and started doping
with
1:1 T:E. E is harmless, so they just went ahead and added some, and
thus kept the ratio right.

So scientists (chemists) needed a new way to test. The new test was
to
determine the origin of the carbon in the testosterone.

Carbon Isotope:
Atmospheric carbon, the carbon that goes into plants, then into our
diet, has about 1% carbon-13; thus the carbon our bodies should
also
be 1% C-13. Most carbon is carbon-12, but some carbon is created
high
in the atmosphere when nitrogen is bombarded by cosmic rays,
creating
carbon-13. Carbon-13 weighs just a bit more than C-12, so if you
can
isolate the molecules of testosterone and weigh them (using mass
spectrometry), you can see a difference in weight between "natural"
T
and "synthetic" T; natural T weighs just a bit more, since
synthetic T
is made from crude oil and does not contain any C-13 (the C-13 that
was in the fresh oil millions of years ago has long ago decayed;
did I
mention that C-13 was radioactive?). This is the carbon isotope
test.
It's a rather difficult test to do, but with care can differentiate
a
clear case of doping. If a small amount of T is taken the
differentiation is a bit more difficult.

Sadly, labs don't publish the actual scientific results, so I don't
know and can't calculate the statistical probability that Landis
doped
with exogenous T. In the end all the lab can determine is the
probability.

Based on an estimate from one study, Floyd is 5.25 standard
deviations
from the natural mean on the isotope test. Pretty damning if you
believe
the accuracy of the test.

You would also have to know something about the distribution of the
mean here in order to know that this is damning evidence.

OK, we would also have to have more than just Floyds 3.99 reading. This
was just an estimate but here are some of the details of the study.
A normal value of delta 13C was -21.3 to -24.4.
An enhanced value was -27.43 +/- 0.76 mean and S.D. with a range
between -26.18 and -30.04.

Phil H

In article <[email hidden]>,

Phil Holman piholmanc@yourservice said:

OK, we would also have to have more than just Floyds 3.99 reading. This
was just an estimate but here are some of the details of the study.
A normal value of delta 13C was -21.3 to -24.4.
An enhanced value was -27.43 +/- 0.76 mean and S.D. with a range
between -26.18 and -30.04.

That was one study. I've seen different ranges from other studies.
Make sure to check how many people were in their study. Taken
together, the ranges I've seen for natural and synthetic testosterones
overlap. An absolute number is worthless for detecting doping, and
even the WADA people are smart enough to see that.

So I think you might misunderstand Floyd's 3.99 reading. It doesn't
mean that he jumped up 3.99 per mil, it means his testosterone
was 3.99 per mil higher than some other natural steroid. This
is supposed to eliminate issues with baseline value and diet.

tom

"Bruce Wilson" <[email hidden]> wrote in message
news:[email hidden]...
so if you can isolate the molecules of

Quoted message said:

testosterone and weigh them (using mass spectrometry), you can see a
difference in weight between "natural" T and "synthetic" T; natural T
weighs

Dum question - how hard is it to isolate the T molecules? What influence
could that have on the test? Smaller sample means greater potential error
from contamination no? You'd figure that just about everything you pee has
carbon in it no?

-Andy B.

I was very interested in your reference 13. 10 minute liver metabolism is
fast! I'm not sure what they means to the rate of T production, because if
any blood-borne T was metabolized at that rate, we'd need to make a lot of
it daily (for a hormone, that is).

In all your is a really good write up getting at the difficulties of the
C-13 isotope test.

I still haven't found a definitive answer to why the C-13/C-12 ratio
changes, but here's what I've gotten: the 13/12 ratio is lower in
plant-derived testosterone than human-derived testosterone probably because
plants have a long "refinement" process (many synthetic steps) and in most
steps the C-12 rate of reaction is a bit faster than the C-13 rate; combined
there is a slight selection for C-12-containing hormone precursors. We
humans (well, mammals in general), having more advanced biochemistry, can
synthesize our hormones from a more diverse set of precursors, and thus are
less selective for C-12, so our 13/12 ratio is higher. I'd hate to have to
prove this in the lab, though. These are very small differences.

--
Bruce Wilson KF7K
http://science.uvsc.edu/wilson
"Thomas A. Fine" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

In article <[email hidden]>,

Bruce Wilson said:

There has been many questions over the past few weeks about where the T/E
ratio comes from, and what it means.

So here's what I've been able to dig up on it. Please keep in mind I'm a
chemist, not a physician, and they'd probably look at it differently.

Hi,

I'm not a chemist, but I still think I've written a much more thorough
review of the isotope test. Since you are a chemist, I'd love for you
to review it and comment on it:

http://hea-www.harvard.edu/~fine/opinions/testosterone_d13C.html

tom

"Bruce Wilson" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

There has been many questions over the past few weeks about where the T/E
ratio comes from, and what it means.

snip

Quoted message said:

Carbon Isotope:
Atmospheric carbon, the carbon that goes into plants, then into our diet,
has about 1% carbon-13; thus the carbon our bodies should also be 1% C-13.
Most carbon is carbon-12, but some carbon is created high in the
atmosphere when nitrogen is bombarded by cosmic rays, creating carbon-13.
Carbon-13 weighs just a bit more than C-12, so if you can isolate the
molecules of testosterone and weigh them (using mass spectrometry), you
can see a difference in weight between "natural" T and "synthetic" T;
natural T weighs just a bit more, since synthetic T is made from crude oil
and

snip

Synthetic steroids are synthetically altered steroidal type molecules of
plant origin. Synthesis of the steroid nucleus from scratch is more
difficult and expensive than taking a plant based sterol (see soy as an
example from Bill Asher's post) and chemically modifying it as necessary.
The chemical modifications utilize carbon sources derived ultimately from
crude oil/natural gas starting sources.

Just a few years ago, I saw data stating that nearly 50% of all prescription
drugs start with precursors of plant origin. I believe they meant that half
of all prescriptions filled utilize a medication that is initially of plant
origin rather than 50% of the different marketed medications utilize plants
as a starting material for the synthetic process.
-Mike

Hormones can be separated as a group from other chemicals in urine
chemically, then the hormones separated from each other using a technique
called chromatography. Chromatography at its simplest) is adding all the
chemicals to one end of a strip of paper, then letting a solvent (water, for
example) carry the chemicals across the strip. Chemicals that aren't
attracted to the paper move pretty fast, but chemicals that are attracted to
the paper move more slowly. In the end you have separated each chemical from
the rest. (In reality the separation is done in a very narrow, long column
filled with very small beads coated with a substance known to separate one
class of compounds well, and either the chemicals pushed through at very
high pressure [HPLC, high pressure liquid chromatography] or the column is
heated past the boiling point of the chemicals and gas pushes them through
the column [GC, gas chromatography]).

The isotope separation is done by vaporizing the testosterone, giving the
molecules a slight charge, then accelerating them through a bend. The
lighter C-12 molecules can make the bend sharper then the heavier C-13
molecules, and the deltaC13 ratio is calculated from the relative sizes of
the two peaks. This is called mass spectroscopy, and it is a very good
technique.

--
Bruce Wilson KF7K
http://science.uvsc.edu/wilson
"Andy B." <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

"Bruce Wilson" <[email hidden]> wrote in message
news:[email hidden]...
so if you can isolate the molecules of

Quoted message said:

testosterone and weigh them (using mass spectrometry), you can see a
difference in weight between "natural" T and "synthetic" T; natural T
weighs

Dum question - how hard is it to isolate the T molecules? What influence
could that have on the test? Smaller sample means greater potential error
from contamination no? You'd figure that just about everything you pee has
carbon in it no?

-Andy B.

In article <[email hidden]>,

Bruce Wilson said:

I was very interested in your reference 13. 10 minute liver metabolism is
fast! I'm not sure what they means to the rate of T production, because if
any blood-borne T was metabolized at that rate, we'd need to make a lot of
it daily (for a hormone, that is).

I'd welcome additional info. It seemed really fast to me also. It's
not a great reference because it's not a study on that subject. But it's
not a bad reference either, since it's a professional article.

Quoted message said:

I still haven't found a definitive answer to why the C-13/C-12 ratio
changes, but here's what I've gotten: the 13/12 ratio is lower in
plant-derived testosterone than human-derived testosterone probably because
plants have a long "refinement" process (many synthetic steps) and in most
steps the C-12 rate of reaction is a bit faster than the C-13 rate; combined
there is a slight selection for C-12-containing hormone precursors. We
humans (well, mammals in general), having more advanced biochemistry, can
synthesize our hormones from a more diverse set of precursors, and thus are
less selective for C-12, so our 13/12 ratio is higher. I'd hate to have to
prove this in the lab, though. These are very small differences.

Photosynthesis tends to reject carbon-13. Here's a good description of
why that I just came across:

http://www.madsci.org/posts/archives/2003-06/1055532737.Bc.r.html

But there are two types of photosynthesis. C3 plants, which is most
things that we eat, use a kind of photosynthesis that rejects a lot
of carbon-13 (-22 to -30 per mil). C4 plants, including corn, millet,
sugar cane, and pineapples, rejects less carbon-13 (-10 to -14 per
mil). Since our diet is a mixture, we end up with a value somewhere
in between. Meat animals tend to be fed a lot of corn and millet
so that may also tend to lift the amount of carbon-13 we have (those
of us who aren't vegetarians), though that's less clear.

As far as minor variance among our own natural steroids, it could be
that our chemistry does some fractionation, like photosynthesis, though
much more subtle. Or it could be different rates of production and
metabolism coupled with minor variations in diet. Or it could be that
different steroids are produced from a different set of inputs, which
tend to come from one or another kind of food. Probably all three.

And finally, synthetic testosterone is derived from soy which for unknown
reasons is on the low end of the carbon-13 range among C3 plants, being
generally close to -30 per mil.

tom

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In article <[email hidden]>,

(Thomas A. Fine) said:

And finally, synthetic testosterone is derived from soy which for unknown
reasons is on the low end of the carbon-13 range among C3 plants, being
generally close to -30 per mil.

Low and high should be defined. In fact soy fixes less C13
than almost any plant. If we think of photosynthetic
carbon fixing as a fractionation column, soy does the best
job of refining C12 from C13 than any food plant. C4
plants fractionate more than C3 plants by a factor of two.

--
Michael Press

In article <[email hidden]>,

Michael Press said:

In article <[email hidden]>,

(Thomas A. Fine) said:

And finally, synthetic testosterone is derived from soy which for unknown
reasons is on the low end of the carbon-13 range among C3 plants, being
generally close to -30 per mil.

Low and high should be defined.

In this case I meant low as in "low in carbon-13". This can be
confusing because of the negative numbers, although strictly
speaking a larger negative number is lower, also, so it SHOULDN'T
be confusing. And yet it is.

Quoted message said:

In fact soy fixes less C13
than almost any plant. If we think of photosynthetic
carbon fixing as a fractionation column, soy does the best
job of refining C12 from C13 than any food plant. C4
plants fractionate more than C3 plants by a factor of two.

This is wrong. C4 plants fractionate less than C3 plants. They
end up with more carbon-13 than C3 plants (but still less than
what's in the air). I think there's been a lot of confusion about
this.

So assume:

rm = measured 13C/12C ratio
re = standared 13C/12C ratio, based on background levels (re = 0.0112372)

This is the equation for delta 13C:

(rm - re)
------------ X 1000
re

As your carbon-13 falls, rm falls, and the d13C value becomes more negative.

Let's look more closely at this, as there's also another source of
confusion.

This means that normally there are 11.2372 parts of carbon-13 for every
thousand carbon-12s. If you only had 10 parts of carbon-13 for every
thousand carbon-12s, then your d13C would be: -110

Compared to the carbon-12, you only dropped 1.237 parts per thousand
parts of carbon-12. But compared to the expected amount of carbon-13,
you dropped 110 parts out of every 1000 carbon-13s you expected to
find. Based on the standard value of 0.0112372, you would expect to
find 1000 carbon-13 atoms along with 88990 carbon-12 atoms. But in the
above example of -110 per mil, you would find 88990 carbon-12 atoms and
890 carbon-13 atoms, or 110 less than the expected 1000.

A d13C of -1000 would mean there's no carbon-13. A value of 1000 would
mean that there's double the expected carbon-13.

tom

"Mike Owens" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

Just a few years ago, I saw data stating that nearly 50% of all
prescription drugs start with precursors of plant origin. I believe they
meant that half of all prescriptions filled utilize a medication that is
initially of plant origin rather than 50% of the different marketed
medications utilize plants as a starting material for the synthetic
process.

A lot of chemical drugs are made by biotech processes that essentially grow
a yeast in a high efficiency vat. The yeast has had its DNA modified to
include a gene for making the specific chemical under question. This makes a
very accurate reproduction that can be made very cheaply and very rapidly
leaving the fermenter ready to make something else in just a couple of days.

We could make high quality wine in a week better than that stuff aged 10
years.

Tom Kunich' cyclintom@yahoo. com said:

"Mike Owens" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

Just a few years ago, I saw data stating that nearly 50% of all
prescription drugs start with precursors of plant origin. I believe they
meant that half of all prescriptions filled utilize a medication that is
initially of plant origin rather than 50% of the different marketed
medications utilize plants as a starting material for the synthetic
process.

A lot of chemical drugs are made by biotech processes that essentially grow
a yeast in a high efficiency vat. The yeast has had its DNA modified to
include a gene for making the specific chemical under question. This makes a
very accurate reproduction that can be made very cheaply and very rapidly
leaving the fermenter ready to make something else in just a couple of days.

LIVEDRUNK ALERT! LIVEDRUNK ALERT! LIVEDRUNK ALERT!

Quoted message said:

We could make high quality wine in a week better than that stuff aged 10
years.

LIVEDRUNK ALERT! LIVEDRUNK ALERT! LIVEDRUNK ALERT!

This is not a drill. This is an actual LIVEDRUNK ALERT! Please attend to this
very important matter immediately.

Ron

RonSonic said:

LIVEDRUNK ALERT! LIVEDRUNK ALERT! LIVEDRUNK ALERT!

Dumbass,
Unfortunately we are currently drunk and cannot respond to any alerts,
segmentation faults or blue screens. If you get back to us later we may be
able to help depending on how hungover we are.