Response to Dr. Satish Kalhan:
I appreciate Dr. Kalhan’s kind words about my paper [1]. The derivation he provides in his letter is quite correct under the Tracee Steady State assumption, consistent with my equation (7) as he says. However, his formulas here differ slightly from the paper I referred to [2]. In his letter, Dr. Kalhan correctly has (IxEi) in the denominator for fraction of infused tracer oxidized and “I” in the formula for Ra. However, in the 1998 paper [2], both the denominator for tracer fraction oxidized (F) and the formula for Ra have only “I”; the same error is seen in two of the other papers Dr. Kalhan mentions [3, 4]. I do see that the formulas are given correctly in one of the references [5]. Apparently, there were typographical errors in the other three articles.
Footnotes
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References
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