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On using a double-exponential model for describing faecal marker concentration curves.

M S Dhanoa·J France·R C Siddons
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Abstract

A mathematical and numerical appraisal of the double-exponential model is presented, with particular reference to its ability to reproduce preset values of biological measures such as rumen and whole-tract mean retention times and faecal production rate. A complete, formal mathematical derivation is provided, with consideration given to a solution to the model when the two smallest rate constants are equal. It is concluded that any error introduced by using an approximation in deriving the double-exponential form is negligible in practice, and that the double exponential in logarithmic form is able to determine the relevant biological measures quite satisfactorily and speedily.

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M S Dhanoa, J France, R C Siddons. 1989-11-21. On using a double-exponential model for describing faecal marker concentration curves.. https://doi.org/10.1016/s0022-5193(89)80020-7

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