Physiological time and time-invariance.

N M van Straalen

doi:10.1016/0022-5193(83)90111-x

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Physiological time and time-invariance.

N M van Straalen

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Abstract

An operational definition of physiological time is suggested that involves a non-linear transformation of a physical time-scale such that a certain temperature-dependent process becomes time-invariant. The definition expresses that physiological time has the dimension of time, and can be measured in units such as days or weeks. It is shown that the quantification of a physiological time-scale requires the specification of an arbitrary constant, which equals the rate of change of the process in physiological time. When the process-rate also depends on some internal variable, the interaction of this variable with temperature must be multiplicative, if a single physiological time-scale is to be used. The relationship with conventional uses of physiological time is discussed. The time-scale, as defined here, reduces to degree-day summation or development accumulation if certain multiplicative constants are deleted.

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Animals Models, Biological Physiology Temperature Time Journal Article Research Support, Non-U.S. Gov't

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N M van Straalen. 1983-10-07. Physiological time and time-invariance.. https://doi.org/10.1016/0022-5193(83)90111-x

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