This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via CrossRef Citing Articles via Google Scholar Google Scholar Articles by Rygiewicz, P. T. Articles by Glass, A. D. M. Search for Related Content PubMed PubMed Citation Articles by Rygiewicz, P. T. Articles by Glass, A. D. M. Agricola Articles by Rygiewicz, P. T. Articles by Glass, A. D. M.

Articles

A Comparison of Methods for Determining Compartmental Analysis Parameters ¹

College of Forest Resources, University of Washington, Seattle, Washington 98195, Botany Department, University of British Columbia, Vancouver, British Columbia V6T 2B1 Canada

The traditional method for determining compartmental analysis parameters relies on a visual selection of data points to be used for regression of data from each cellular compartment. This method is appropriate when the compartments are kinetically discrete and are easily discernible. However, where treatment effects on compartment parameters are being evaluated, a more objective method for determining initial parameters is desirable.

Three methods were examined for determining initial isotopic contents and half-times of ⁸⁶Rb elution from cellular compartments using theoretical data with known parameters. Experimental data from roots of Douglas fir (Pseudotsuga menziesii [Mirb.] Franco) and barley (Hordeum vulgare L.) intact seedlings were also used. The three methods were a visually assisted, linear regression on data of semilog plot of isotope elution versus time, a microcomputer-assisted, linear regression on semilog plot where maximization of the square of the correlation coefficient (r²) was the criterion to determine data points needed for each regression and a mainframe computer-assisted, direct nonlinear regression on elution data using a model of the sum of three exponential decay functions. The visual method resulted in the least accurate estimates of compartmental analysis parameters. The microcomputer-assisted and nonlinear regression methods calculated the parameters equally well.

³ Copies of the r² maximization microcomputer program may be obtained by writing directly to A.D.M. Glass.

¹ Supported by National Science Foundation grant DEB-8004629 to C.S.B. and Natural Sciences and Engineering Research Council of Canada grant 67-0570 to A.D.M.G.

This article has been cited by other articles:

				E. Cholewa and C. A. Peterson Evidence for Symplastic Involvement in the Radial Movement of Calcium in Onion Roots Plant Physiology, April 1, 2004; 134(4): 1793 - 1802. [Abstract] [Full Text] [PDF]