BASIC programs to compute source densities from autoradiographic cross-fire matrices.

Area of Science:

• Quantitative EM autoradiography
• Mathematical modeling
• Image analysis

Background:

• Accurate source density computation is crucial for quantitative EM autoradiography.
• Existing methods may have limitations in fitting silver grain distributions.
• Microcomputer-based analysis offers accessibility and efficiency.

Purpose of the Study:

• To develop and present two distinct mathematical procedures for computing source densities.
• To implement these procedures using BASIC programs for desk-top microcomputers.
• To compare a non-iterative least-squares method with an iterative chi-square minimization method.

Main Methods:

• Development of a non-iterative linear least-squares procedure.
• Implementation of an iterative method minimizing chi-square using the Gauss-Newton algorithm.
• Utilizing BASIC programs for microcomputer-based analysis of cross-fire matrices and silver grain distributions.

Main Results:

• Successful implementation of both least-squares and iterative methods for source density computation.
• Demonstration of fitting hypothetical silver grain distributions to observed data.
• The iterative Gauss-Newton method provides a robust approach for chi-square minimization.

Conclusions:

• The developed mathematical procedures and associated microcomputer programs enhance quantitative EM autoradiography analysis.
• Both methods offer viable options for source density calculation, with the iterative method providing chi-square minimization.
• This work facilitates more precise analysis of electron microscopy autoradiography data.