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Biomedical subjects

M W Frohlich

Publications and source records attributed to M W Frohlich.

2 recordsLinked to original sources

PATHMASTER: modelling differential diagnosis as "dynamic competition" between systematic analysis and disease-directed deduction.

PATHMASTER is an expert system under development to assist in teaching histopathologic differential diagnosis. The system incorporates two "orthogonal" representations of the knowledge required to perform differential diagnosis. One representation groups histopathologic features around the anatomic structures of liver tissue, the second representation groups the features around the diseases in which they occur. Using these two representations, PATHMASTER models the process of diagnosis as a "dynamic competition" between systematic analysis and disease-directed deduction. By varying two parameters of PATHMASTER's underlying mathematical model, the interplay between these factors can be varied.

Algorithms

Birefringent objects visualized by circular polarization microscopy.

In the standard polarizing microscope, birefringent material appears bright only if its optic axis is oblique to the axes of the polarizer and analyzer filters; consequently, an object may be visualized as several disconnected bright regions. This confusing appearance is avoided if the crossed plane polarizers of the conventional microscope are replaced by circular polarizers of opposite handedness. All orientations of the optic axis in the focal plane then become equivalent; objects generally appear uniformly bright. Ordinary microscopes are easily modified to use this technic with readily available components.

Birefringence