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Biomedical subjects

H J Frisch

Publications and source records attributed to H J Frisch.

3 recordsLinked to original sources

Pattern recognition at the Fermilab collider and Superconducting Supercollider.

In a colliding beam accelerator such as Fermilab or the Superconducting Supercollider (SSC) protons, or antiprotons, collide at a rate between 10(5) (Fermilab) and 10(8) (SSC) collisions per second. In real time experimentalists have to select those events which are candidates for exploring the limit of known phenomena at a much lower rate, 1-100 per second, for recording on permanent media. The rate of events from new physics sources is expected to be much lower, as low as a few per year. This is a severe problem in pattern recognition: with an input data stream of up to 10(15) potential bits per second in its images, we have to pick out those images that are potentially interesting in real time at a discrimination level of 1 part in 10(6), with a known efficiency. I will describe the overall filtering strategies and the custom hardware to do this event selection (a.k.a. pattern recognition).

Journal Article↗

[The importance of puncture cytology in diagnosis of benign and malignant breast changes].

In 500 mamma needle biopsies that were cytologically examined we found a precision of 87.4%, with 2.6% false negative, and 6.2% false positive results. In 19 cases a cytological diagnosis was not possible resulting in a sensitivity of 0.94 and a specificity of 0.86. False positive findings were due to misinterpretations of the cytological pictures, as were also false negative findings. In the latter cases sampling mistakes could also be the reason. Cytological diagnostic should only be made using triple diagnostic technique since the methods are complementary to each other in respect to their diagnostic security. Practical experience in the puncturing technique as well as an experienced cytologist are prerequisites using this method successfully as a diagnostic tool.

Biopsy, Needle↗