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From Mr M. J. Coleman Sir: As a former pupil, it saddens me to see the continued use of one man's bitter personal experience to blacken both the name of [...]

Background: Mammographic screening for breast cancer not only reduces the overall mortality from breast cancer but allows greater opportunities for breast-conserving operations. The predicted degree of breast conservation is not being realized, but is increasing in centres that have published their results.
Methods: The operative management of breast cancers diagnosed by BreastScreen Central and Eastern Sydney Screening and Assessment Service were compared between two time periods: January 1988-December 1992 (group 1) and January 1993-December 1995 (group 2). The rate of breast conservation, and other data were compared between the two periods. An attempt was made with multivariate analysis to identify some of the factors that made mastectomy rather than conservation more likely.
Results: There were 723 cancers detected that were suitable for analysis (group 1, n = 273; group 2, n = 450). In group 1 the breast conservation rate was 42.9%; this increased significantly to 60.4% in group 2 (P < 0.001). The data were examined to determine if there was any other factor that had changed over the time periods which might account for the increased rate of breast conservation. The use of pre-operative diagnostic techniques such as fine needle aspirate cytology and core biopsy increased significantly. Multivariate analysis comparing the differences in patient age, diagnostic technique, tumour type, grade, size, location and lymph node status, both independently and compositely did not account for the increase in breast conservation in group 2.
Conclusion: The increase in breast conservation is due to other factors such as the surgeons' approach and patient attitude. The use of pre-operative, minimally invasive tissue sampling techniques is increasing.

We discuss the dynamics of a piecewise holonomic mechanical system: a discrete sister to the classical non-holonomically constrained Chaplygin sleigh. A slotted rigid body moves in the plane subject to a sequence of pegs intermittently placed and sliding freely along the slot; motions are smooth and holonomic except at instants of peg insertion. We derive a return map and analyze stability of constant-speed straight-line motions: they are asymptotically stable if the mass center is in front of the center of the slot, and unstable if it lies behind the slot; if it lies between center and rear of the slot, stability depends subtly on slot length and radius of gyration. As slot length vanishes, the system inherits the eigenvalues of the Chaplygin sleigh while remaining piecewise holonomic. We compare the dynamics of both systems, and observe that the discrete skate exhibits a richer range of behaviors, including coexistence of stable forward and backward motions.

Discusses various techniques to get good grain in photographs. Altering grain; Push-processing; Reticulation; Micro enlargement; Controlled reciprocity failure; Paper negatives; Multiple exposure.