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The Langmuir-Blodgett film technique is currently being researched as a deposition process for many optical applications. The performance of these coatings is dependent on both the quality of deposition and the film structure. A structural investigation, using transmission electron diffraction and microscopy, on materials with potential for second harmonic generation and optical data storage is reported on this paper. Transmission electron diffraction patterns are presented for an optically non- linear stilbene derivative. Results indicate that monolayer quality is good but for the formation of multilayers causes the film quality to deteriorate. The technique of alternating this material with tricosanoic acid has improved deposition, and electron microscopy has been used to indicate this. High quality transmission electron diffraction patterns of tricosanoic acid are interpreted in terms of a pseudo- hexagonal packing arrangement with a grain size of approximately 5 μm. Organic dyes which absorb in the near-IR have also been studied. These have potential for use in ablative optical hole burning for optical data storage. Electron diffraction results are presented, showing good structure, with a grain size suitable for this application.

Langmuir-Blodgett (LB) films have been produced using a novel near-IR- absorbing dye based on 1,4-naphthoquinone. Wavelength compatibility with semiconductor diode lasers makes it particularly suitable for optical storage applications. Ablative data marks have been recorded using 830 nm light with a pulse energy of 3.6 nJ. The sensitivity is dependent on heat flow within the film and substrate, and can be increased using LB film buffer layers.

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A case of partial heart-block is reported in the course of which there occurred frequent attacks of syncope with convulsive seizures (Adams-Stokes' syndrome). During the period of observation barium chloride, epinephrin and atropine were administered,—all without appreciable effect. The patient died during an attack of ventricular asystole. Postmortem examination showed a lesion involving junctional tissues and consisting of a fatty and lymphocytic infiltration of the atrioventricular node and the first part of the bundle of His together with a fibrotic process involving both left and right bundle-branches. The bundle fibers showed degeneration. That this degeneration was active, was evidenced by the finding of endotheliocytes which were phagocyting the degenerating Purkinje fibers. We suggest that our failure to establish an idioventricular rhythm might have been due to the presence of extensive destruction of junctional tissues in a patient in whom the lower pacemaker had never been dominant.