Mechano-Activated Self-Immolation of Hydrogels via Signal Amplification.

Cellular organisms possess intricate mechano-adaptive systems that enable them to sense forces and process them with (bio)chemical circuits for functional adaptation. Inspired by such processes, this study introduces a hydrogel system capable of mechanically activated and chemically transduced self-destruction. Our judiciously designed hydrogels can mechanically generate radicals that are processed and amplified in a self-propagating radical de-crosslinking reaction, ultimately leading to mechanically triggered self-immolation.

Cell Adhesion on UV-Crosslinked Polyurethane Gels with Adjustable Mechanical Strength and Thermoresponsiveness.

Temperature-responsive polyurethane (PU) hydrogels represent a versatile material platform for modern tissue engineering and biomedical applications. However, besides intrinsic advantages such as high mechanical strength and a hydrolysable backbone composition, plain PU materials are generally lacking bio-adhesive properties. To overcome this shortcoming, the authors focus on the synthesis of thermoresponsive PU hydrogels with variable mechanical and cell adhesive properties obtained from linear precursor PUs based on poly(ethylene glycol)s (pEG) with different molar masses, isophorone diisocyanate, and a dimerizable dimethylmaleimide (DMMI)-diol.

Correlating laser damage tests.

This paper reports on efforts to correlate two commercially oriented laser damage tests. The two test facilities are located at Hughes Aircraft Co. and Montana Laser Optics*.

1.06-microm laser damage of thin film optical coatings: a round-robin experiment involving various pulse lengths and beam diameters.

A number of commercially available optical coatings, both antireflective and high reflective, have been tested for their laser-induced damage threshold, involving a total of eight different laboratories. The results obtained and the experimental methods used at these laboratories were discussed among the participants in this round robin at a minisymposium held at Balzers, Liechtenstein, 9-10 Dec. 1982.

Measurement of optical coupling coefficients based on thermal expansion.

A fundamentally new method for measuring optical coupling coefficients is described. A sample of a particular shape is subjected to a fixed tensile load and heated with pulsed optical radiation. The resulting peak tensile relaxation is proportional to the total absorbed energy; evolution of the coupling coefficient may thus be observed.