Service life and survivability of aircraft structures

We present a methodology aimed at guaranteeing high fatigue and crack-growth resistance of aircraft structures in Russia and formulate criteria of survivability of these structures and requirements to the materials intended for the use in designed structures. We also analyze the methods used for the solution of the problem of safe operation of old aircrafts which take into account the degradation of fatigue and crack-growth resistance of structural materials and suggest a solution of the problem of multiple-origin cracks for aircraft structures in Russia. Central Institute of Aerohydrodynamics (TsAGI) Zhukovskii, 140160, Moscow Region, Russia. Translated from Fizyko-Khimichna Mekhanika Materialiv, Vol. 32, No. 2, pp. 43–56, March–April, 1996.     

Software for automated follow-up of chronic outpatients

A service program for selecting magnifying means has been developed and tried in 59 patients (110 eyes) with senile maculodystrophy and cataracts. Attempts at choosing traditional magnifiers (magnifying glasses, hyperoculars, telescopic eyeglasses, and contact lens-eyeglasses system) were made with due consideration for the focus of lesions and the anatomooptic parameters of the eye (corneal refraction, size of the anteroposterior axis, and clinical refraction). The results indicate that the proposed program helped effectively choose traditional magnifiers for the majority (81.35%) of the above patient population.     

Tooth fragment reattachment: an alternative for restoration of fractured anterior teeth

The development of advanced adhesive systems has made it possible to bond various substrates, e.g., composite resin and vital or nonvital tooth structures. The management of coronal and coronoradicular fractures in the maxillary region with these adhesive materials is easier, safer, and more efficacious than the use of traditional treatment alternatives that involve the use of posts and cores and/or other mechanical devices to obtain retention. Ability to bond the dislocated segment of the fractured tooth constitutes a significant step forward in the management of this clinical condition.