Weakly nonlinear plane waves are considered in hyperelastic crystals. Evolution equations are derived at a quadratically nonlinear level for the amplitudes of quasi-longitudinal and quasi-transverse waves propagating in arbitrary anisotropic media. The form of the equations obtained depends upon the direction of propagation relative to the crystal axes. A single equation is found for all propag...

Using the Very Large Array, we have detected radio emission from the site of SN 1970G in the Sc galaxy M101. These observations are 31 years after the supernova event, making SN 1970G the longest monitored radio supernova. With flux densities of 0.12± 0.020 mJy at 6 cm and 0.16± 0.015 mJy at 20 cm, the spectral index of −0.24 ± 0.20 appears to have flattened somewhat when compared with the prev...

The development of a particular wintertime atmospheric circulation regime over the North Atlantic, comprising a northward shift of the North Atlantic eddy-driven jet stream and an associated strong and persistent ridge in the subtropics, is investigated. Several different methods of analysis are combined to describe the temporal evolution of the events and relate it to shifts in the phase of th...

the iranian “new wave” filmmakers started to pay attention to social changes during the pahlavi regime. imperial pahlavi successfully suppressed his political oppositions in decade of 1332-1342 (hijri shamsi) and spread a social reform during the following decades in 40’s to 50’s. the iranian cinematic movement that was called new wave by some persian film critics because of its similarly to th...