From the viewpoint of grain boundary structure a small-angle symmetric tilt boundary can be considered a boundary that is symmetrically mis-oriented by a small angle from a perfect Σ=1 boundary. The misoriention in these boundaries occurs during the re-crystallization period when annealing of the deformed material helps to develop the boundary. The development of the boundary occurs mainly by t...

We predict new features for the evolution of noncanonical screw wave-front dislocations nested in diffracting light beams. The evolution equations for the location of single-charge dislocations are derived, and their consequences are elaborated by use of illustrative examples. It is shown that the dynamic trajectories of the vortices can be controlled by adjustment of the noncanonical strength ...

Simultaneous, bilateral, anterior dislocations of the glenohumeral joint are rare, most attributable to major trauma. Seizure disorders and electrocution are a common cause of glenohumeral and fracture dislocations although these are most commonly posterior injuries. We present an interesting case report of diagnosis and treatment of an active duty sailor with bilateral anterior shoulder fractu...

Bilateral shoulder dislocations are rare, and if they occurred, posterior type of dislocations is common. Bilateral anterior shoulder dislocations are very rare and occur due to trauma with unique mechanism of injury. We report a case of unreduced simultaneous bilateral anterior dislocations of shoulder without associated fractures in a forty-year-old man following a unique mechanism of injury;...

In quasicrystals, there are not only conventional, but also phason displacement fields and associated Burgers vectors. We have calculated approximate solutions for the elastic fields induced by two-, threeand fivefold straight screwand edge-dislocations in infinite icosahedral quasicrystals by means of a generalized perturbation method. Starting from the solution for elastic isotropy in phonon ...

We investigate the formation of misfit dislocations in strained heteroepitaxial crystal growth and their influence on the structure of the growing layers. We use Kinetic Monte Carlo simulations for an off-lattice model in 1+1 dimensions with Lennard-Jones interactions. Two different types of the formation of dislocations are found, depending on the sign and the magnitude of the misfit. Misfit d...

The dominant mechanism for creating large irreversible strain in atomic crystals is the motion of dislocations, a class of line defects in the crystalline lattice. Here we show that the motion of dislocations can also be observed in strained colloidal crystals, allowing detailed investigation of their topology and propagation. We describe a laser diffraction microscopy setup used to study the g...