Shuffling of atoms

If this is subjected to the "Bain strain" it becomes an undistorted b.c.c. cell. This atomic "switching" involves the least shuffling of atoms. As it stands the new lattice is not coherent with the old one. But we can get coherency by rotating the b.c.c. lattice planes as well (Fig. 8.8). 

In the development of unit plastic relaxation events by the triggered STs, Demkowicz and Argon noted that in the intense internal shuffle of atomic environments in the STs that result in a net transformation shear strain the atom environments change their character chaotically from LL to SL and vice versa by an apparent random mechanical mixing of environments, with

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At such small scales, the experimenters cannot see the motor working by any means except an electron microscope. Although the motor is simple conceptually, its precision is incredible—it operates at the atomic level, controlling the motion of atoms as they shuffle back and forth between nanoparticles. B. C. Regan, Zettl, and their colleagues published the report Surface-Tension-Driven Nanoelectromechani-cal Relaxation Oscillator in Applied Physics Letters in 2005. As the researchers note in their report, [SJurface tension can be a dominant force for small systems, as illustrated in their motor. This is a prime example of the different forces and situations that must be taken into account in the nanoworld. 

Abstract—Pseudo-twinning and mechanical twinning have been observed in a transmission electron microscopy study of TiMNi47Fe3 and Ti49Ni5i alloys which have the B2(CsCI) structure. Observation of twinning in ordered alloys is rare and this is the first observation of twinning reported in a B2 structure. The twin planes are the 112 and 114 planes. For 112 pseudo-twins, the composition plane is not the twin plane and the pseudo-twin does not have the B2 structure. For 114 mechanical twins, the composition plane is the twin plane and the twin does have the B2 structure. It is shown that a shear on the 114 plane plus a shuffle of the atoms results in the ordered B2 structure in the twinned region. 

Cysteine residues form disulfide bonds, which are important to protein structural integrity. Shuffling of these bonds, where two sulfur atoms from two different amino acid molecules link up, often changes the 3D structure, causing a loss of activity. 

The second mode of toxicity is postulated to involve the direct interaction of the epidithiodiketopiperazine motif with target proteins, forming mixed disulfides with cysteine residues in various proteins. Gliotoxin, for example, has been demonstrated to form a 1 1 covalent complex with alcohol dehydrogenase [13b, 17]. Epidithiodi-ketopiperazines can also catalyze the formation of disulfide bonds between proxi-mally located cysteine residues in proteins such as in creatine kinase [18]. Recently, epidithiodiketopiperazines have also been implicated in a zinc ejection mechanism, whereby the epidisulfide can shuffle disulfide bonds in the CHI domain of proteins, coordinate to the zinc atoms that are essential to the tertiary structure of that domain, and remove the metal cation [12d, 19],... 

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