Side-bending same direction

It is now instructive to ask why the achiral calamitic SmC a (or SmC) is not antiferroelectric. Cladis and Brand propose a possible ferroelectric state of such a phase in which the tails on both sides of the core tilt in the same direction, with the cores along the layer normal. Empirically this type of conformational ferroelectric minimum on the free-energy hypersurface does not exist in known calamitic LCs. Another type of ferroelectric structure deriving from the SmCA is indicated in Figure 8.13. Suppose the calamitic molecules in the phase were able to bend in the middle to a collective free-energy minimum structure with C2v symmetry. In this ferroelectric state the polar axis is in the plane of the page. 

Fig. 2.23 When r , which points from the neutral atom to the ion, lines up in the same direction as the applied field F, the potential energy of the system is reduced on one side by the field. Thus the compound ion, in one of its vibrational states, can dissociate by particle tunneling. If r is anti-parallel to F, then the potential energy bends upward, and field dissociation becomes impossible. The direction of r is denoted by the arrow of the He - Rh2+ bond.

Type II dysfunctions follow Fryette s second principle of physiologic motion, which states that when side-bending occurs from a hyper-flexed or hyperextended (non-neutral) position, rotation and side-bending of one segment are in the same direction. These are single vertebral dysfunctions and are often pathologic in nature. The involved vertebra will be found to be either flexed or extended on the vertebra below it and side-bent and rotated to the same side. Type II dysfunctions are more often traumatic in origin. 

FIG. 5-12 (A) Type II sIde-bendIng and rotation In same direction. (B) Type I sIde-bendIng and rotation In opposite directions. 

When a cervical vertebra side-bends, it also rotates in the same direction. A somatic dysfunction will exhibit restrictions in side-bending and... 

T1 and possibly T2 may be treated in much the same manner as the typical cervical vertebral somatic dysfunctions, with the exception that the rotation and side-bending are into the same direction. Although the primary position of application is with the patient seated, the patient may also be treated in the side-lying position. Compression is used for both. Occasionally, the portion of the treatment involving movement towards the barriers may result in an articulatory "pop." The descriptions are for the specific sidebending and rotation components with flexion and extension as modifications into the appropriate directions. 

Rotation occurs on the same axis as torsion however, the sphenoid and occiput rotate in the same direction. Rotation occurs toward the side of the convexity, which is relatively inferior. Sidebending and rotation dysfunctions are named for the convexity of the side-bending motion. 

Inspection of the barrel and screw for wear can provide information on the root cause for the wear. For example, if wear occurs at an axial location on only one side of the barrei and on all sides (angular direction) of the screw, then the likely root cause is that the barrel is out of alignment at that axial location. Conversely, if the barrei is worn on all sides and the screw is worn on only one side at the same axial location, then the root cause is likely a local bend in the screw. 

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