Helical buckling

Since the force F, is positive (compressive), a helical buckling of tubing is expected above the packer. 

Fig. 7. Complex forms resulting from snap-buck after break, (a) General view of splitting with helical buckling, (b) Detail of break zone, (c) Kink-bands due to axial compression on recoil.

PALINDROME A length of DNA containing inverted repeat sequences capable of buckling to form a base-paired loop with either strand or both strands of previously linear, helical DNA. 

Chatellier, J. Buckle, A.M. Fresht, A.R. GroEL recognizes sequential and non-sequential linear structural motifs compatible with extended beta-strands and alpha-helices. J. Mol. Biol. 1999, 292 (1), 163-172. 

Buckle et al., 1997), and the strongly binding peptide (Chen and Sigler, 1999). They all bind as an extended chain or /l-hairpin to a groove between two helices, reminiscent of the MHC class I antigen-binding site. All these peptides are unstructured in solution, but adopt the extended conformation when bound to the apical domain. 

Fig. 18.4. a Schematic representations of selected helical parameters, characterizing the relative positions and orientations of bases within base pairs. From top Shear, buckle and propeller twist, b Schematic representations of selected helical parameters, characterizing the relative positions and orientations of base pairs. From top Displacement, roll and helical twist... 

Other artificial muscle applications have been demonstrated as well. Carpi et al. used helical contractile linear actuators and buckling actuators to actuate eyeballs for use in an android face [258, 268, 269]. Another eyeball actuator has been developed by Liu et al. based on their inflated actuator design their actuator is capable of generating eyeball rotations from —50 to 50 [241]. Kombluh et al. have also reported on a mouth driven by a DE actuator [4]. Biddis and Chau have provided a good review on the challenges and opportunities of DE actuators for upper limb prosthetics [270]. 

Fig. 13.17 Probability density distributions of intra base pair helical parameters for 6L and 6 from molecular dynamics simulations (a) buckle, (b) propeller, and (c) opening angles for the 5 tind 3 A-T base pair of the TT step in 6 (blue line and red line) and the 5 and 3 A-T base ptiir of the TT step in 61. (green line and teal line)...

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