Precision grips

Baker, S. N., Spinks, R., Jackson, A., and Lemon, R. N. (2001). Synchronization in monkey cortex during a precision grip task. I. Task-dependent modulation in single-unit synchrony. J. Neurophysiol. 85, 869-885. 

Use power grip where power is needed and precision grip for precise tasks. 

Three-point chuck Precision grip with digits 1,2, and 3 (thumb set to oppose the midhne between digits 2 and 3) digits 4 and 5 give additional support... 

Two-point grip Precision grip with digits 1 and 2 (thumb set to oppose forefinger) digits 3,4, and 5 fully flexed and not used or fully extended... 

V. Grinyagin, E. V. Biryukova, and M. A. Maier, Kinematic and dynamic synergies of human precision-grip movements, Journal of Neurophysiology, vol. 94, pp. 2284-2294,2005. 

A leucine zipper is a structural motif present in a large class of transcription factors. These dimeric proteins contain two extended alpha helices that grip the DNA molecule much like a pair of scissors at adjacent major grooves. The coiled-coil dimerization domain contains precisely spaced leucine residues which are required for the interaction of the two monomers. Some DNA-binding proteins with this general motif contain other hydrophobic amino acids in these positions hence, this structural motif is generally called a basic zipper. 

The handles and grips should be cylindrical or oval with a diameter of 3.0-4.5 cm (for precise operations the recommended diameter is 0.5-1.2 cm). 

The use of 0.05% strain as the lower limit for determining modulus is a very stringent requirement and needs an extensometer accurate to at least I micrometer. There arc also implications for the test piece in terms of flatness or warping and for the precision of the gripping mechanism which, frankly, are unrealistic in some cases. It may be that some of these points will be addressed at the next revision of the standard. 

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