We show that a 1-error-correcting code C is ‘foldable’ over its kernel via the Steiner triple systems associated to the codewords whenever C is perfect. The resulting ‘folding’ produces a graph invariant that for Vasil’ev codes of length 15 is complete, showing in particular that there exist nonadditive propelinear codes and just one nonlinear Vasil’ev additive code up to equivalence.

Soft cellular structures that comprise a solid matrix with a square array of holes open avenues for the design of novel soft and foldable structures. Our results demonstrate that by simply changing the shape of the holes the response of porous structure can be easily tuned and soft structures with optimal compaction can be designed.

Purpose: To evaluate the near visual performance of an accommodative intraocular lens (IOL); Tetraflex, in comparison to a standard monofocal foldable IOL in cataract surgery. Setting: Eye Research Center, Farabi Eye Hospital, Department of Ophthalmology, Tehran University of Medical Sciences, Iran. Methods: Forty six eyes of 23 patients with cataract underwent phacoemulsification and accommoda...

OBJECTIVE To evaluate efficiency, predictability, stability, complications, and patient satisfaction after implantation of a foldable iris-fixated phakic intraocular lens (PIOL) for the correction of myopia. DESIGN Prospective, nonrandomized, comparative (self-controlled) trial. PARTICIPANTS Forty-one eyes of 22 myopic patients aged 18 to 56 years (mean, 36 years) with average sphere of -8....