The vertebrate hindbrain is transiently segmented during its early development with the formation of reiterated bulges, the rhombomeres (r). The Krox-20 gene, which encodes a zinc finger transcription factor, has been shown previously to be implicated in the maintenance of r3 and r5 (Schneider-Maunoury, S., Topilko, P., Seitanidou, T., Levi, G., Cohen-Tannoudji, M., Pournin, S., Babinet, C. and...

T=x+y+z+3xy+3xz+3xy+ 3xh+ £ « y " V + a^a£. Set y = Xz. Then Î becomes £ == x + r2œV + rgt?£ + • + r6s , r2=:3\ +A\-\-3, rz=D\ +E\ r^3\+F\*+M\+G\+3, r 5 = JBX + „5TX 3 + 2A + f7X, r6 = X 6 + cxX 5 -f . . . + c5X + 1. Now r = x zfc cc» — z, viz., is of type TT, if and only if (21) r a s r 4 s r 5 s 0 , rj s 1, r6 s 1 (mod 7) ; while T is a perfect cube if and only if (22) rB == r5 == 0, r4 == 5r...

Pan African Medical Journal. 2017; 27:205 doi:10.11604/pamj.2017.27.205.13273 This article is available online at: http://www.panafrican-med-journal.com/content/article/27/205/full/ © Amina Kissou et al. The Pan African Medical Journal ISSN 1937-8688. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2....