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Funding for open access publishing: Universidad de Granada/CBUA., The main aim of the present work is to investigate the role of the Maxwell stress tensor in the study of active materials. Despite the importance of this tensor in modeling mechatronic devices used in sophisticated applications, its non-symmetry still generates controversies in the literature, probably because classical continuum mechanics assumes a symmetric Cauchy stress, although the sum of Cauchy and Maxwell stresses is non-symmetric. In the framework of generalised continuum mechanics-a more advanced formalism than the classical one-, each material point has an associated microstructure so that the micro-rotations of the electric/magnetic dipoles present in real active materials may be simulated. To this end, a modified total stress formulation, including an angular momentum balance, is developed and implemented into a finite element research code using a complex-step formulation. It is concluded that generalised mechanics allows for incorporating both symmetric and non-symmetric contributions of the Maxwell tensor. Consequently, the rotations generated by the electromagnetic field may be analysed. The influence of the complete Maxwell tensor in a magnetostrictive actuator is studied by several magneto-mechanical numerical experiments of a Terfenol-D rod encircled by air, and several conclusions are highlighted., Universidad de Granada/CBUA

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MHCY is a candidate region for influencing immune responses in chickens. MHCY contains multiple specialized, polymorphic MHC class I loci along with loci belonging to 4 additional gene families. In this study, MHCY haplotypes were tested for association with cecal colonization after Campylobacter jejuni infection of a backcross [(Line 61 × Line N) × Line N] population derived from 2 White Leghorn research lines, Line 61 and Line N, that were previously shown to exhibit heritable differences in colonization. Samples were obtained for 51 birds challenged with 108 CFU Campylobacter jejuni at 3 wk of age. Viable C. jejuni in the ceca were enumerated 5 d postinfection and counts were log-transformed for analysis. Birds were assigned to either low or high colonization groups based on the individual count being below or above the mean bacterial count for all birds. The mean bacterial count of the low infection group differed significantly from the high infection group. Sex and MHCB haplotype had similar distributions within the 2 groups. Overall, 7 MHCY haplotypes were found to be segregating. Two were significantly associated with C. jejuni colonization. MHCY Y18 was associated with low colonization (P = 3.00 × 10-5); whereas MHCY Y11a was associated with high colonization (P = 0.008). The MHCY haplotype impacted the mean bacterial count among all birds with MHCY Y18 having the lowest bacterial count compared with MHCY Y11a and all other MHCY (Y5, Y7, Y8, Y11b, and Y11c) haplotypes. These findings support further investigation of the contribution of chicken MHCY in resistance to Campylobacter colonization.