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Larsen K.,CIIMAR - Interdisciplinary Center of Marine and Environmental | Araujo-Silva C.L.,CAPES Foundation

A restricted phylogenetic analysis is conducted to test if the family Akanthophoreidae is monophyletic. The family was found to be monophyletic with a Bremer support of 11 and is redefined to include the genera Akanthophoreus, Chauliopleona, Mimicarhaphura, Parakanthophoreus gen. nov., Paraleptognathia, Stenotanais, and Tumidochelia, while Gejavis is removed. Akanthophoreus and Paraleptognathia are redefined and now consist of only four and two species respectively. The remaining species previously assigned to these genera are transferred to a new genus Parakanthophoreus. A key to the genera of the family is presented. Two new species of Chauliopleona, C. ciimari and C. andeepi, and one of Parakanthophoreus, P. greenwichius, are described from the ANDEEP I-III and ANDEEP-SYSTCO material. Copyright © 2014 Magnolia Press. Source

Goulart E.,CAPES Foundation | Goulart E.,University of Cambridge
Physical Review D - Particles, Fields, Gravitation and Cosmology

It is shown that the causal structure associated to stringlike solutions of the Faddeev-Niemi model is described by an effective metric. Remarkably, the surfaces characterizing the causal replacement depend on the energy momentum tensor of the background soliton and carry implicitly a topological invariant π3(S2). As a consequence, it follows that the preimage curves in R3 nontrivially define directions where the cones remain unchanged. We expect that these early results may be of importance in understanding time dependent solutions (collisions/scatterings) numerically or analytically. © 2015 American Physical Society. Source

Baptista F.G.,CAPES Foundation | Filho J.V.,Sao Paulo State University | Inman D.J.,Virginia Polytechnic Institute and State University
IEEE Sensors Journal

A theoretical and experimental analysis regarding the correct size of PZT (Lead Zirconate Titanate) transducers used in structural health monitoring (SHM) systems based on the electromechanical impedance (EMI) technique is presented. Tests were carried out on aluminum structures using 5A and 5H PZT patches of various sizes. The results show that the sensitivity of SHM systems for damage detection can be optimized if the transducers are correctly sized according to the proposed procedure. © 2006 IEEE. Source

Miranda D.D.A.,Federal University of Pernambuco | de Carvalho-Souza G.F.,CAPES Foundation
Marine Pollution Bulletin

Yes, we are eating plastic-ingesting fish. A baseline assessment of plastic pellet ingestion by two species of important edible fish caught along the eastern coast of Brazil is described. The rate of plastic ingestion by king mackerel (Scomberomorus cavalla) was quite high (62.5%), followed by the Brazilian sharpnose shark (Rhizoprionodon lalandii, 33%). From 2 to 6 plastic resin pellets were encountered in the stomachs of each fish, with sizes of from 1 to 5 mm, and with colors ranging from clear to white and yellowish. Ecological and health-related implications are discussed and the potential for transferring these materials through the food-chain are addressed. Further research will be needed of other species harvested for human consumption. © 2015. Source

Abalos F.,National University of Cordoba | Carrasco F.,National University of Cordoba | Goulart E.,CAPES Foundation | Reula O.,National University of Cordoba
Physical Review D - Particles, Fields, Gravitation and Cosmology

Nonlinear theories generalizing Maxwell's electromagnetism and arising from a Lagrangian formalism have dispersion relations in which propagation planes factor into null planes corresponding to two effective metrics which depend on the pointwise values of the electromagnetic field. These effective Lorentzian metrics share the null (generically two) directions of the electromagnetic field. We show that the theory is symmetric hyperbolic if and only if the cones these metrics give rise to have a nonempty intersection, namely, that there exist families of symmetrizers in the sense of Geroch [26] which are positive definite for all covectors in the interior of the cones intersection. Thus, for these theories, the initial value problem is well posed. We illustrate the power of this approach with several nonlinear models of physical interest such as Born-Infeld, Gauss-Bonnet, and Euler-Heisenberg. © 2015 American Physical Society. Source

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