The Manche-à-Eau mangrove lagoon, Guadeloupe (16°16'N; 61°33'W), French West Indies, in the life cycle of coastal fish species

International audienceThe functioning of the Manche-à-Eau lagoon and of its mangrove environment with the population of marine fish of Guadeloupe has been studied since 1983, and particularly in the 2000s. This ecosystem supports a stable fish assemblage structure because of its twice a day turnover (14.8%) of marine water. It is a favorable and important site for the reproduction (38%) and growth (46%) of a large number of species. The life cycle of these fish species share, for the most part, an ecophase in the mangrove in brackish water and a marine ecophase outside the lagoon. The mangrove plays a vital role in the retention of continental nutrients. This facilitates the trophic exploitation of vegetal and animal detritus bases by the fish in high population density. The majority of populations present individuals reaching length at least 40% from the known maximum length for the species, although only 38.1% have individuals longer than 300 mm. The mangrove aids in the spawning activity of fish species (41% to 58% of the total abundance) and in the reproductive (maturation, migration) process (58% in density and 70% in biomass). The sedentary species lay their eggs in the mangrove, whereas the temporary species stay there during their trophic ecophase or after a genesic migration from the sea to assure sexual maturation for both sexes in the species

Topological confinement in graphene bilayer quantum rings

We demonstrate the existence of localized electron and hole states in a ring-shaped potential kink in biased bilayer graphene. Within the continuum description, we show that for sharp potential steps the Dirac equation describing carrier states close to the K (or K') point of the first Brillouin zone can be solved analytically for a circular kink/anti-kink dot. The solutions exhibit interfacial states which exhibit Aharonov-Bohm oscillations as functions of the height of the potential step and/or the radius of the ring

Microfenótipos e proteínas associados à expressão da resistência durável à ferrugem da folha do trigo.

Editores técnicos: Joseani Mesquita Antunes, Ana Lídia Variani Bonato, Márcia Barrocas Moreira Pimentel

Efeito do zinco, boro, molibdênio e calagem na produção de soja-perene (Glycine javanica L.) cultivada em solos de cerrado, em condições de casa-de-vegetação.

Este trabalho foi conduzido em casa-de-vegetacao, com amostras de solos do municipio de Sete Lagoas, Estado de Minas Gerais. Foram coletadas amostras de solo: Latossolo Vermelho-Amarelo e Latossolo Vermelho-Escuro, fase cerrado, de 0 a 20 cm de profundidade. Este trabalho teve como objetivo estudar a resposta da soja-perene (Glycine javanica L.) variedade "Tinaroo", a aplicacao de zinco, boro molibdenio e calagem bem como observar a influencia da calagem na disponibilidade de alguns nutrientes. As plantas foram analisadas quanto aos testes totais de nitrogenio, fosforo, potassio, calcio, magnesio, zinco, boro e molibdenio

Time Resolution and Linearity Measurements for a Scintillating Fiber Detector Instrumented with VLPC's

The time resolution for a charged particle detection is reported for a typical scintillating fiber detector instrumented with Rockwell HISTE-IV Visible Light Photon Counters. The resolution measurements are shown to agree with a simple Monte Carlo model, and the model is used to make recomendations for improved performance. In addition, the gain linearity of a sample of VLPC devices was measured. The gain is shown to be linear for incident light intensities which produce up to approximately 600 photoelectrons per event.Comment: 18 pages, 14 figures; Submitted to Nucl. Instr & Meth. in Phys. Res. A; Please direct correspondence to [email protected]

Electronic Correlation and Magnetism in the Ferromagnetic Metal Fe3GeTe2

Motivated by the search for design principles of rare-earth-free strong magnets, we present a study of electronic structure and magnetic properties of the ferromagnetic metal Fe3GeTe2 within local density approximation (LDA) of the density functional theory, and its combination with dynamical mean-field theory (DMFT). For comparison to these calculations, we have measured magnetic and thermodynamic properties as well as X-ray magnetic circular dichroism and the photoemission spectrum of single crystal Fe3GeTe2. We find that the experimentally determined Sommerfeld coefficient is enhanced by an order of magnitude with respect to the LDA value. This enhancement can be partially explained by LDA+DMFT. In addition, the inclusion of dynamical electronic correlation effects provides the experimentally observed magnetic moments, and the spectral density is in better agreement with photoemission data. These results establish the importance of electronic correlations in this ferromagnet.Comment: 6 pages, 5 eps embedded eps figures. Physical Review B, accepted versio