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• Multiferroic Ca 3 Mn 2 O 7 thin films were prepared by laser ablation on SrTiO 3 substrates. • The conditions for the stabilization of the Ca 3 Mn 2 O 7 phase were determined. • Presence of A2 1 am ferroelectric phase and substrate-induced polar distortion enhancement. • Magnetoelectric and magnetically induced dipolar correlations observed in the samples. • Substrate-induced strain favours multiferroicity in Ca 3 Mn 2 O 7 films. Multiferroic Ruddlesden-Popper Ca 3 Mn 2 O 7 thin films were prepared by laser ablation on SrTiO 3 substrates. For low laser fluences and high oxygen pressures, the films assumed the CaMnO 3 Pnma orthorhombic structure. However, by increasing fluence and decreasing the oxygen pressure, the Ca 3 Mn 2 O 7 phase is achieved through a post-deposition annealing treatment. Furthermore, the ferroelectric phase A2 1 am was observed in the films, along with the orthorhombic Acaa phase, with a preferential [111] growth orientation and substrate-induced enhancement of the polar ferroelectric distortion. The dielectric permittivity shows dispersion described by the Havriliak-Negami function, and from fits to the curves, a different behavior was observed in the antiferromagnetic region. Also, the Kohlrausch-Williams-Watts stretched exponential parameter showed an abrupt decrease below ∼110 K, near the Néel temperature. This indicates the presence of magnetoelectric interactions and magnetically induced enhancement of dipolar correlations in the samples, favoring substrate-induced strain to enhance multiferroicity in these films. [Display omitted] [ABSTRACT FROM AUTHOR]

Phospholipases are esterases involved in lipid catabolism. In pathogenic micro-organisms (bacteria, fungi, parasites) they often play a critical role in virulence and pathogenicity. A few phospholipases (PL) have been characterised so far at the gene and protein level in unicellular parasites including African trypanosomes (AT). They could play a role in different processes such as host–pathogen interaction, antigenic variation, intermediary metabolism. By mining the genome database of AT we found putative new phospholipase candidate genes and here we provided biochemical evidence that one of these has lipolytic activity. This protein has a unique non-canonical glycosome targeting signal responsible for its dual localisation in the cytosol and the peroxisomes-related organelles named glycosomes. We also show that this new phospholipase is excreted by these pathogens and that antibodies directed against this protein are generated during an experimental infection with T. brucei gambiense, a subspecies responsible for infection in humans. This feature makes this protein a possible tool for diagnosis. [ABSTRACT FROM AUTHOR]

Abstract The Eastern Marlim oilfield, located in the northeastern offshore of the Campos Basin, is a portion of the Marlim Complex, one of the most important oil accumulations ever found in Brazil. This paper presents findings from lithofacies, sequence stratigraphy and petrophysical analyses for the Oligocene-Miocene section of the Eastern Marlim oilfield. Here, we evaluate at least four main lithofacies associations and three major zones recognized in the latter section, presenting sedimentological and stratigraphical interpretations based on stratigraphic correlations, distribution and sand proportion maps, and accompanying petrophysical analysis. Our findings suggest at least two bipartite turbiditic flows representing different stages of deposition associated with a deep-water turbidite sequence, composing the elements of a submarine lobe complex. Massive unconsolidated amalgamated sandstone bodies, displaying very good porosity, lateral and vertical continuity, reflecting excellent reservoirs. The final depositional model of the studied Oligocene-Miocene interval in this work is part of the first-order Highstand System Tract (HST) of the Campos Basin, which in turn represents a second-order, exploration-scale depositional sequence. Finally, the sequence stratigraphic model of the Oligocene-Miocene section of the Eastern Marlim oilfield has an architecture similar to those that have been developed from Oligocene-Miocene global sea level changes. Highlights • A lithofacies, sequence stratigraphic and petrophysical evaluation is proposed for the Eastern Marlim oilfield. • Four main lithofacies and three major zones were recognized. • Two-bipartite turbiditic flows represent different stages of deposition. • A deep-water submarine lobe complex was identified. • The studied section represent a first order HST and a second order depositional sequence. [ABSTRACT FROM AUTHOR]