Nucleotides and free amino acids in sea urchin Paracentrotus lividus gonads: Contributions for freshness and overall taste.

This study aims to report the chemical changes, specifically the nucleotides and free amino acids (FAAs) during refrigerated storage of live sea urchin Paracentrotus lividus (7 °C) and packed gonads (2 °C) and respective contributions to overall taste. Results showed that the adenylate energy charge (AEC) is an adequate indicator for live sea urchin through storage, while K-value does not distinguish freshness. Changes of both indexes were not clear in packed gonads. The FAAs profile were related with maturation stage where amino acids associated to sweet (Gly, Ala), umami (Glu) and bitter (Arg, Lys, His, Val) had significant contribution to overall taste. In general, the storage did not significantly affect the FAAs content nor its contribution to overall taste in contrast to nucleotides that seemed to induce potential changes after day 5. The findings provide insights that will complement a full study on quality index scheme development of the products.

Semi-industrial development of nutritious and healthy seafood dishes from sustainable species.

This study aimed to devise innovative, tailor-made, appealing, tasty and semi-industrialized dishes, using sustainable and under-utilized seafood species (bib, common dab, common carp, blue mussel and blue whiting), that can meet the specific nutritional and functional needs of children (8-10-years), pregnant women (20-40-years) and seniors (≥60-years). Hence, contests were organised among cooking schools from 6 European countries and the best recipes/dishes were reformulated, semi-industrially produced and chemically and microbiologically evaluated. The dishes intended for: (i) children and pregnant women had EPA + DHA and I levels that reached the target quantities, supporting the claim as "high in I"; and (ii) seniors were "high in protein" (24.8%-Soup_S and 34.0%-Balls_S of the energy was provided by proteins), "high in vitamin B12", and had Na contents (≤0.4%) below the defined limit. All dishes reached the vitamin D target value. Sausages_C, Roulade_P, Fillet_P and Balls_S had a well-balanced protein/fat ratio. Roulade_P presented the highest n-3 PUFA/n-6 PUFA ratio (3.3), while Sausages_C the lowest SFA/UNS ratio (0.2). Dishes were considered safe based on different parameters (e.g. Hg-T, PBDEs, Escherichia coli). All represent dietary sources contributing to meet the reference intakes of target nutrients (33->100%), providing valuable options to overcome nutritional and functional imbalances of the three groups.

Strategies to reduce sodium levels in European seabass sausages.

Considering the increasing demand towards "ready-to-cook" processed seafood products, recognised as being potential contributors to high sodium (Na) intake by consumers, this study aimed to assess the effect of sodium chloride (NaCl) reduction on physicochemical, microbiological and sensory properties of European seabass (Dicentrarchus labrax) sausages stored in chilling conditions during 5 weeks. Three formulations were tested in comparison with a control (100% NaCl, CTR): (i) 50% NaCl+50% ME (oleoresins microcapsules) (F1); (ii) 50% NaCl+50% KCl (F2); and (iii) only 50% NaCl (F3). The NaCl reduction mainly affected the texture and the salty taste, resulting in softer and perceived as less salty sausages after processing. However, hardness differences disappeared after 5 weeks. It seems that an antioxidant protection was obtained in sausages formulated with oleoresins microcapsules. No or low growth of psychrotrophic and mesophilic bacteria was observed (≤2.40 log CFU/g). Decreasing NaCl content and/or partially replacing it (50%) by KCl or oleoresins microcapsules seem to be suitable solutions to reduce Na (30.9-36.3%) levels, while maintaining the chilled sausages quality for 5 weeks. The partial replacement of NaCl by KCl also allows obtaining a product richer in K (997.2 mg/100 g), which ingestion may contribute for a cardiovascular protective effect.

Efeitos de um marcador temporal sobre respostas de escolha por maior atraso e magnitude do reforço em crianças / Effects of a time marker on responses of choice for further delay and magnitude of reinforcement in children / Los efectos de un contador de tiempo sobre las respuestas de elección por más retraso y magnitud del reforzamiento en niños

ResumoO presente experimento verificou se a apresentação de um marcador temporal durante o período de atraso do reforço aumentaria as respostas no componente com maior magnitude e atraso do reforço (autocontrole), diminuindo as escolhas pelo componente de menor atraso e magnitude (impulsividade), em um esquema concorrente. Três valores de atraso do reforço foram investigados. Participaram nove crianças distribuídas em três condições manipuladas no período de atraso do reforço: relógio, não-relógio e blackout. Escolhas entre o componente de autocontrole e impulsividade ocorriam na tela de computador sendo consequencia dos pontos trocados por brindes. Encontrou-se autocontrole na primeira apresentação dos menores valores de atraso no componente de maior atraso, mas não com valores maiores, independentemente da condição em vigor. O marcador temporal não indicou ser uma condição que aumente as respostas de autocontrole. Tais respostas estiveram relacionadas aos valores do atraso.(AU)

AbstractThis experiment aimed to determine whether the presentation of a temporal marker during the delay of reinforcement would increase choice response related to the greater magnitude and delay of reinforcement component (self-control), reducing the choices of the shorter delay and small magnitude component (impulsivity). Three values of delay interval have been investigated. Nine children were assigned to three conditions manipulated in the delay period: clock, no clock and blackout. Choices between self-control and impulsiveness component occurred on the computer screen producing points exchanged for gifts. Self-control was found in the first presentation of the smaller lag values in longer delay component, but not to larger values, regardless of the condition in effect. The time counter has not indicated to be a condition that increases the self-control. Such responses were related to the delay values.(AU)

ResumenEl presente experimento evaluó si la presentación de un contador de tiempo en el período de retraso del reforzamiento aumenta las respuestas del componente con más magnitud y retraso del reforzamiento (auto-control), reducindo la elección del componente con menos retraso y magnitud (impulsividad), en una esquema competidor. Tres tipos de retraso del reforzamiento han sido investigados. Participaron nueve niños asignados en tres condiciones manejadas en el periodo de retraso de refuerzo: con reloj, sin reloj y blackout. Las elecciones entre el componente de autocontrol y impulsividad ocurrieron en la pantalla del ordenador consequenciadas por puntos cambiados después por regalos. Se ha encuentrado auto-control en la primera presentación de los tipos más pequeños de retraso en el componente con más magnitud y retraso del reforzamiento, pero el mismo no ha pasado con los tipos de retrasos más largos, independientemente de la condición en efecto. El contador de tiempo no ha indicado ser una condición de incremento de las respuestas de auto-control. Tales respuestas solo se han relacionado con los tipo de retraso.(AU)

Efeitos de um marcador temporal sobre respostas de escolha por maior atraso e magnitude do reforço em crianças / Effects of a time marker on responses of choice for further delay and magnitude of reinforcement in children / Los efectos de un contador de tiempo sobre las respuestas de elección por más retraso y magnitud del reforzamiento en niños

O presente experimento verificou se a apresentação de um marcador temporal durante o período de atraso do reforço aumentaria as respostas no componente com maior magnitude e atraso do reforço (autocontrole), diminuindo as escolhas pelo componente de menor atraso e magnitude (impulsividade), em um esquema concorrente. Três valores de atraso do reforço foram investigados. Participaram nove crianças distribuídas em três condições manipuladas no período de atraso do reforço: relógio, não-relógio e blackout. Escolhas entre o componente de autocontrole e impulsividade ocorriam na tela de computador sendo consequencia dos pontos trocados por brindes. Encontrou-se autocontrole na primeira apresentação dos menores valores de atraso no componente de maior atraso, mas não com valores maiores, independentemente da condição em vigor. O marcador temporal não indicou ser uma condição que aumente as respostas de autocontrole. Tais respostas estiveram relacionadas aos valores do atraso.

This experiment aimed to determine whether the presentation of a temporal marker during the delay of reinforcement would increase choice response related to the greater magnitude and delay of reinforcement component (self-control), reducing the choices of the shorter delay and small magnitude component (impulsivity). Three values of delay interval have been investigated. Nine children were assigned to three conditions manipulated in the delay period: clock, no clock and blackout. Choices between self-control and impulsiveness component occurred on the computer screen producing points exchanged for gifts. Self-control was found in the first presentation of the smaller lag values in longer delay component, but not to larger values, regardless of the condition in effect. The time counter has not indicated to be a condition that increases the self-control. Such responses were related to the delay values.

El presente experimento evaluó si la presentación de un contador de tiempo en el período de retraso del reforzamiento aumenta las respuestas del componente con más magnitud y retraso del reforzamiento (auto-control), reducindo la elección del componente con menos retraso y magnitud (impulsividad), en una esquema competidor. Tres tipos de retraso del reforzamiento han sido investigados. Participaron nueve niños asignados en tres condiciones manejadas en el periodo de retraso de refuerzo: con reloj, sin reloj y blackout. Las elecciones entre el componente de autocontrol y impulsividad ocurrieron en la pantalla del ordenador consequenciadas por puntos cambiados después por regalos. Se ha encuentrado auto-control en la primera presentación de los tipos más pequeños de retraso en el componente con más magnitud y retraso del reforzamiento, pero el mismo no ha pasado con los tipos de retrasos más largos, independientemente de la condición en efecto. El contador de tiempo no ha indicado ser una condición de incremento de las respuestas de auto-control. Tales respuestas solo se han relacionado con los tipo de retraso.

Electromechanical coupling and temperature-dependent polarization reversal in piezoelectric ceramics.

Electrostriction plays a central role in describing the electromechanical properties of ferroelectric materials, including widely used piezoelectric ceramics. The piezoelectric properties are closely related to the underlying electrostriction. Small-field piezoelectric properties can be described as electrostriction offset by the remanent polarization which characterizes the ferroelectric state. Indeed, even large-field piezoelectric effects are accurately accounted for by quadratic electrostriction. However, the electromechanical properties deviate from this simple electrostrictive description at electric fields near the coercive field. This is particularly important for actuator applications, for which very high electromechanical coupling can be obtained in this region. This paper presents the results of an experimental study of electromechanical coupling in piezoelectric ceramics at electric field strengths close to the coercive field, and the effects of temperature on electromechanical processes during polarization reversal. The roles of intrinsic ferroelectric strain coupling and extrinsic domain processes and their temperature dependence in determining the electromechanical response are discussed.