Characterization of a high strain composite material

L'Garde has designed and developed a high-strain composite material consisting of car- bon FIbers embedded in a silicone matrix. The behavior of this material is significantly different from standard composites and the paper presents special test methods to measure the properties of this material. It is found that rule of mixtures estimates are quite accurate for the longitudinal moduli in tension and bending, but less accurate for compression. The Poisson's ratio prediction is also not accurate. Regarding the strength of the composite, it is found that conservative predictions of tensile and compressive strengths can be obtained respectively from the Weibull distribution of the strength of a single fiber combined with a simple bundle theory, and the elastic fiber microbuckling stress

Cathodal transcranial direct current stimulation over the right dorsolateral prefrontal cortex cancels out the cost of selective retrieval on subsequent analogical reasoning

Analogical reasoning involves mapping the relation between two concepts within a specific field into a new domain to selectively retrieve a possible solution. Neuroimaging studies have shown that both selective retrieval and reasoning by analogy are related to activity in prefrontal regions such as the dorsolateral prefrontal cortex (DLPFC). In the present study, we investigate the role of the right DLPFC in modulating memory accessibility and its impact on analogical reasoning by using transcranial direct current stimulation (tDCS). Participants performed a four-term reasoning task after performing repeated selective retrieval of previously presented items, some of which could be used as solutions in the analogical test. During selective retrieval, half of the participants received cathodal tDCS over the right DLPFC and the other half received sham stimulation. The results reveal that whereas the sham group showed the expected cost in performance that is associated with selective retrieval, the cathodal group did not exhibit such an impairment in reasoning. No general effects of tDCS on analogical performance were observed. Altogether, our results support the involvement of the right DLPFC as a core component of a control network that selectively contributes to the retrieval component of analogical reasoning, but with little role in mapping relations between different domains.This work was supported by the Spanish Ministry of Education and Science and Ministry of Economy, Industry and Competitiveness grants FPU014/07066 to TMV, PSI2015-65502-C2-1-P and PGC2018-093786-B-I00 to TB, and PSI2015-65502-C2-2-P to CJGA

The relative role of executive control and personality traits in grit

Although grit is predictive of wellbeing, educational achievement, and success in life, it has been conceptualized as largely distinct from cognitive ability. The present study investigated the link between grit and executive functions since regulation abilities might underlie the expression of grit. A hundred thirty-four people were administered personality questionnaires (grit, impulsiveness, and mindfulness) and four experimental tasks tapping into Miyake’s and Braver’s models of executive functioning (including measures of flexibility, inhibition, working memory, and control mode dimensions). Multivariate analyses showed that two composite scores (trait and executive functioning) were reliably predictive of grit, although it was the trait composite (characterized by low impulsivity and high mindfulness) that explained more variance. Importantly, gritty participants did not demonstrate enhanced executive functioning. Instead, they exhibited a different pattern of performance that might be reflecting a cautious profile of control, characterized by paying attention to all available information, less reliance on previous contextual cues but sensitive to conflicting information of the current context. These findings converge with Duckworth’s idea that high grit people do not necessarily have a greater cognitive capacity. Rather, they use it in a different way.This work was supported by the Spanish Ministry of Economy and Competitiveness and the Andalusian Government (Fondos FEDER) grants: doctoral research Grant ES-2016-078667 to NA; PSI2015-65502-C2-1-P, A.CTS.111.UGR18 and PGC2018-093786-B-I00 to TB; and PSI2015- 65502-C2-2-P to CG-A. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

Electrophysiological correlates of interference control at retrieval predict performance on a subsequent analogical reasoning task

Previous research has shown that variations in the accessibility of relevant information that stem from retrieval practice may impair analogical reasoning. In the present study, we sought to examine the neural signatures of inhibitory control during selective retrieval and its effects on a subsequent analogical reasoning task by employing electrophysiological measures. At a behavioral level, we found that selective retrieval of a subset of potential solutions led to impaired performance on the analogy test. ERPs analyses during selective retrieval revealed that (1) the repeated presentation of retrieval cues was associated with decreased amplitudes for the FN400 ERP effect, possibly reflecting reduced reactivation of competitor associates and interference across retrieval attempts; (2) this effect correlated positively with the retrieval-related impairment in analogical reasoning performance. During the analogy test, the production of control solutions (non-affected by prior retrieval practice) was characterized by more positive modulations of anterior frontal and parietal ERPs than the production of unstudied solutions, whereas inhibited solutions elicited similar amplitudes to unstudied solutions. This effect was restricted to the retrieval phase of the analogy where the actual solutions had to be retrieved, but it did not affect the mapping phase where the accessibility status of the possible solutions failed to reveal significant amplitude differences. These findings suggest that control during selective retrieval may lead to the downregulation of competing memory representations and advance our understanding of the neural correlates of analogical thinking.This work was supported by the Spanish Ministry of Education and Science, Ministry of Economy, Industry and Competitiveness and the Andalusian Government (Fondos FEDER) grants: FPU014/07066 to TMV, PSI2015-65502-C2-1-P, A.CTS.111.UGR18 and PGC2018-093786-B-I00 to TB, and PSI2015-65502-C2-2-P to CJGA. Thanks to Borja Molina for his technical support and the two reviewers for their helpful feedback and comments on a previous version of this manuscript

Selective voluntary forgetting in young and older adults

Aging is thought to involve a decline in executive-control capacities, although evidence regarding this claim is not always clear. Thus, although studies exist that suggest impoverished inhibitory memory control in older adults relative to younger adults, experiments with the list-method direct forgetting procedure have mostly failed to show adult-age differences in voluntary forgetting. In the present study we aimed to further study this issue by comparing young-old and young adults’ performance with the selective directed forgetting (SDF) procedure, which we assumed to involve higher demands of executive control than the standard nonselective procedure. Thus, on the basis of previous studies showing that a critical factor in finding adult-age differences in executive-control tasks is the overall challenge posed by the tasks, we predicted less SDF in older adults than in younger adults. Supporting our hypothesis, across three experiments we show evidence of older adults’ impoverished capacity to voluntarily forget episodic memories, although only when the task requires selective forgetting. Ours join other findings to suggest that sensitiveness to detect adult-age differences in cognitive control may strongly depend on the executive-control demands imposed by tasks

Software architecture for customized physical exercise prescription

En la actualidad existe una gran cantidad de aplicaciones para la realización de ejercicio físico. En este artículo se presenta una arquitectura software para una aplicación que permite la prescripción de ejercicios físicos personalizados. Esta arquitectura incluye dos funcionalidades, la funcionalidad para el especialista que prescribe el ejercicio y la funcionalidad para el usuario que debe seguir esta prescripción. La interacción entre el especialista y el usuario se realiza mediante el envío de eventos. Especialistas (médicos/fisioterapeutas/educadores físicos) pueden indicar los ejercicios adecuados en cada caso. Esta aplicación permitirá a los usuarios con demanda de atención personalizada mejorar la condición física y la calidad de vida. Los usuarios podrán realizar el ejercicio físico de forma autónoma, sin tener que realizar desplazamientos y en un horario flexibleCurrently there is a lot of available applications to do physical exercise. This article describes the software architecture for an application that allows customized exercise prescription. This architecture includes two functionalities, the functionality that allows specialists to prescribe physical exercises and the functionality for users who must follow this prescription. Interactions between specialists and users are allowed by means of sending events. Specialists (doctors, physiotherapists and physical educators) can indicate appropriate exercises in each case. This application will allow users with demand for personalized attention to improve their fitness and quality of life. Users can perform physical exercise autonomously, without having to travel and in a flexible schedul