230 research outputs found

    Sharing delay costs in stochastic scheduling problems with delays

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    An important problem in project management is determining ways to distribute amongst activities the costs that are incurred when a project is delayed because some activities end later than expected. In this study, we address this problem in stochastic projects, where the durations of activities are unknown but their corresponding probability distributions are known. We propose and characterise an allocation rule based on the Shapley value, illustrate its behaviour by using examples, and analyse features of its calculation for large problems

    Cambios de compuestos volátiles extraídos por SPME en jamones Ibéricos durante la curación.

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    A headspace SPME procedure was tested to study the evolution of volatile compounds during the ripening of Iberian hams from pigs reared in a Montanera system (outdoorbased, with acorn and pasture available) and a HO-Pienso system (indoor-based, with a high oleic acid concentrate). The effect of the ripening time on volatile compounds was more marked than the effect of feeding system. Most volatile compounds affected by the ripening time were compounds that come from Strecker and Maillard reactions, which increased significantly (Un procedimiento de microextración en fase sólida (SPME) en espacio de cabeza fue ensayado para estudiar la evolución de los compuestos volátiles durante la curación de Jamones Ibéricos de cerdos criados en régimen de montanera (en libertad, con bellotas y pasto disponible) y un sistema OH-Pienso (estabulados, con un pienso alto en ácido oléico). El efecto del tiempo de curación en los compuestos volátiles fue más marcado que el efecto de la alimentación. La mayoría de los compuestos volátiles afectados por el tiempo de curación fueron compuestos que proceden de la reacción de Strecker y Maillard, que se incrementaron significativamente (p < 0.05) durante el tiempo de curación. Esta tendencia fue clara para los compuestos volátiles: 2-metilpropanal, 2-metilbutanal, 2-metil-1-butanol, disulfuro de dimetilo, 2,6.dimetilpiracina + dihidro-2(3H)furanona y bencenometanol y, por tanto ellos podrían ser usados como indicadores del tiempo de maduración. Por el contrario, algunos compuestos derivados de la oxidación lipídica disminuyeron significativamente durante el procesado del jamón. El sistema de alimentación tuvo un ligero efecto en los compuestos volátiles, aunque fue significativo para algunos compuestos (p < 0.05). Algunos de ellos (ácido butanoico, 2,6- dimetilpiracina y 1-octen-3-ol) fueron más abundantes en jamones de Montanera que en jamones de Pienso. Estas pequeñas diferencias podrían ser importantes porque los compuestos involucrados han sido identificados como aromas del jamón Ibérico

    Restrained Eating Is Associated with Lower Cortical Thickness in the Inferior Frontal Gyrus in Adolescents

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    Some eating patterns, such as restrained eating and uncontrolled eating, are risk factors for eating disorders. However, it is not yet clear whether they are associated with neurocognitive differences. In the current study, we analyzed whether eating patterns can be used to classify participants into meaningful clusters, and we examined whether there are neurocognitive differences between the clusters. Adolescents (n = 108; 12 to 17 years old) and adults (n = 175, 18 to 40 years old) completed the Three Factor Eating Questionnaire, which was used to classify participants according to their eating profile using k means clustering. Participants also completed personality questionnaires and a neuropsychological examination. A subsample of participants underwent a brain MRI acquisition. In both samples, we obtained a cluster characterized by high uncontrolled eating patterns, a cluster with high scores in restrictive eating, and a cluster with low scores in problematic eating behaviors. The clusters were equivalent with regards to personality and performance in executive functions. In adolescents, the cluster with high restrictive eating showed lower cortical thickness in the inferior frontal gyrus compared to the other two clusters. We hypothesize that this difference in cortical thickness represents an adaptive neural mechanism that facilitates inhibition processes

    Structure and function of the alfa-rhizobia non-coding transcriptome investigated by RNAseq

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    Conferencia presentada en: I Spanish-Portuguese Congress on Beneficial Plant-Microbe Interactions (BeMiPlant) and XVIII National Meeting of the Spanish Society of Nitrogen Fixation (XVIII SEFIN). Oeiras, Portugal, 17-19 octubre (2022)This work was supported by grants BFU2017-82645-P and PID2020-114782GB-I00 funded by MCIN/AEI/10.13039/501100011033 and by “ERDF A way of making Europe” (BFU2017-82645-P), and grant P20_00185 funded by Junta de Andalucía PAIDI/FEDER/EU, awarded to J.I.J.-Z., and by grant US-1250546 funded by FEDER/Universidad de Sevilla to J.M.V

    Allostatic load and executive functions in overweight adults

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    Background/objective: Overweight is linked to inflammatory and neuroendocrine responses potentially prompting deregulations in biological systems harmful to the brain, particularly to the prefrontal cortex. This structure is crucial for executive performance, ultimately supervising behaviour. Thus, in the present work, we aimed to test the relationship between allostatic load increase, a surrogate of chronic physiological stress, and core executive functions, such as cognitive flexibility, inhibitory control, and working memory. Method Forty-seven healthy-weight and 56 overweight volunteers aged from 21 to 40 underwent medical and neuropsychological examination. Results: Overweight subjects exhibited a greater allostatic load index than healthy-weight individuals. Moreover, the allostatic load index was negatively related to inhibitory control. When separated, the link between allostatic load index and cognitive flexibility was more marked in the overweight group. Conclusions: An overweight status was linked to chronic physiological stress. The inverse relationship between the allostatic load index and cognitive flexibility proved stronger in this group. Set-shifting alterations could sustain rigid-like behaviours and attitudes towards food
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