The Shared Reward Dilemma

One of the most direct human mechanisms of promoting cooperation is rewarding it. We study the effect of sharing a reward among cooperators in the most stringent form of social dilemma, namely the Prisoner's Dilemma. Specifically, for a group of players that collect payoffs by playing a pairwise Prisoner's Dilemma game with their partners, we consider an external entity that distributes a fixed reward equally among all cooperators. Thus, individuals confront a new dilemma: on the one hand, they may be inclined to choose the shared reward despite the possibility of being exploited by defectors; on the other hand, if too many players do that, cooperators will obtain a poor reward and defectors will outperform them. By appropriately tuning the amount to be shared a vast variety of scenarios arises, including traditional ones in the study of cooperation as well as more complex situations where unexpected behavior can occur. We provide a complete classification of the equilibria of the $n$-player game as well as of its evolutionary dynamics.Comment: Major rewriting, new appendix, new figure

Emergence and resilience of cooperation in the spatial Prisoner's Dilemma via a reward mechanism

We study the problem of the emergence of cooperation in the spatial Prisoner's Dilemma. The pioneering work by Nowak and May showed that large initial populations of cooperators can survive and sustain cooperation in a square lattice with imitate-the-best evolutionary dynamics. We revisit this problem in a cost-benefit formulation suitable for a number of biological applications. We show that if a fixed-amount reward is established for cooperators to share, a single cooperator can invade a population of defectors and form structures that are resilient to re-invasion even if the reward mechanism is turned off. We discuss analytically the case of the invasion by a single cooperator and present agent-based simulations for small initial fractions of cooperators. Large cooperation levels, in the sustainability range, are found. In the conclusions we discuss possible applications of this model as well as its connections with other mechanisms proposed to promote the emergence of cooperation

Rewarding cooperation in social dilemmas

One of the most direct human mechanisms of promoting cooperation is rewarding it. We study the effect of sharing a reward among cooperators in the most stringent form of social dilemma. Thus, individuals confront a new dilemma: on the one hand, they may be inclined to choose the shared reward despite the possibility of being exploited by defectors; on the other hand, if too many players do that, cooperators will obtain a poor reward and defectors will outperform them. By appropriately tuning the amount to be shared we can cast a vast variety of scenarios, including traditional ones in the study of cooperation as well as more complex situations where unexpected behavior can occur. We provide a complete classification of the equilibria of the nplayer game as well as of the evolutionary dynamics. Beyond, we extend our analysis to a general class of public good games where competition among individuals with the same strategy exists.

A class of Hamilton-Jacobi equations on Banach-Finsler manifolds

The concept of subdifferentiability is studied in the context of $C^1$ Finsler manifolds (modeled on a Banach space with a Lipschitz $C^1$ bump function). A class of Hamilton-Jacobi equations defined on $C^1$ Finsler manifolds is studied and several results related to the existence and uniqueness of viscosity solutions are obtained.Comment: 24 page

Network perspective of histamine related diseases

Histamine is the most pleiotropic biogenic amine. Produced and stored by a limited set of cells—histaminergic neurons, enterochromaffin-like cells, and mast cells—it broadcasts intercellular communication signals to a wide variety of cell types through its tissue-specific receptors. The many molecular interactions of these receptors and other mediators result in complex cellular networks whose alteration result in disease. Therefore, complex diseases map to modules of these cellular networks in the diseasomes. In this communication, we survey the histamine cellular networks to map the histamine diseasome, presenting a network view of the pleiotropy of histamine and its role in several complex diseases.A.A. Moya is a CIBERER fellow. The "CIBER de Enfermedades Raras" is an initiative from the ISCIII (Spain)]. This communication has the support of a travel grant "Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech"

Implementation of a moving finite element mesh within the catenary-pantograph dynamic interaction

En este artículo se presenta la aplicación tecnológica a la interacción dinámica catenaria-pantógrafo de una metodología propuesta para estructuras flexibles sometidas a cargas móviles. En primer lugar se describe el modelado de una malla móvil de elementos finitos que se desplaza sobre el hilo de contacto de forma solidaria al pantógrafo que recorre la catenaria y, posteriormente, se presenta la comparación de esta metodología frente a un modelo de elementos finitos convencional de malla fija. El caso simulado corresponde al propuesto por la norma EN-50318, obteniendo resultados acordes a los intervalos de validación propuestos por dicha norma. La principal ventaja del método de malla móvil reside en que para precisiones análogas el tiempo de cálculo es del orden de 4 veces menor que el modelo clásico.This paper presents a technological application of a general methodology to analyze cable structures under moving loads, particularly on the catenary-pantograph dynamic interaction. This work firstly describes the modeling of a finite element moving mesh which integrally moves over the contact wire following the pantograph along the whole catenary, prior focusing on its comparison against the classical finite element mesh. The case study corresponds to the standard EN-50318 one, whose results fulfill the ranges proposed by this validation rule. The main advantage of the moving mesh method is presented in the falling of computational costs about 4 times lower than the classic model with similar precision.Peer Reviewe