Co-evolutionnary network approach to cultural dynamics controlled by intolerance

Starting from Axelrod's model of cultural dissemination, we introduce a rewiring probability, enabling agents to cut the links with their unfriendly neighbors if their cultural similarity is below a tolerance parameter. For low values of tolerance, rewiring promotes the convergence to a frozen monocultural state. However, intermediate tolerance values prevent rewiring once the network is fragmented, resulting in a multicultural society even for values of initial cultural diversity in which the original Axelrod model reaches globalization

Gender differences in cooperation: experimental evidence on high school students

The emergence of cooperation among unrelated human subjects is a long-standing conundrum that has been amply studied both theoretically and experimentally. Within the question, a less explored issue relates to the gender dependence of cooperation, which can be traced back to Darwin, who stated that "women are less selfish but men are more competitive". Indeed, gender has been shown to be relevant in several game theoretical paradigms of social cooperativeness, including prisoner's dilemma, snowdrift and ultimatum/dictator games, but there is no consensus as to which gender is more cooperative. We here contribute to this literature by analyzing the role of gender in a repeated Prisoners' Dilemma played by Spanish high-school students in both a square lattice and a heterogeneous network. While the experiment was conducted to shed light on the influence of networks on the emergence of cooperation, we benefit from the availability of a large dataset of more 1200 participants. We applied different standard econometric techniques to this dataset, including Ordinary Least Squares and Linear Probability models including random effects. All our analyses indicate that being male is negatively associated with the level of cooperation, this association being statistically significant at standard levels. We also obtain a gender difference in the level of cooperation when we control for the unobserved heterogeneity of individuals, which indicates that the gender gap in cooperation favoring female students is present after netting out this effect from other socio-demographics factors not controlled for in the experiment, and from gender differences in risk, social and competitive preferences.This paper has benefited from the funding from the Spanish Ministry of Education and Science (Projects ECO2012-34828, RESINEE and PRODIEVO). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

Effects of trapping site on the spectroscopy of 1P1 excited group 12 metal atoms in rare gas matrices

A molecular dynamics deposition model has been used to simulate the growth of rare gas matrices doped with atoms of the group 12 elements zinc, cadmium and mercury. This study investigates the sites occupied by Zn, Cd and Hg metal atoms when isolated in the solid rare gases. To probe the results, the resonance 1 P 1-1 S 0 transitions of the matrix-isolated metal atoms were calculated and compared with the recorded spectra of the M/RG solids. The theoretical spectroscopy obtained in this work was generated using the molecular dynamics with quantum transitions method. In Ne matrices the metal atoms preferably occupy tetra- and hexa-vacancy sites while in the case of Xe matrices, only the single vacancy site is formed. For Ar and Kr matrices Zn but especially Cd can be trapped in tetra- and hexa-vacancy sites in addition to single-vacancy sites, while Hg atoms show exclusive occupancy in single vacancy sites.Fil: Lara Moreno, M.. Universidad de La Habana; Cuba. Instituto Superior de Tecnologías y Ciencias Aplicadas.; Cuba. Université de Bordeaux; Francia. Centre National de la Recherche Scientifique; FranciaFil: Alvarez Hernández, J.. Universidad de La Habana; Cuba. Instituto Superior de Tecnologías y Ciencias Aplicadas.; Cuba. University of Rochester. Department of Chemistry; Estados UnidosFil: Negrín Yuvero, Lázaro Hassiel. Universidad de La Habana; Cuba. Instituto Superior de Tecnologías y Ciencias Aplicadas.; Cuba. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: McCaffrey, J. G.. National University of Ireland. Maynooth University. Department of Chemistry; IrlandaFil: Rojas Lorenzo, G.. Universidad de La Habana; Cuba. Instituto Superior de Tecnologías y Ciencias Aplicadas.; Cub

Social Network Reciprocity as a Phase Transition in Evolutionary Cooperation

In Evolutionary Dynamics the understanding of cooperative phenomena in natural and social systems has been the subject of intense research during decades. We focus attention here on the so-called "Lattice Reciprocity" mechanisms that enhance evolutionary survival of the cooperative phenotype in the Prisoner's Dilemma game when the population of darwinian replicators interact through a fixed network of social contacts. Exact results on a "Dipole Model" are presented, along with a mean-field analysis as well as results from extensive numerical Monte Carlo simulations. The theoretical framework used is that of standard Statistical Mechanics of macroscopic systems, but with no energy considerations. We illustrate the power of this perspective on social modeling, by consistently interpreting the onset of lattice reciprocity as a thermodynamical phase transition that, moreover, cannot be captured by a purely mean-field approach.Comment: 10 pages. APS styl

La realidad virtual y el análisis científico: De la nube de puntos al documento analítico

[ES] Desde la Topografía hemos estado trabajando en obtener la modelización tridimensional de elementos arqueológicos haciendo uso de los sistemas láser escáner de corto, medio y largo alcance. Hemos efectuado el modelado de piezas arqueológicas para museos, levantamientos de yacimientos para equipos científicos y documentación general de áreas de interés cultural.En este artículo pretendemos exponer cómo habiendo llegado a un punto de vista lleno de escepticismo, en el que se podía pensar que la realidad virtual había encontrado un límite en la representación de la arqueología, se puede iniciar un nuevo camino. Proponemos una búsqueda de nuevos modos y procedimientos de análisis con la información recopilada, en definitiva de nuevos documentos para la interpretación científica de la arqueología que participen en la creación de conocimiento, desde las nubes de puntos adquiridas en campo.En este trabajo exploramos los documentos de análisis que son utilizados actualmente en el proceso de creEste trabajo se desarrolla dentro del proyecto I+D: HAR2008-04118/HIST (Segeda y Celtiberia Septentrional: investigación científica, desarrollo rural sostenible y nuevas tecnologías), financiado por el Ministerio de Educación y Ciencia y los fondos FEDER y el Proyecto PADCAM (El Patrimonio Arqueológico y documental de la Comunidad Autónoma de Madrid: Sistematización, gestión, puesta en valor y difusión desde el ámbito local del marco europeo) financiado por la Consejería de Educación, de la Comunidad de Madrid.Farjas, M.; Moreno, E.; García Lázaro, FJ. (2011). La realidad virtual y el análisis científico: De la nube de puntos al documento analítico. Virtual Archaeology Review. 2(4):139-144. https://doi.org/10.4995/var.2011.4570OJS13914424BARBER (2004). Towards A Standard Specification For Terrestrial Laser Scanning In Cultural. Comisión V, WG V/2 ISPRS Estambul. ISPRS( International Society for Photogrammetry and Remote Sensing). Commission V, WG V/2BRACCI S., FALLETTI F., MATTEINI M., y SCOPIGNO R. (2004). Explorando David: diagnóstico y estado de la conservación. Giunti Press. Italia.DEMIR (2004): Laser Scanning For Terrestrial Photogrammetry, Alternative System Or Combined With Traditional System?. Comisión V, WG V/2 ISPRS Estambul. ISPRS( International Society for Photogrammetry and Remote Sensing). Commission V, WG V/2.FARJAS, M. (Ed.) (2007). El registro en los objetos arqueológicos: Métrica y Divulgación. Spain: Reyferr. ISBN 978-84-611-6456-1FARJAS, M. & GARCÍA-LÁZARO, F. J. (Eds.) (2008). Modelización Tridimensional y Sistemas Láser Escáner. Madrid, Spain: La Ergástula.LIFCHITZ MORALES, Claudia; DE LA ROCHA GÓMEZ, Mercedes (2010). Levantamiento a escala 1/200 mediante láser escáner 3D de la fachada principal del Palacio del Infantado, Guadalajara Proyecto Final de Carrera, no publicado, Universidad Politécnica de Madrid (UPM).LÓPEZ GONZÁLEZ, Jaime (2008). Levantamiento mediante láser escáner 3D de un abrigo paleolítico en el yacimiento de Hellín (Albacete). Proyecto Final de Carrera, no publicado, Universidad Politécnica de Madrid (UPM).VÁZQUEZ PELAEZ, Sergio (2008). Levantamiento mediante Láser Escáner 3D de la zona de Los Zarpazos en el yacimiento arqueológico de Atapuerca (Burgos) Proyecto Final de Carrera, no publicado, Universidad Politécnica de Madrid (UPM).WOLTRING (1995), Smoothong and differentiation techniques applied to 3D data. Champaign, Illinois, USA: Human Kineti

Comparison of thermistor linearization techniques for accurate temperature measurement in phase change materials

Alternate energy technologies are developing rapidly in the recent years. A significant part of this trend is the development of different phase change materials (PCMs). Proper utilization of PCMs requires accurate thermal characterization. There are several methodologies used in this field. This paper stresses the importance of accurate temperature measurements during the implementation of T-history method. Since the temperature sensor size is also important thermistors have been selected as the sensing modality. Two thermistor linearization techniques, one based on Wheatstone bridge and the other based on simple serial-parallel resistor connection, are compared in terms of achievable temperature accuracy through consideration of both, nonlinearity and self-heating errors. Proper calibration was performed before T-history measurement of RT21 (RUBITHERM® GmbH) PCM. Measurement results suggest that the utilization of serial-parallel resistor connection gives better accuracy (less than ±0.1°C) in comparison with the Wheatstone bridge based configuration (up to ±1.5°C)

Contests in two fronts

Within the framework of Game Theory, contests study decision-making in those situations or conflicts when rewards depend on the relative rank between contenders rather than their absolute performance. By relying on the formalism of Tullock success functions, we propose a model where two contenders fight in a conflict on two fronts with different technology levels associated: a front with large resource demand and another with lower resource requirements. The parameter of the success function in each front determines the resource demand level. Furthermore, the redistribution or not of resources after a tie defines two different games. We solve the model analytically through the best-response map dynamics, finding a critical threshold for the ratio of the resources between contenders that determines the Nash Equilibrium basin and, consequently, the peace and fighting regimes. We also perform numerical simulations that corroborate and extend these findings. We hope this study will be of interest to areas as diverse as economic conflicts and geopolitics.Comment: 21 pages, 11 figure

Sustainability indicator for the prevention of potential thermal interferences between groundwater heat pump systems in urban aquifers

The steady increase of geothermal systems using groundwater is compromising the renewability of the geothermal resources in shallow urban aquifers. To ensure sustainability, scientifically-based criteria are required to prevent potential thermal interferences between geothermal systems. In this work, a management indicator (balanced sustainability index, BSI) applicable to groundwater heat pump systems is defined to assign a quantitative value of sustainability to each system, based on their intrinsic potential to produce thermal interference. The BSI indicator relies on the net heat balance transferred to the terrain throughout the year and the maximum seasonal thermal load associated. To define this indicator, 75 heating-cooling scenarios based in 23 real systems were established to cover all possible different operational conditions. The scenarios were simulated in a standard numerical model, adopted as a reference framework, and thermal impacts were evaluated. Two polynomial regression models were used for the interpolation of thermal impacts, thus allowing the direct calculation of the sustainability indicator developed as a function of heating-cooling ratios and maximum seasonal thermal loads. The BSI indicator could provide authorities and technicians with scientifically-based criteria to establish geothermal monitoring programs, which are critical to maintain the implementation rates and renewability of these systems in the cities

Uso de compostas y vermicompostas para la producción de tomate orgánico en invernadero

Una alternativa en la agricultura orgánica es la utilización de sustratos orgánicos. El objetivo del presente trabajo fue evaluar el efecto de tres compostas y tres vermicompostas mezcladas en diferentes proporciones (100, 75 y 50%) con arena, sobre el rendimiento y calidad de tomate, bajo condiciones de invernadero. Se utilizó el híbrido SUN-7705 de tomate (Solanum lycopersicum L.). Los 18 tratamientos se distribuyeron en un diseño completamente al azar con arreglo factorial 6×3 con cinco repeticiones en dos fechas de siembra. Se detectaron diferencias estadísticas entre fechas de siembra (p≤0,01). Los resultados indican que las mejores siete mezclas fueron vermicomposta de estiércol de ganado vacuno + rastrojo de maíz + tierra negra (VEMT) 75% + arena; vermicomposta de estiércol de ganado vacuno + pasto bahía (Paspalum notatum Flüggé) + tierra negra (VEPT) 100, 75 y 50% + arena; vermicomposta de estiércol de ganado vacuno + rastrojo de maíz + tierra negra (VEMT) 50% + arena; y vermicomposta de estiércol de ganado vacuno + rastrojo de maíz + zacate elefante (Pennisetum purpureum Schumacher; VEMZT) 100 y 75% + arena; con una media de 54,527t•ha-1. Los frutos de mayor tamaño se obtuvieron con la vermicomposta VEMT 75% + arena. El mayor contenido de sólidos solubles, se obtuvo con la mezcla VEPT 100% con 5,34ºBrix. Se concluye que se obtiene mayor rendimiento utilizando sustratos orgánicos con respecto al obtenido en producciones de tomate orgánico en campo, sin afectar la calidad del fruto