Inter-group conflict and intra-group punishment in an experimental contest game

We study how conflict in a contest game is influenced by rival parties being groups and by group members being able to punish each other. Our main motivation stems from the analysis of socio-political conflict. The relevant theoretical prediction in our setting is that conflict expenditures are independent of group size and independent of whether punishment is available or not. We find, first, that our results contradict the independence of group-size prediction: conflict expenditures of groups are substantially larger than those of individuals, and both are substantially above equilibrium. Towards the end of the experiment material losses in groups are 257% of the predicted level. There is, however, substantial heterogeneity in the investment behaviour of individual group members. Second, allowing group members to punish each other after individual contributions to the contest effort are revealed leads to even larger conflict expenditures. Now material losses are 869% of the equilibrium level and there is much less heterogeneity in individual group members' investments. These results contrast strongly with those from public goods experiments where punishment enhances efficiency and leads to higher material payoffs.

El Cancionero del Barón de Claret: fama de Lope de Vega y Calderón de la Barca en la Cataluña de la segunda mitad del siglo XVII

Comentari del llibre Cancionero del Barón de Claret, compilat a Catalunya. El comentari es centra en la influència de Lope de Vega i de Calderón de la Barca sobre aquesta obra. Resulta més influent Lope de Vega, malgrat que en el moment de la compilació de la obra ja no estava de moda, que Calderón de la Barca

La universalidad del concepto de libertad en La vida es sueño de Calderón de la Barca

Enfront dels corrents que neguen que l’ésser humà pugui ser autènticament lliure, La vida es sueño presenta una poderosa afirmació de la llibertat. Veritable refutació teològica en llenguatge dramàtic, l’obra de Calderón respon a les doctrines protestants de la seva època que propugnen la predestinació i el serf arbitri: els versos calderonians tradueixen l’ensenyament catòlic que afirma a Trento la cooperació del lliure albir a la moció de la gràcia. Així, el príncep encadenat per un fat que profetitzava la seva crueltat, conquereix la llibertat en acceptar la gràcia revelada a través del somni i mostrar-se com a sobirà just. Però més enllà del seu context, La vida es sueño pot rebatre també les teories que, com el psicoanàlisi, sostenen que els instints dominen l’home i li impedeixen ser lliure. En efecte, tot i deixar-se arrossegar per les passions en el seu primer alliberament, el protagonista no assoleix la llibertat fins que per mitjà de la virtut sotmet la seva voluntat a la recta raó i aconsegueix el domini sobre sí mateix. El concepte de llibertat que encarna Segismundo transcendeix la seva època i estableix un diàleg amb l’actualitat que entranya un gran potencial educatiu.

Critical ruptures in a bundle of slowly relaxing fibers

We study the damage enhanced creep rupture of disordered materials by means of a fiber bundle model. Broken fibers undergo a slow stress relaxation modeled by a Maxwell element whose stress exponent m can vary in a broad range. Under global load sharing we show that due to the strength disorder of fibers, the lifetime ʧ of the bundle has sample-to-sample fluctuations characterized by a log-normal distribution independent of the type of disorder. We determine the Monkman-Grant relation of the model and establish a relation between the rupture life tʄ and the characteristic time tm of the intermediate creep regime of the bundle where the minimum strain rate is reached, making possible reliable estimates of ʧ from short term measurements. Approaching macroscopic failure, the deformation rate has a finite time power law singularity whose exponent is a decreasing function of m. On the microlevel the distribution of waiting times is found to have a power law behavior with m-dependent exponents different below and above the critical load of the bundle. Approaching the critical load from above, the cutoff value of the distributions has a power law divergence whose exponent coincides with the stress exponent of Maxwell elements

IFRS introduction and its effect on listed companies in Spain

From the beginning of January 2005 publicly traded companies in the European Union have to comply with the International Financial Reporting Standards (IFRS) for their consolidated accounts, as required by 1606/2002 European Commission Regulation. It had been suggested that the new accounting rules will facilitate not only the process of international harmonization of financial statements, but also efficient performance of financial markets and capital flows worldwide. This study analyzes the first results of IFRS implementation by Spanish non-financial listed companies.

Finite-size scaling investigation of the liquid-liquid critical point in ST2 water and its stability with respect to crystallization.

The liquid-liquid critical point scenario of water hypothesizes the existence of two metastable liq- uid phases low-density liquid (LDL) and high-density liquid (HDL) deep within the supercooled region. The hypothesis originates from computer simulations of the ST2 water model, but the stabil- ity of the LDL phase with respect to the crystal is still being debated. We simulate supercooled ST2 water at constant pressure, constant temperature, and constant number of molecules N for N ≤ 729 and times up to 1 μs. We observe clear differences between the two liquids, both structural and dynamical. Using several methods, including finite-size scaling, we confirm the presence of a liquid-liquid phase transition ending in a critical point. We find that the LDL is stable with respect to the crystal in 98% of our runs (we perform 372 runs for LDL or LDL-like states), and in 100% of our runs for the two largest system sizes (N = 512 and 729, for which we perform 136 runs for LDL or LDL-like states). In all these runs, tiny crystallites grow and then melt within 1 μs. Only for N ≤ 343 we observe six events (over 236 runs for LDL or LDL-like states) of spontaneous crystal- lization after crystallites reach an estimated critical size of about 70 ± 10 molecules.

Selenium uptake by edible plants from enriched peat.

As a constituent of selenoproteins, selenium (Se) is considered an essential element for human health.The main way that Se enters the body is via the consumption of vegetables, whose concentration of thiselement depends on soil Se content. We grew cabbage, lettuce, chard and parsley, in peat enriched in Seby means of the additive Selcote Ultra®and Na2SeO3and Na2SeO4. Total Se in plants was determinedby acidic digestion and Se speciation by an enzymatic extraction. Both were measured by ICP/MS. Theconcentration ranges were between 0.1 mg Se kg−1and 30 mg Se kg−1for plants grown in Selcote Ultra®media, and between 0.4 mg Se kg−1and 1606 mg Se kg−1for those grown in peat enriched with Se sodiumsalts. We found Se (IV), Se (VI) and SeMet in all the extracts. Peat fortified with Selcote Ultra®gave slightlyhigher Se concentration than natural content values. For plants grown with selenium sodium salts, Secontent increases with the Se added and part of the inorganic Se was converted mainly to SeMet. A highSe fortification can damage or inhibit plant growth. Cabbage showed the greatest tolerance to Se.

Linear transceiver design in nonregenerative relays with channel state information

This paper deals with the design of nonregenerativerelaying transceivers in cooperative systems where channel stateinformation (CSI) is available at the relay station. The conventionalnonregenerative approach is the amplify and forward(A&F) approach, where the signal received at the relay is simplyamplified and retransmitted. In this paper, we propose an alternativelinear transceiver design for nonregenerative relaying(including pure relaying and the cooperative transmission cases),making proper use of CSI at the relay station. Specifically, wedesign the optimum linear filtering performed on the data to beforwarded at the relay. As optimization criteria, we have consideredthe maximization of mutual information (that provides aninformation rate for which reliable communication is possible) fora given available transmission power at the relay station. Threedifferent levels of CSI can be considered at the relay station: onlyfirst hop channel information (between the source and relay);first hop channel and second hop channel (between relay anddestination) information, or a third situation where the relaymay have complete cooperative channel information includingall the links: first and second hop channels and also the directchannel between source and destination. Despite the latter beinga more unrealistic situation, since it requires the destination toinform the relay station about the direct channel, it is useful as anupper benchmark. In this paper, we consider the last two casesrelating to CSI.We compare the performance so obtained with theperformance for the conventional A&F approach, and also withthe performance of regenerative relays and direct noncooperativetransmission for two particular cases: narrowband multiple-inputmultiple-output transceivers and wideband single input singleoutput orthogonal frequency division multiplex transmissions.

Una pintura d'Antoni Viladomat i Manalt (1678-1755) a Manresa : l'Assumpta de Santa Maria de l'Alba

This painting with an exceptional iconography of the Assumption of the Virgin with All the Saints, was saved from a altarpiece in the church of Santa Maria de l'Alba in Manresa, which was burnt during the Spanish Civil War. The article attributes this painting to Antoni Viladomat i Manalt (1678-1755), one of the most relevant figures in the Catalan artistic scene in the 18th century, and it dates it to the latter years of his extensive artistic career. An analysis of the work shows that the Catalan painter incorporated some figurative elements that he borrowed from an engraving of the Swiss engraver, Jakob Frey (1681-1752), interpreted from a canvas of the Italian painter Sebastiano Conca (1680-1764). This helps to relate the canvas of the Barcelona painter-based on his previous figurative work with high Roman baroque- to the new proposals of the so-called Roman barrochetto. In addition the study hopes to offer the reader an artistically cultural view of Antoni Viladomat, openly concerned by the novelties that constantly reached Catalonia by means of the engravings

El Jardín de Falerina, Francisco de Rojas Zorrilla, Antonio Coello Ochoa y Pedro Calderón de la Barca. Edición, introducción y notas de Felipe B. Pedraza Jiménez y Rafael González Cañal, (Barcelona: Octaedro, 2010)

Parece mentira que una pieza teatral firmada por Calderón de la Barca haya tardado más de tres cientos años en aparecer impresa y que sea ahora,en el 2010, cuando lo haga por primera vez. ¿A qué se debe esta falta de interés por la obra?La respuestanos la ofrecen Felipe B. Pedza Jiménez y Rafael González Cañal en el capítulo que abre el estudio preliminar de su edicion tulado«Razones de una sin razón»