814 research outputs found
Conflicts of interest, employment decisions, and debt restructuring: evidence from Spanish firms in financial distress
We examine the employment decisions of Spanish manufacturing firms in financial distress. Our sample comprises 4,566 firms operating during 1983-1994. We find that firms in distress reduce their employment significantly. These reductions are positively associated with asset sales, but cannot be fully explained by them. They are also negatively related to firm size and to firing costs. Our main finding, however, is that firms that restructure their debt in response to distress are more likely to reduce their employment. Employment falls as the firm's debt exposure is reduced, but also as a consequence of a bank debt restructuring involving exclusively an extension of maturity. These empirical findings provide a clear-cut quantitative illustration of the agency costs of debt emerging from stockholder-bondholder conflicts
Stability and robustness analysis of cooperation cycles driven by destructive agents in finite populations
The emergence and promotion of cooperation are two of the main issues in evolutionary game theory, as cooperation is amenable to exploitation by defectors, which take advantage of cooperative individuals at no cost, dooming them to extinction. It has been recently shown that the existence of purely destructive agents (termed jokers) acting on the common enterprises (public goods games) can induce stable limit cycles among cooperation, defection, and destruction when infinite populations are considered. These cycles allow for time lapses in which cooperators represent a relevant fraction of the population, providing a mechanism for the emergence of cooperative states in nature and human societies. Here we study analytically and through agent-based simulations the dynamics generated by jokers in finite populations for several selection rules. Cycles appear in all cases studied, thus showing that the joker dynamics generically yields a robust cyclic behavior not restricted to infinite populations. We also compute the average time in which the population consists mostly of just one strategy and compare the results with numerical simulations.Financial support from the Ministerio de Ciencia y Tecnología (Spain) under Projects No. FIS2009-13730-C02-02 (A.A.) and No. FIS2009-13370-C02-01 (J.C. and R.J.R.),
MOSAICO, PRODIEVO, and Complexity-NET RESINEE (J.A.C.); from the Barcelona Graduate School of Economics and the government of Catalonia (A.A.); from the Generalitat de Catalunya under Projects No. 2009SGR0838 (A.A.) and
No. 2009SGR0164 (J.C. and R.J.R.); and from Comunidad de Madrid under Project MODELICO-CM (J.A.C.) is appreciated.
R.J.R. acknowledges the financial support of the Universitat Autònoma de Barcelona and the Spanish government
Structure of Extremely Nanosized and Confined In-O Species in Ordered Porous Materials
Perturbed-angular correlation, x-ray absorption, and small-angle x-ray
scattering spectroscopies were suitably combined to elucidate the local
structure of highly diluted and dispersed InOx species confined in porous of
ZSM5 zeolite. These novel approach allow us to determined the structure of
extremely nanosized In-O species exchanged inside the 10-atom-ring channel of
the zeolite, and to quantify the amount of In2O3 crystallites deposited onto
the external zeolite surface.Comment: 4 pages, 5 postscript figures, REVTEX4, published in Physical Review
Letter
Monitoring climate change and child health: The case for putting children in all policies
Climate change is threatening the health of current and future generations of children. The most recent evidence from the Lancet Countdown: Tracking Progress on Health and Climate Change finds declining trends in yield potential of major crops, rising heatwave exposures, and increasing climate suitability for the transmission of infectious diseases, putting at risk the health and wellbeing of children around the world. However, if children are considered at the core of planning and implementation, the policy responses to climate change could yield enormous benefits for the health and wellbeing of children throughout their lives. Child health professionals have a role to play in ensuring this, with the beneficiaries of their involvement ranging from the individual child to the global community. The newly established Children in All Policies 2030 initiative will work with the Lancet Countdown to provide the evidence on the climate change responses necessary to protect and promote the health of children
The Joker effect: cooperation driven by destructive agents
Understanding the emergence of cooperation is a central issue in evolutionary
game theory. The hardest setup for the attainment of cooperation in a
population of individuals is the Public Goods game in which cooperative agents
generate a common good at their own expenses, while defectors "free-ride" this
good. Eventually this causes the exhaustion of the good, a situation which is
bad for everybody. Previous results have shown that introducing reputation,
allowing for volunteer participation, punishing defectors, rewarding
cooperators or structuring agents, can enhance cooperation. Here we present a
model which shows how the introduction of rare, malicious agents -that we term
jokers- performing just destructive actions on the other agents induce bursts
of cooperation. The appearance of jokers promotes a rock-paper-scissors
dynamics, where jokers outbeat defectors and cooperators outperform jokers,
which are subsequently invaded by defectors. Thus, paradoxically, the existence
of destructive agents acting indiscriminately promotes cooperation.Comment: Accepted for publication in the Journal of Theoretical Biology (JTB
Replicator dynamics with diffusion on multiplex networks
In this study we present an extension of the dynamics of diffusion in multiplex graphs, which makes the equations compatible with the replicator equation with mutations. We derive an exact formula for the diffusion term, which shows that, while diffusion is linear for numbers of agents, it is necessary to account for nonlinear terms when working with fractions of individuals. We also derive the transition probabilities that give rise to such macroscopic behavior, completing the bottom-up description. Finally, it is shown that the usual assumption of constant population sizes induces a hidden selective pressure due to the diffusive dynamics, which favors the increase of fast diffusing strategies
Comparison of in situ XAS and in situ PES in the soft X-ray range for the characterisation of heterogeneous catalytic processes
Cationic exchange in nanosized ZnFe2O4 spinel revealed by experimental and simulated near-edge absorption structure
The non-equilibrium cation site occupancy in nanosized zinc ferrites (6-13
nm) with different degree of inversion (0.2 to 0.4) was investigated using Fe
and Zn K-edge x-ray absorption spectroscopy XANES and EXAFS, and magnetic
measurements. The very good agreement between experimental and ab-initio
calculations on the Zn K-edge XANES region clearly show the large
Zn2+(A)--Zn2+[B] transference that takes place in addition to the
well-identified Fe3+[B]--Fe3+(A) one, without altering the long-range
structural order. XANES spectra features as a function of the spinel inversion
were shown to depend on the configuration of the ligand shells surrounding the
absorbing atom. This XANES approach provides a direct way to sense cationic
inversion in these spinel compounds. We also demonstrated that a mechanical
crystallization takes place on nanocrystalline spinel that causes an increase
of both grain and magnetic sizes and, simultaneously, generates a significant
augment of the inversion.Comment: 5 pages, 5 eps figures, uses revtex4, corrected table
- …