Bragg spectroscopy for measuring Casimir-Polder interactions with Bose-Einstein condensates above corrugated surfaces

We propose a method to probe dispersive atom-surface interactions by measuring via two-photon Bragg spectroscopy the dynamic structure factor of a Bose-Einstein condensate above corrugated surfaces. This method takes advantage of the condensate coherence to reveal the spatial Fourier components of the lateral Casimir-Polder interaction energy.Fil: Moreno, Gustavo Ariel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física de Buenos Aires; ArgentinaFil: Dalvit, Diego A. R.. Los Alamos National High Magnetic Field Laboratory; Estados UnidosFil: Calzetta, Esteban Adolfo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física de Buenos Aires; Argentin

Continuity and Robustness of Bayesian Equilibria in Tullock Contests

We study the continuity and robustness of the Bayesian equilibria of Tullock contests with incomplete information. We show that the Bayesian equilibrium correspondence is upper semicontinuous. We identify conditions under which the Bayesian equilibrium correspondence of Tullock contests with a unique equilibrium is also lower semicontinous. Furthermore, when the Bayesian equilibrium is unique, it is robust to small perturbations of the contest's attributes (the contest success function, and the players' information, value for the prize, and cost of effort).Acknowledgments of financial support: Ministerio Economía Spain, grants ECO2014-55953-P and MDM2014-0431, and Comunidad de Madrid, grant S2015/HUM-3444 (Moreno)

Biofilm formation in spent nuclear fuel pools and bioremediation of radioactive water

Microbiological studies of spent nuclear fuel pools at the Cofrentes Nuclear Power Plant (Valencia, Spain) were initiated to determine the microbial populations in the pools’ water. Biofilm formation at the nuclear power plant facilities and the potential use of those microbial populations in the bioremediation of radioactive water were also studied. Biofilm formation was analyzed by immersing different austenitic stainless steel coupons (UNS S30400, UNS S30466, UNS S31600), as well as balls of stainless steel (UNS S44200) and titanium (99.9%) in a spent nuclear fuel pool (under static and dynamic conditions) for 34 months. Epifluorescence microscopy and scanning electron microscopy revealed that biofilm formed on the samples, in spite of the radioactive and oligotrophic conditions of the water. Based on standard culture methods and sequencing of 16S rDNA fragments, 57 bacteria belonging to α-, β-, and γ-Proteobacteria, Firmicutes and Actinobacteridae were identified in the biofilms. The radioactivity of the biofilm was measured using γ-ray spectrometry, which revealed that biofilms were able to retain radionuclides, especially 60Co. Using metallic materials to decontaminate radioactive water could become a new approach for bioremediation. [Int Microbiol 2005 8(3):223-230

Brewster quasi bound states in the continuum in all-dielectric metasurfaces from single magnetic-dipole resonance meta-atoms

Bound states in the continuum (BICs) are ubiquitous in many areas of physics, attracting especial interest for their ability to confine waves with infinite lifetimes. Metasurfaces provide a suitable platform to realize them in photonics; such BICs are remarkably robust, being however complex to tune in frequency-wavevector space.Here we propose a scheme to engineer BICs and quasi-BICs with single magnetic-dipole resonance meta-atoms. Upon changing the orientation of the magnetic-dipole resonances, we show that the resulting quasi-BICs,emerging from the symmetry-protected BIC at normal incidence, become transparent for plane-wave illumination exactly at the magnetic-dipole angle, due to a Brewster-like effect. While yielding infinite Q-factors at normalincidence(canonical BIC), these are termed Brewster quasi-BICs since a transmission channel is always allowed that slightly widens resonances at oblique incidences. This is demonstrated experimentally through reflectance measurements in the microwave regime with high-refractive-index mm-disk metasurfaces. Such Brewster-inspired configuration is a plausible scenario to achieve quasi-BICs throughout the electromagnetic spectrum inaccessible through plane-wave illumination at given angles, which could be extrapolated to other kind of waves.Comment: 15 pages, 7 figures; typos corrected, Figs. 3 & 5 modified, new Fig. 7 & references adde

Tullock contests with asymmetric information

We show that under standard assumptions a Tullock contest with asymmetric information has a pure strategy Bayesian equilibrium. Moreover, two-player common-value Tullock contests in which one of the players has an information advantage have a unique equilibrium. In equilibrium both players exert the same expected effort, and although the player with information advantage wins the prize with probability less than one-half, his payoff is greater or equal to that of his opponent. In common-value Tullock contests with more players any information advantage is rewarded, but the other properties of two players contests do not holdMoreno gratefully acknowledges financial support from the Ministerio de Ciencia e Innovación, grant ECO2011-­2976

Desarrollo de una metodología de implementación de un Sistema de Gestión de Calidad en las empresas del sector eléctrico ecuatoriano. CASO TRANSELECTRIC S.A.

El desarrollo de una metodología para implementar un Sistema de Gestión de la Calidad, basado en la Norma ISO 9001:2000, para TRANSELECTRIC S.A., con la finalidad de optimizar los procesos y sus recursos, que permitan a la organización convertirse en una de alto desempeño y llegar a su Visión, para que sirva como referente a las demás empresas del sector que permita crear un modelo de gestión uniforme e integrado Este trabajo tratara varios capítulos que ayudan a definir esta metodología. El primer capítulo da una descripción de TRANSELECTRIC S.A. en su parte organizacional, en el segundo se trataran los temas teóricos de la calidad y la Norma ISO 9001:2000, además de metodologías referenciales de empresas consultoras y otros organismos asesores, en el tercer capítulo se hará un análisis de estas metodologías y se establecerán los requerimientos internos y externos de la compañía así como el estado actual del sistema de procesos. Por ultimo en el capítulo cuarto se propone una metodología que es una recopilación y adaptación de las otras metodologías descritas en el capítulo 2 y analizadas en el capítulo 3, en función la experiencia y de las características de la organización, buscando darle a esta un marco referencial que le ayude a implementar el Sistema de Gestión de Calidad que más allá de la certificación de a la organización de una estructura basada en procesos que le permita apalancar la mejora continua en el largo plazo. El éxito en la implementación de un Sistema de gestión de Calidad, basado en la Norma ISO 9001:2000, dependerá mucho del compromiso que se logre obtener de los directivos de TRANSELECTRIC S.A. y su motivación a buscar mejorar el desempeño de la organización, así como de la integración y convencimiento del beneficio de los trabajadores con esta iniciativa, es decir Gestión del Cambio. TRANSELECTRIC S.A. deberá aprovechar la sinergia y similitud que existe entra las Normas ISO 9001:2000, ISO 14001:2000 y la OHSAS 18001:2007, para en un solo esfuerzo planificar, diseñar, desarrollar e implementar un Sistema Integral de Gestión, de calidad, ambiente y seguridad y salud ocupacional y adoptar una herramienta informática que apalanque los procesos de la organización

Control structure and limitations of biochemical networks

Biochemical networks typically exhibit intricate topologies that hinder their analysis with control-theoretic tools. In this work we present a systematic methodology for the identification of the control structure of a reaction network. The method is based on a bandwidth reduction technique applied to the incidence matrix of the network’s graph. In addition, in the case of mass-action and stable networks we show that it is possible to identify linear algebraic dependencies between the time-domain integrals of some species’ concentrations. We consider the extrinsic apoptosis pathway and an activation– inhibition mechanism to illustrate the application of our result

Information in Tullock contest

We study the effect of changes of players' information on the equilibrium efforts and payoffs of Tullock contests in which the common value of the prize is uncertain. When the diseconomies of scale in exerting effort increase at a large (small) rate, in contests with symmetric information expected effort decreases (increases) as players become better informed, while in two-player contests with asymmetric information a player with information advantage exerts less (more) effort, in expectation, than his opponent. In classic Tullock contests with symmetric information the equilibrium expected effort and pay off are invariant to the information available to the players. And when information is asymmetric, a player's information advantage is rewarded. Moreover, in two-player contests, while both players exert the same expected effort regardless of their information, expected effort is smaller when one player has information advantage than when both players have the same information.Interestingly, the player with information advantage wins the prize less frequently than his opponent.Acknowledgment of financial support: Israel Science Foundation, grant 648/2 (Einy); Ministerio Economía (Spain), grants ECO2014-55953-P and MDM2014-0431, and Comunidad de Madrid, grant S2015/HUM-3444 (Moreno)