Observation of ground-state quantum beats in atomic spontaneous emission

We report ground-state quantum beats in spontaneous emission from a continuously driven atomic ensemble. Beats are visible only in an intensity autocorrelation and evidence spontaneously generated coherence in radiative decay. Our measurement realizes a quantum eraser where a first photon detection prepares a superposition and a second erases the "which-path" information in the intermediate state.Comment: 4 pages, 4 figures, to appear in Phys. Rev. Letter

The role of secondary Reggeons in central meson production

We estimate the contribution of f_2 trajectory exchange to the central \eta and \eta^\prime production. It is shown that secondary Reggeons may give a large contribution to processes of double diffractive meson production at high energy.Comment: 7 pages, Latex, 5 figure

Effects of three-body collisions in a two-mode Bose-Einstein condenstate

We study the effects of three-body collisions in the basic physical properties of a two-mode Bose-Einstein condensate. By finding the exact analytical solution of a model which includes two-body and three-body elastic and mode-exchange collisions, we show analytically that three-body interactions produce observable effects in the probability distribution of the ground state and the dynamics of the relative population. In particular, we find that three-body interactions under certain circumstances inhibit collapse of the relative population.Comment: 5 pages, 3 figures. I.F. previously published as I. Fuentes-Schuller and I. Fuentes-Guridi. v2:minor changes, published versio

Feedback in a cavity QED system for control of quantum beats

Conditional measurements on the undriven mode of a two-mode cavity QED system prepare a coherent superposition of ground states which generate quantum beats. The continuous system drive induces decoherence through the phase interruptions from Rayleigh scattering, which manifests as a decrease of the beat amplitude and an increase of the frequency of oscillation. We report recent experiments that implement a simple feedback mechanism to protect the quantum beat. We continuously drive the system until a photon is detected, heralding the presence of a coherent superposition. We then turn off the drive and let the superposition evolve in the dark, protecting it against decoherence. At a later time we reinstate the drive to measure the amplitude, phase, and frequency of the beats. The amplitude can increase by more than fifty percent, while the frequency is unchanged by the feedback.Comment: 13 pages, 5 figures, ICAP 2012 23rd International Conference on Atomic Physic

ChIP-exo analysis highlights Fkh1 and Fkh2 transcription factors as hubs that integrate multi-scale networks in budding yeast

The understanding of the multi-scale nature of molecular networks represents a major challenge. For example, regulation of a timely cell cycle must be coordinated with growth, during which changes in metabolism occur, and integrate information from the extracellular environment, e.g. signal transduction. Forkhead transcription factors are evolutionarily conserved among eukaryotes, and coordinate a timely cell cycle progression in budding yeast. Specifically, Fkh1 and Fkh2 are expressed during a lengthy window of the cell cycle, thus are potentially able to function as hubs in the multi-scale cellular environment that interlocks various biochemical networks. Here we report on a novel ChIP-exo dataset for Fkh1 and Fkh2 in both logarithmic and stationary phases, which is analyzed by novel and existing software tools. Our analysis confirms known Forkhead targets from available ChIP-chip studies and highlights novel ones involved in the cell cycle, metabolism and signal transduction. Target genes are analyzed with respect to their function, temporal expression during the cell cycle, correlation with Fkh1 and Fkh2 as well as signaling and metabolic pathways they occur in. Furthermore, differences in targets between Fkh1 and Fkh2 are presented. Our work highlights Forkhead transcription factors as hubs that integrate multi-scale networks to achieve proper timing of cell division in budding yeast

El conflicto sirio y los recursos naturales

En la actualidad, los países ricos en recursos naturales que sustentan su economía principalmente de la extracción de minerales y la exportación de estos tienden al desarrollo de sociedades poco demo-cráticas, o incluso totalitarias, con índices de bajo crecimiento, altos niveles de desigualdad y conflictos (Brunnschweiler & Bulte, 2008). Además, las grandes potencias dominan, de manera clientelar, las zonas periféricas y dependientes, consolidando la subordinación no solo económica, sino también científica y tecnológica (Bruckman, 2012). A su vez, la necesidad de los recursos naturales de las distintas poblaciones y la tendencia creciente a una mayor demanda de energía y productos de origen natural genera en sí una disputa de carácter mundial, que afecta e involucra no solo cuestiones políticas, sino también económicas y militares (Forti, 2015). Países como Siria, y la región del valle del Éufrates, en general, carecen de una política integral referida a la protección del petróleo, y en defensa de los recursos naturales de la zona. Asimismo, no han podido evitar el quiebre del equilibrio interno y el Estado de Derecho, y mucho menos han logrado, o querido evitar la intromisión tanto de Rusia como de Estados Unidos en el conflicto. En este caso en particular se realizará un análisis de los recursos naturales y su vínculo con el conflicto sirio, su soberanía sobre la explotación del petróleo y la intervención de las potencias extranjeras en su territorio.Instituto de Relaciones Internacionale

Rescaling Social Welfare Policies in Italy. National report

Downloadable at: http://www.euro.centre.org/rescalingDocuments/files/Italy.pd