Comparing the impacts of drip irrigation by freshwater and reclaimed wastewater on the soil microbial community of two citrus species

[SPA] La búsqueda de nuevos recursos para el riego es un requerimiento en los agro ecosistemas mediterráneos. Se evaluó el impacto del riego con aguas de distintos suministros sobre la comunidad microbiana del suelo y sobre la fisiología de la planta en cultivos de pomelo y mandarino en el Sureste de España. Se consideraron los siguientes tratamientos: i) Agua procedente del Trasvase Tajo-Segura y de pozo (TW) ii) Agua regenerada procedente de una EDAR de la zona (RW) iii) Riego con TW, excepto en la segunda fase de desarrollo del fruto en la que se regó con RWc iv) Riego con RW, excepto en la segunda fase de desarrollo del fruto en la que se regó con TWc. [ENG] The search for new water resources for irrigation is a mandatory requirement in Mediterranean agroecosystems. The impacts of irrigation with water from different origins were evaluated in the soil microbial community and plant physiology of grapefruit and mandarin trees in the south-east of Spain. The following treatments were considered: i) freshwater from the Tajo-Segura water transfer canal and well (TW) ii) reclaimed water from a wastewater treatment plant ( RW) iii) irrigation with TW, except in the second stage of fruit development when RWc was applied iv) irrigation with RW, except in the second stage of fruit development when TWc was applied. Enzyme activities and phospholipids fatty acids were determined to know the phylum of microbial biomass.Authors are grateful to MINECO projects and Seneca foundation

Relativistic Effects in Extreme Mass Ratio Gravitational Wave Bursts

Extreme mass ratio bursts (EMRBs) have been proposed as a possible source for future space-borne gravitational wave detectors, such as the Laser Interferometer Space Antenna (LISA). These events are characterized by long-period, nearly-radial orbits of compact objects around a central massive black hole. The gravitational radiation emitted during such events consists of a short burst, corresponding to periapse passage, followed by a longer, silent interval. In this paper we investigate the impact of including relativistic corrections to the description of the compact object's trajectory via a geodesic treatment, as well as including higher-order multipole corrections in the waveform calculation. The degree to which the relativistic corrections are important depends on the EMRB's orbital parameters. We find that relativistic EMRBs (v_{max}}/c > 0.25) are not rare and actually account for approximately half of the events in our astrophysical model. The relativistic corrections tend to significantly change the waveform amplitude and phase relative to a Newtonian description, although some of this dephasing could be mimicked by parameter errors. The dephasing over several bursts could be of particular importance not only to gravitational wave detection, but also to parameter estimation, since it is highly correlated to the spin of the massive black hole. Consequently, we postulate that if a relativistic EMRB is detected, such dephasing might be used to probe the relativistic character of the massive black hole and obtain information about its spin.Comment: 13 pages, 8 figures, 2 tables. Replaced with version accepted for publication in the Ap.

Quenching of magnetic excitations in single adsorbates at surfaces: Mn on CuN/Cu(100)

The lifetimes of spin excitations of Mn adsorbates on CuN/Cu(100) are computed from first-principles. The theory is based on a strong-coupling T-matrix approach that evaluates the decay of a spin excitation due to electron-hole pair creation. Using a previously developed theory [Phys. Rev. Lett. {\bf 103}, 176601 (2009) and Phys. Rev. B {\bf 81}, 165423 (2010)], we compute the excitation rates by a tunneling current for all the Mn spin states. A rate equation approach permits us to simulate the experimental results by Loth and co-workers [Nat. Phys. {\bf 6}, 340 (2010)] for large tunnelling currents, taking into account the finite population of excited states. Our simulations give us insight into the spin dynamics, in particular in the way polarized electrons can reveal the existence of an excited state population. In addition, it reveals that the excitation process occurs in a way very different from the deexcitation one. Indeed, while excitation by tunnelling electrons proceeds via the s and p electrons of the adsorbate, deexcitation mainly involves the d electrons

Density operator of a system pumped with polaritons: A Jaynes-Cummings like approach

We investigate the effects of considering two different incoherent pumpings over a microcavity-quantum dot system modelled using the Jaynes-Cummings Hamiltonian. When the system is incoherently pumped with polaritons it is able to sustain a large number of photons inside the cavity with Poisson-like statistics in the stationary limit, and also leads to a separable exciton-photon state. We also investigate the effects of both types of pumpings (Excitonic and Polaritonic) in the emission spectrum of the cavity. We show that the polaritonic pumping as considered here is unable to modify the dynamical regimes of the system as the excitonics pumping does. Finally, we obtain a closed form expression for the negativity of the density matrices that the quantum master equation considered here generates.Comment: 16 pages, 4 figure

Bumpy Black Holes in Alternate Theories of Gravity

We generalize the bumpy black hole framework to allow for alternative theory deformations. We construct two model-independent parametric deviations from the Kerr metric: one built from a generalization of the quasi-Kerr and bumpy metrics and one built directly from perturbations of the Kerr spacetime in Lewis-Papapetrou form. We find the conditions that these "bumps" must satisfy for there to exist an approximate second-order Killing tensor so that the perturbed spacetime still possesses three constants of the motion (a deformed energy, angular momentum and Carter constant) and the geodesic equations can be written in first-order form. We map these parameterized metrics to each other via a diffeomorphism and to known analytical black hole solutions in alternative theories of gravity. The parameterized metrics presented here serve as frameworks for the systematic calculation of extreme-mass ratio inspiral waveforms in parameterized non-GR theories and the investigation of the accuracy to which space-borne gravitational wave detectors can constrain such deviations.Comment: 17 pages, replaced with version published in Phys. Rev.

Alternative water management strategies and his impact on the soil biology quality in semiarid agroecosystem

[SPA] En las regiones de clima semiárido, el agua es un factor limitante para la producción agrícola y, por tanto, para su desarrollo económico. Además, los escenarios de cambio climático muestran una reducción a medio plazo de los recursos hídricos con un mismo nivel de demanda. Por todo ello es fundamental implementar estrategias de riego dirigidas a paliar, en la medida de lo posible, la escasez de agua y a gestionar de manera más eficiente los escasos recursos disponibles. Por otra parte, la comunidad microbiana del suelo es un componente fundamental del ecosistema y un indicador claro de fertilidad del suelo. En el presente estudio se evalúa la respuesta de la comunidad microbiana del suelo, así como la fisiología y producción vegetal, ante las diferentes estrategias de manejo del agua de riego y el déficit hídrico. [ENG] In semiarid regions, water is a limiting factor for the agricultural production and hence for his economic development. Indeed, climate change scenarios show that water availability will be reduced on the long run, with a similar level of demand. Therefore, it is important to implement alternative irrigation managements in order to palliate water deficit without affecting soil sustainability. Moreover, the soil microbial community is an essential part of the ecosystem and a sensitive indicator of soil fertility. In this study, the responses of soil microbial community, plant physiology and production to alternative water managements and water deficit were evaluated in Mediterranean agroecosystems.Se agradece la financiación recibida del Ministerio de Economía y Competitividad, Programa Estatal de Investigación, Desarrollo e Innovación Orientada a los Retos de la Sociedad AGL2014-54636-R y AGL2016-77282-C3-1