Determination of 15N stable isotope natural abundances for assessing the use of saline reclaimed water in grapefruit

We reported the results of an isotopic study aimed at evaluating the medium to long-term effects of different water qualities and deficit irrigation strategies on the ecophysiology of grapefruit in a 7-year-old plantation in SE Spain. For a better understanding of the interaction between nitrogen and salts from reclaimed water, RW, an experiment using natural abundance (δ) of 15N was conducted. This study showed that in grapefruit crop irrigated with RW leaf δ15N value increased. We concluded that: (i) causal links exist between leaf δ15N isotope and salt stress: positive correlation between values of this isotope and leaf salt content was showed; (ii) excess of nitrates provided by the reclaimed irrigation water were lost in the ecosystem through leaching, denitrification, etc., enriching the medium with δ15N and increasing δ15N values in plants. Therefore, the results of this study highlight the key role that salt content from RW can play in N uptake by plants and, hence, isotopic discrimination of leaf N. Consequently, it has been demonstrated the usefulness of isotopic discrimination measure to predict crop sustainability in the medium to long term when using water sources of different quality combined with deficit irrigation strategies

Irrigation scheduling and regulated deficit irrigation in stone fruits

In recent years the interest for applying irrigation techniques aiming to reduce water consumption has increased, mainly in areas with scarce water resources. We studied the effect of different regulated deficit irrigation (RDI) strategies on peach (Prunus persica (L.) Batsch cv. "Catherine") performance in Murcia (SE Spain) during three consecutive growing seasons. Three irrigation strategies were established: a control treatment, irrigated to fully satisfy the crop water requirements and two RDI treatments (moderate and severe) based on measurements of stem water potential (Ψs). Pruning weight, percentage of fruit categories, fruit diameter, crop load and yield were determined for each treatment. The results indicated that RDI treatments significantly reduced pruning weight. However, no significant differences were detected in terms of reproductive growth, fruit categories and yield. In the case of water productivity, the values for the RDI treatments were higher than those from the control. These results and water savings up to 50% indicate that RDI strategies constitute a possible solution against water shortages in areas such as the south-eastern region of Spain, although sustainability must be studied in the medium-long term.This study was supported by CONSOLIDER INGENIO 2010 (MEC CSD2006-0067)

Equations of motion for the out-of-equilibrium dynamics of isolated quantum systems from the projection operator technique

We present a rigorous framework to obtain evolution equations for the momentum distribution and higher order correlation functions in weakly interacting systems based on the Projection Operator Technique. These equations can be numerically solved in an efficient way. We compare the solution of the equations with known results for 1D models and find an excellent agreement.Instituto de Física La Plat

The Absent Double: Representations of the Disappeared

Estudio de las representaciones de las víctimas de masacres históricas a partir de la silueta y el doble.Fil: Kwiatkowski, Nicolás. Universidad Nacional de San Martín. Instituto de Altos Estudios Sociales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Burucua, José Emilio. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Effect of deficit irrigation and reclaimed water on yield and quality of grapefruits at harvest and postharvest

The aim of our research was to discover the effects of the long-term irrigation with saline reclaimed (RW) and transfer (TW) water and different irrigation strategies: control (C) and regulated deficit irrigation (RDI) on yield and fruit quality of grapefruit at harvest and during cold storage. T W-RDI treatment decreased tree canopy (TC) and crop load, resulting in a 21% reduction of fruit yield. Regarding fruit quality, RW notably decreased peel thickness at harvest (about 8%); however, this difference was not remained during cold storage. Sugar/acid ratio was mainly increased by RDI, but also by RW, due to an important increase in soluble solid content (11% of average value for TW-RDI, RW-C and RW-RDI). In addition, RDI combined with RW, significantly increased the number of fruits in small category 5 at the end of cold storage. Finally, neither ratio yield/TC nor irrigation water productivity were affected by any irrigation treatments.This study was supported by two CICYT projects (AGL2010-17553 and AGL2013-49047-C2- 515 2-R) projects and SENECA-Excelencia Científica (19903/GERM/15)

Quantum quench dynamics of the Coulomb Luttinger model

We study the nonequilibrium dynamics of the Luttinger model after suddenly turning on and off the bare Coulomb interaction between the fermions. We analyze several correlation functions such as the one particle density matrix and vertex correlations, its finite time dynamics, and the stationary state limit. Correlations exhibit a nonlinear light-cone effect: The spreading of the initial signal accelerates as a consequence of the quantum nature of the excitations, whose peculiar dispersion of plasmonic type in one dimension (1D) gives rise to a logarithmic divergence in the group velocity at q = 0. In addition, we show that both the static and dynamic stationary state correlations can be reproduced with a simple generalized Gibbs ensemble despite the long-range character of the interactions which precludes the application of the Lieb-Robinson bounds. We propose a suitable experimental setup in which these effect can be observed based on ultracold ions loaded on linear traps.Instituto de Física La Plat

Quenched dynamics of classical isolated systems: The spherical spin model with two-body random interactions or the Neumann integrable model

We study the Hamiltonian dynamics of the spherical spin model with fully-connected two-body random interactions. In the statistical physics framework, the potential energy is of the so-called p = 2 kind, closely linked to the scalar field theory. Most importantly for our setting, the energy conserving dynamics are equivalent to the ones of the Neumann integrable model. We take initial conditions from the Boltzmann equilibrium measure at a temperature that can be above or below the static phase transition, typical of a disordered (paramagnetic) or of an ordered (disguised ferromagnetic) equilibrium phase. We subsequently evolve the configurations with Newton dynamics dictated by a different Hamiltonian, obtained from an instantaneous global rescaling of the elements in the interaction random matrix. In the limit of infinitely many degrees of freedom, , we identify three dynamical phases depending on the parameters that characterise the initial state and the final Hamiltonian. We next set the analysis of the system with finite number of degrees of freedom in terms of N non-linearly coupled modes. We argue that in the limit the modes decouple at long times. We evaluate the mode temperatures and we relate them to the frequency-dependent effective temperature measured with the fluctuation-dissipation relation in the frequency domain, similarly to what was recently proposed for quantum integrable cases. Finally, we analyse the N - 1 integrals of motion, notably, their scaling with N, and we use them to show that the system is out of equilibrium in all phases, even for parameters that show an apparent Gibbs-Boltzmann behaviour of the global observables. We elaborate on the role played by these constants of motion after the quench and we briefly discuss the possible description of the asymptotic dynamics in terms of a generalised Gibbs ensemble.Fil: Cugliandolo, Leticia Fernanda. Université Pierre et Marie Curie; Francia. Université Pierre et Marie Curie. Laboratoire de Physique Théorique et Hautes Energies; FranciaFil: Lozano, Gustavo Sergio. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Física; Argentina. 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: Nessi, Emilio Nicolás. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Física; Argentina. 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: Picco, Marcos Fernando. Université Pierre et Marie Curie. Laboratoire de Physique Théorique et Hautes Energies; FranciaFil: Tartaglia, Alessandro. Université Pierre et Marie Curie. Laboratoire de Physique Théorique et Hautes Energies; Franci

Repositories in Google Scholar Metrics or what is this document type doing in a place as such?

The present paper analyzes GS Metrics, Google's newest product aiming at ranking journals according to their H-Index. Specifically, we analyze GS Metrics' decision of considering journals and repositories as equal and therefore, including them in the product. In this sense, the authors position themselves against this decision and provide several arguments of different nature warning against the shortcomings this product has. The first one is of a conceptual nature and is related to the definition of journal and repository. Secondly, they refer at the methodological issues mixing repositories and journals can bring out. Then, they deepen on many other flaws GS Metrics presents. Finally, GS Metrics and its possible use as an evaluation tool are discussed and possible solutions to its shortcomings are provided

Transpiration, photosynthetic responses, tissue water relations and dry mass partitioning in Callistemon plants during drought conditions

Callistemon is an Australian species used as ornamental plant in Mediterranean regions. The objective of this research was to analyse the ability of Callistemon to overcome water deficit in terms of adjusting its physiology and morphology. Potted Callistemon laevis Anon plants were grown in controlled environment and subjected to drought stress by reducing irrigation water by 40% compared to the control (irrigated to container capacity). The drought stress produced the smallest plants throughout the experiment. After three months of drought, the leaf area, number of leaves and root volume decreased, while root/shoot ratio and root density increased. The higher root hydraulic resistance in stressed plants caused decreases in leaf and stem water potentials resulting in lower stomatal conductance and indicating that water flow through the roots is a factor that strongly influences shoot water relations. The water stress affected transpiration (63% reduction compared with the control). The consistent decrease in gs suggested an adaptative efficient stomatal control of transpiration by this species, resulting in a higher intrinsic water use efficiency (Pn/gs) in drought conditions, increasing as the experimental time progressed. This was accompanied by an improvement in water use efficiency of production to maintain the leaf water status. In addition, water stress induced an active osmotic adjustment and led to decreases in leaf tissue elasticity in order to maintain turgor. Therefore, the water deficit produced changes in plant water relations, gas exchange and growth in an adaptation process which could promote the faster establishment of this species in gardens or landscaping projects in Mediterranean conditions.This work was supported by the projects: CICYT (AGL 2008-05258-C02-1-2), CDTI (IDI-20070868) and Fundación Seneca (05660/PI/07).Peer Reviewe