La infraestructura hidráulica y la gestión del agua en los regadíos tradicionales en la Vega Baja del Segura (Alicante)

La agricultura tradicional de la comarca de la Vega Baja del Segura se asienta sobre la llanura aluvial creada por el río a lo largo de la historia. Cuenta con una superficie regable de unos 190 km2 que se nutre con recursos propios de la cuenca del río Segura. Las aguas son desviadas del río mediante azudes y distribuidas, por simple gravedad, a través de un complejo sistema de acueductos, acequias y azarbes, que configuran sendas redes de aguas vivas y de aguas muertas, permitiendo la reutilización de las aguas. El presente trabajo tiene por finalidad el estudio de las infraestructuras hidráulicas y su papel en la gestión de los recursos hídricos para el riego en la comarca de la Vega Baja del Segura. A tal fin, se ha consultado la bibliografía y recabado información en diferentes juzgados de aguas, sindicatos de riego y comunidades de regantes, complementándose todo ello con visitas de campo para la toma de datos e imágenes. Los resultados obtenidos muestran una gestión eficiente de los escasos recursos hídricos disponibles y un aprovechamiento óptimo de los mismos, en cuanto que, al final, el sistema cede sus aguas sobrantes a otros regadíos para ser reutilizadas.

Coupled Biomechanical Response of the Cornea Assessed by Non-Contact Tonometry. A Simulation Study

The mechanical response of the cornea subjected to a non-contact air-jet tonometry diagnostic test represents an interplay between its geometry, the corneal material behavior and the loading. The objective is to study this interplay to better understand and interpret the results obtained with a non-contact tonometry test. A patient-specific finite element model of a healthy eye, accounting for the load free configuration, was used. The corneal tissue was modeled as an anisotropic hyperelastic material with two preferential directions. Three different sets of parameters within the human experimental range obtained from inflation tests were considered. The influence of the IOP was studied by considering four pressure levels (10–28 mmHg) whereas the influence of corneal thickness was studied by inducing a uniform variation (300–600 microns). A Computer Fluid Dynamics (CFD) air-jet simulation determined pressure loading exerted on the anterior corneal surface. The maximum apex displacement showed a linear variation with IOP for all materials examined. On the contrary, the maximum apex displacement followed a cubic relation with corneal thickness. In addition, a significant sensitivity of the apical displacement to the corneal stiffness was also obtained. Explanation to this behavior was found in the fact that the cornea experiences bending when subjected to an air-puff loading, causing the anterior surface to work in compression whereas the posterior surface works in tension. Hence, collagen fibers located at the anterior surface do not contribute to load bearing. Non-contact tonometry devices give useful information that could be misleading since the corneal deformation is the result of the interaction between the mechanical properties, IOP, and geometry. Therefore, a non-contact tonometry test is not sufficient to evaluate their individual contribution and a complete in-vivo characterization would require more than one test to independently determine the membrane and bending corneal behavior.

First EURONEAR NEA discoveries from La Palma using the INT

Since 2006, the European Near Earth Asteroids Research (EURONEAR) project has been contributing to the research of near-Earth asteroids (NEAs) within a European network. One of the main aims is the amelioration of the orbits of NEAs, and starting in 2014 February we focus on the recovery of one-opposition NEAs using the Isaac Newton Telescope (INT) in La Palma in override mode. Part of this NEA recovery project, since 2014 June EURONEAR serendipitously started to discover and secure the first NEAs from La Palma and using the INT, thanks to the teamwork including amateurs and students who promptly reduce the data, report discoveries and secure new objects recovered with the INT and few other telescopes from the EURONEAR network. Five NEAs were discovered with the INT, including 2014 LU14, 2014 NL52 (one very fast rotator), 2014 OL339 (the fourth known Earth quasi-satellite), 2014 SG143 (a quite large NEA), and 2014 VP. Another very fast moving NEA was discovered but was unfortunately lost due to lack of follow-up time. Additionally, another 14 NEA candidates were identified based on two models, all being rapidly followed-up using the INT and another 11 telescopes within the EURONEAR network. They include one object discovered by Pan-STARRS, two Mars crossers, two Hungarias, one Jupiter trojan, and other few inner main belt asteroids (MBAs). Using the INT and Sierra Nevada 1.5 m for photometry, then the Gran Telescopio de Canarias for spectroscopy, we derived the very rapid rotation of 2014 NL52, then its albedo, magnitude, size, and its spectral class. Based on the total sky coverage in dark conditions, we evaluate the actual survey discovery rate using 2-m class telescopes. One NEA is possible to be discovered randomly within minimum 2.8 deg2 and maximum 5.5 deg2. These findings update our past statistics, being based on double sky coverage and taking into account the recent increase in discovery.

Corneal biomechanics: a review

Biomechanics is often defined as ‘mechanics applied to biology’. Due to the variety and complexity of the behaviour of biological structures and materials, biomechanics is better defined as the development, extension and application of mechanics for a better understanding of physiology and physiopathology and consequently for a better diagnosis and treatment of disease and injury. Different methods for the characterisation of corneal biomechanics are reviewed in detail, including those that are currently commercially available (Ocular Response Analyzer and CorVis ST). The clinical applicability of the parameters provided by these devices are discussed, especially in the fields of glaucoma, detection of ectatic disorders and orthokeratology. Likewise, other methods are also reviewed, such as Brillouin microscopy or dynamic optical coherence tomography and others with potential application to clinical practice but not validated for in vivo measurements, such as ultrasonic elastography. Advantages and disadvantages of all these techniques are described. Finally, the concept of biomechanical modelling is revised as well as the requirements for developing biomechanical models, with special emphasis on finite element modelling.

Successional stage after land abandonment modulates fire severity and post-fire recovery in a Mediterranean mountain landscape

This study analyses the effect of successional stage after farmland terrace abandonment on post-fire plant recovery in a Mediterranean landscape. Specific objectives of the study were to (1) compare fuel characteristics and fire severity in three successional stages after farmland abandonment – dry grassland, dense shrubland and pine stands; (2) analyse the effect of pre-fire successional stage and fire severity on vegetation recovery and (3) analyse the relative vulnerability (i.e. potential for ecosystem shift and soil degradation) to wildfires of the successional stages. We assessed 30 abandoned terraces (15 unburned and 15 burned), with diverse successional stages, on the Xortà Range (south-east Spain). Post-fire recovery was measured 1, 4 and 7 years after fire. The successional stages varied in aboveground biomass, litter amount, vertical structure and continuity of plant cover, and flammability. Dry grassland showed the lowest fire severity, whereas no differences in severity were found between shrubland and pine stands. One year after fire, plant cover was inversely related to fire severity; this relationship attenuated with time after fire. Post-fire recovery of pine stands and shrubland led in both cases to shrublands, contributing to landscape homogenisation. The pine stands showed the largest changes in composition due to fire and the lowest post-fire plant recovery – a sign of high vulnerability to fire.

The activating role of phospho-(Tyr)-calmodulin on the epidermal growth factor receptor

The activity of calmodulin (CaM) is modulated not only by oscillations in the cytosolic concentration of free Ca2+, but also by its phosphorylation status. In the present study, the role of tyrosine-phosphorylated CaM [P-(Tyr)-CaM] on the regulation of the epidermal growth factor receptor (EGFR) has been examined using in vitro assay systems. We show that phosphorylation of CaM by rat liver solubilized EGFR leads to a dramatic increase in the subsequent phosphorylation of poly-L-(Glu:Tyr) (PGT) by the receptor in the presence of ligand, both in the absence and in the presence of Ca2+. This occurred in contrast with assays where P-(Tyr)-CaM accumulation was prevented by the presence of Ca2+, absence of a basic cofactor required for CaM phosphorylation and/or absence of CaM itself. Moreover, an antibody against CaM, which inhibits its phosphorylation, prevented the extra ligand-dependent EGFR activation. Addition of purified P-(Tyr)-CaM, phosphorylated by recombinant c-Src (cellular sarcoma kinase) and free of non-phosphorylated CaM, obtained by affinity-chromatography using an immobilized anti-phospho-(Tyr)-antibody, also increased the ligand-dependent tyrosine kinase activity of the isolated EGFR toward PGT. Also a CaM(Y99D/Y138D) mutant mimicked the effect of P-(Tyr)-CaM on ligand-dependent EGFR activation. Finally, we demonstrate that P-(Tyr)-CaM binds to the same site (645R-R-R-H-I-V-R-K-R-T-L-R-R-L-L-Q660) as non-phosphorylated CaM, located at the cytosolic juxtamembrane region of the EGFR. These results show that P-(Tyr)-CaM is an activator of the EGFR and suggest that it could contribute to the CaM-mediated ligand-dependent activation of the receptor that we previously reported in living cells.

Looking Forward to a Dynamic Third Age - Comparative Survey Report

BALL (Be Active Through Lifelong Learning) is an Erasmus + project of the European Union with the chief objective of analysing the degree of Preparation for Retirement among European citizens. The team working for this project, funded by the EU, is composed by organizations with broad experience at work with the third age from three European countries, Poland, Iceland and Spain, and the results obtained from these three contexts aim to provide a clear picture about the state of the art in preparation for retirement nowadays. The main objective of the project is to develop innovative guidelines and recommendations for use at lifelong learning centres; universities; companies; unions; associations; local and regional authorities who need and wish to prepare and encourage individuals under their auspices to prepare for the third age. The project defines the age group of 50 to 70 (the “baby boomer” generation) as the target group for such early preparations. The project and its outcomes will be used to raise awareness of these important issues and disseminate the results throughout the European Educational Area and the worldwide U3A network.

From community approaches to single-cell genomics: the discovery of ubiquitous hyperhalophilic Bacteroidetes generalists

The microbiota of multi-pond solar salterns around the world has been analyzed using a variety of culture-dependent and molecular techniques. However, studies addressing the dynamic nature of these systems are very scarce. Here we have characterized the temporal variation during 1 year of the microbiota of five ponds with increasing salinity (from 18% to >40%), by means of CARD-FISH and DGGE. Microbial community structure was statistically correlated with several environmental parameters, including ionic composition and meteorological factors, indicating that the microbial community was dynamic as specific phylotypes appeared only at certain times of the year. In addition to total salinity, microbial composition was strongly influenced by temperature and specific ionic composition. Remarkably, DGGE analyses unveiled the presence of most phylotypes previously detected in hypersaline systems using metagenomics and other molecular techniques, such as the very abundant Haloquadratum and Salinibacter representatives or the recently described low GC Actinobacteria and Nanohaloarchaeota. In addition, an uncultured group of Bacteroidetes was present along the whole range of salinity. Database searches indicated a previously unrecognized widespread distribution of this phylotype. Single-cell genome analysis of five members of this group suggested a set of metabolic characteristics that could provide competitive advantages in hypersaline environments, such as polymer degradation capabilities, the presence of retinal-binding light-activated proton pumps and arsenate reduction potential. In addition, the fairly high metagenomic fragment recruitment obtained for these single cells in both the intermediate and hypersaline ponds further confirm the DGGE data and point to the generalist lifestyle of this new Bacteroidetes group.

Interaction between diurnal variations of intraocular pressure, pachymetry, and corneal response to an air puff: Preliminary evidence

Diurnal changes in corneal geometry, pachymetry, and intraocular pressure (IOP) in a healthy eye were recorded. The deformation response to an air puff was simulated using 3 levels of corneal stiffness. The response was dependent on IOP and pachymetry and not only on the biomechanical properties of the cornea. Similarly, the maximum variability due to the diurnal changes in pachymetry and IOP in the corneal displacement generated by the air puff was found to reach 5%. Therefore, diurnal changes in IOP and corneal thickness were able to induce some variability in the air puff–based corneal deformation response. This potential variability should be considered when the biomechanical properties of the cornea are analyzed with air-puff devices.

Simulation of the secondary electrons energy deposition produced by proton beams in PMMA: influence of the target electronic excitation description

We have studied the radial dependence of the energy deposition of the secondary electron generated by swift proton beams incident with energies T = 50 keV–5 MeV on poly(methylmethacrylate) (PMMA). Two different approaches have been used to model the electronic excitation spectrum of PMMA through its energy loss function (ELF), namely the extended-Drude ELF and the Mermin ELF. The singly differential cross section and the total cross section for ionization, as well as the average energy of the generated secondary electrons, show sizeable differences at T ⩽ 0.1 MeV when evaluated with these two ELF models. In order to know the radial distribution around the proton track of the energy deposited by the cascade of secondary electrons, a simulation has been performed that follows the motion of the electrons through the target taking into account both the inelastic interactions (via electronic ionizations and excitations as well as electron-phonon and electron trapping by polaron creation) and the elastic interactions. The radial distribution of the energy deposited by the secondary electrons around the proton track shows notable differences between the simulations performed with the extended-Drude ELF or the Mermin ELF, being the former more spread out (and, therefore, less peaked) than the latter. The highest intensity and sharpness of the deposited energy distributions takes place for proton beams incident with T ~ 0.1–1 MeV. We have also studied the influence in the radial distribution of deposited energy of using a full energy distribution of secondary electrons generated by proton impact or using a single value (namely, the average value of the distribution); our results show that differences between both simulations become important for proton energies larger than ~0.1 MeV. The results presented in this work have potential applications in materials science, as well as hadron therapy (due to the use of PMMA as a tissue phantom) in order to properly consider the generation of electrons by proton beams and their subsequent transport and energy deposition through the target in nanometric scales.

La vulneración empresarial del derecho de huelga y responsabilidad por daños y perjuicios

Existen conductas empresariales de muy diversa naturaleza que pueden dar lugar a la transgresión del derecho de huelga. En estos casos se hace necesario reparar los daños que tales conductas provocan, tanto en el plano individual (trabajador) como en el plano colectivo (sindicatos u órganos de representación unitaria), teniendo en cuenta que la indemnización que derive de ello debe cumplir una función ejemplarizante, además de la propiamente reparadora. En el presente estudio, siguiendo los criterios que han ido sentando nuestros Tribunales, se identifican distintas conductas empresariales susceptibles de conculcar el derecho de huelga, a la par que se analizan todas y cada una de las partidas que debieran estar presentes a la hora de calcular el monto indemnizatorio, así como los criterios de valoración a tener en cuenta en estos casos.

Electronic properties of transition metal atoms on Cu2N/Cu(100)

We study the nature of spin excitations of individual transition metal atoms (Ti, V, Cr, Mn, Fe, Co, and Ni) deposited on a Cu2N/Cu(100) surface using both spin-polarized density functional theory (DFT) and exact diagonalization of an Anderson model derived from DFT. We use DFT to compare the structural, electronic, and magnetic properties of different transition metal adatoms on the surface. We find that the average occupation of the transition metal d shell, main contributor to the magnetic moment, is not quantized, in contrast with the quantized spin in the model Hamiltonians that successfully describe spin excitations in this system. In order to reconcile these two pictures, we build a zero bandwidth multi-orbital Anderson Hamiltonian for the d shell of the transition metal hybridized with the p orbitals of the adjacent nitrogen atoms, by means of maximally localized Wannier function representation of the DFT Hamiltonian. The exact solutions of this model have quantized total spin, without quantized charge at the d shell. We propose that the quantized spin of the models actually belongs to many-body states with two different charge configurations in the d shell, hybridized with the p orbital of the adjacent nitrogen atoms. This scenario implies that the measured spin excitations are not fully localized at the transition metal.

Derivation of the spin Hamiltonians for Fe in MgO

A method to calculate the effective spin Hamiltonian for a transition metal impurity in a non-magnetic insulating host is presented and applied to the paradigmatic case of Fe in MgO. In the first step we calculate the electronic structure employing standard density functional theory (DFT), based on generalized gradient approximation (GGA), using plane waves as a basis set. The corresponding basis of atomic-like maximally localized Wannier functions is derived and used to represent the DFT Hamiltonian, resulting in a tight-binding model for the atomic orbitals of the magnetic impurity. The third step is to solve, by exact numerical diagonalization, the N electron problem in the open shell of the magnetic atom, including both effects of spin–orbit and Coulomb repulsion. Finally, the low energy sector of this multi-electron Hamiltonian is mapped into effective spin models that, in addition to the spin matrices S, can also include the orbital angular momentum L when appropriate. We successfully apply the method to Fe in MgO, considering both the undistorted and Jahn–Teller (JT) distorted cases. Implications for the influence of Fe impurities on the performance of magnetic tunnel junctions based on MgO are discussed.