Solute Tracer Tomography: Field Implementation and Parameter Estimation using the Ensemble Kalman Filter

The performance of groundwater flow and solute transport models depends, to a large extent, on the resolution at which aquifer heterogeneity is resolved. Large datasets are needed to estimate aquifer parameters at a high resolution, but their size is usually limited in real-world applications. The evolution of modern measurement techniques including better, smaller and affordable sensors have fostered the development of field tests with a tomographic layout, where the system is stressed in different directions. Recent numerical studies show the advantages of using large datasets of different type for describing small-scale features of aquifer properties. While hydraulic tomography, where multiple pumping tests are performed, has been repeatedly applied at field scale, applications of tracer tomography, where multiple tracer tests are performed, lag behind due to technical limitations. This study pursues to narrow the gap between numerical studies and field applications, showing the potential of hydraulic and tracer tomography for high-resolution aquifer characterization. In contrast to the few reported applications of tracer tomography, in which heat was used as a tracer, the experimental setup developed in this work was designed to use fluorescein as a conservative tracer, and was applied in the shallow alluvial aquifer at the Hydrogeological Research Site Lauswiesen, Germany. The experimental results demonstrate that solute-tracer tomography can be efficiently applied at the field scale, if a nested-cell forced-gradient flow field is generated prior to tracer injection. Field data were analyzed with the Ensemble Kalman Filter, coupled to a three dimensional groundwater flow and dual-domain transport model to estimate spatially distributed flow and solute transport parameters. The efficiency of the filter allows the description of aquifer heterogeneity at a high resolution while keeping reasonable computational costs. The filter was tested with a synthetic study based on a two dimensional model resembling the hydrogeological features and well facilities at the field site. The filter settings with the best performance were applied for the estimation of aquifer parameters based on real data. Results of the synthetic study show that parameters estimated with the Ensemble Kalman Filter applied to hydraulic data already contain the main features of the reference field. However, with the inclusion of concentration data the spatial structure of the parameter fields is accentuated, their uncertainty is considerably reduced, and flow and transport model predictions are improved. While the standard update scheme of the Ensemble Kalman Filter is applicable to hydraulic head, it leads to mass balance errors during assimilation of concentration data. Therefore, a restart scheme was applied where the steady-flow model is reinitialized after each parameter update, and transport is simulated from the initial time until the next available measurement time-step. The estimation of parameters based on drawdown curves measured during the field tracer tomography shows the potential of the Ensemble Kalman Filter in adjusting model parameters to improve groundwater flow simulations. When using the concentration data, the spatial structure of hydraulic conductivity was accentuated and the associated variance reduced. Transport simulations were largely affected by numerical dispersion, and by estimating effective transport parameters such as porosity and dispersivity as uniform values, rather than considering them as spatial fields. The Monte Carlo approach of the Ensemble Kalman Filter imposes limitations in the number of parameters that can be estimated, therefore efficient methods to optimize the grid resolution and reduce matrices dimensions are required

Warming reduces both photosynthetic nutrient use efficiency and water use efficiency in Mediterranean shrubsWarming reduces nutrient use efficiency

[EN] The ratio between net photosynthetic rates and the foliar contents of essential plant macronutrients (N, P, K) is termed photosynthetic nutrient use efficiency (PNutUE). A universal trade-off exists whereby plants cannot maximize their PNutUE and their intrinsic water use efficiency (WUEi, carbon gain per unit water spent) simultaneously, because any increase in intercellular CO2 concentration (ci) through a greater stomatal opening would increase PNutE but also enhances transpiration and therefore decreases WUEi. Rising temperatures associated with climate change can result in large decreases in WUEi in semiarid shrubs through photosynthetic machinery impairment and enhanced stomatal conductance and transpiration, but we know remarkably little about the influence of warming and drought on PNutUE and its interplay with WUEi in dryland vegetation. Using a 6-year (2011–2017) manipulative field experiment, we examined the effects of warming (2.5ºC, W), rainfall reduction (30%, RR), and their combination (W+RR) on the photosynthetic use efficiency of three essential nutrients (PNUE, PPUE and PKUE) and on WUEi in three shrub species growing at two semiarid shrublands for the years 2015–2017. Across species, warming (W and W+RR) reduced PNUE by 42.9%, PPUE by 43.8% and PKUE by 41.5% on average relative to shrubs growing under ambient temperatures, whereas RR did not significantly affect their PNutUE. These drastic reductions in PNutUE with warming were mainly driven by non-stomatal and largely non-nutritional decreases in net photosynthetic rates, which were almost halved in warmed shrubs. The photosynthetic use efficiencies of N, P and K were inversely related to foliar δ13C, a proxy for time integrated WUEi, in both ambient (control and RR) and warmed (W and W+RR) shrubs, but with significantly smaller slopes and intercepts for warmed shrubs. Thus, plants achieve a smaller gain in PNutUE for any given increase in stomatal conductance (and reduction in WUEi) under warmer climatic conditions. The strong negative impact of warming on PNutE, along with the warming-induced shift in the trade-off between PNutUE and WUEi, could be indicative of an increasing inability of native plants to cope with warmer conditions, with dire implications for dryland vegetation productivity and survival under climate change.S

Estimating Groundwater Recharge in Fully Integrated pde-Based Hydrological Models

Groundwater recharge is the main forcing of regional groundwater flow. In traditional partial-differential-equation (pde)-based models that treat aquifers as separate compartments, groundwater recharge needs to be defined as a boundary condition or it is a coupling condition to other compartments. Integrated models that treat the vadose and phreatic zones as a continuum allow for a more sophisticated calculation of subsurface fluxes, as feedbacks between both zones are captured. However, they do not contain an explicit groundwater-recharge term so it needs to be estimated by post-processing. Groundwater recharge consists of changes in groundwater storage and of the flux crossing the water table, which can be calculated based on hydraulic gradients. We introduce a method to evaluate the change of groundwater storage by a time-cumulative water balance over the depth section of water table fluctuations, avoiding the use of a specific yield. We demonstrate the approach first by a simple 1-D vertical model that does not allow for lateral outflow and illustrates the ambiguity of computing groundwater recharge by different methods. We then apply the approach to a 3-D model with a complex topography and subsurface structure. The latter example shows that groundwater recharge is highly variable in space and time with notable differences between regional and local estimates. Local heterogeneity of topography or subsurface properties results in complex redistribution patterns of groundwater. In fully integrated models, river-groundwater exchange flow may severely bias the estimate of groundwater recharge. We, therefore, advise masking out groundwater recharge at river locations

La cuarta revolución tecnológica: un nuevo paradigma de comprensión de la sociedad y el Estado más allá del big data e Internet

23 p.La cuarta revolución tecnológica, o la revolución de la información, produjo una serie de transformaciones que impactaron tanto la sociedad como la organización del Estado. Lo anterior, aunado a los procesos generados a partir de la globalización, presionó la reestructuración del Estado hacia estructuras flexibles de administración. Estas transformaciones se dan en el marco de una sociedad interconectada, donde se produce un permanente flujo de información. La posibilidad de que los ciudadanos interactúen entre sí y con las instituciones representa un reto para la estructura del Estado en el contexto de la globalización, en todos los aspectos, así como para todo el derecho en sus diferentes dimensiones (Sánchez, 2014, p. 27).Una revolución tecnológica Un mundo en cambio: contextos de la crisis Entre la tercera y cuarta revoluciones tecnológicas La integración de los sistemas: más allá del big data y la internet Las transformaciones del Estado: la influencia de la revolución tecnológica El gobierno y la democracia en la era digital Hacia una gobernanza digita

Marco teórico y aproximación jurídica al big data: algoritmos, inteligencia artificial y transformación digital

25 p.La expresión big data se debe al trabajo de Schönberger y Cukier (2013a). En español se utiliza también esta expresión inglesa. El Parlamento Europeo (2017) hace referencia a ‘macrodatos’, y no tanto a ‘datos masivos’: Recopilación, análisis y acumulación constante de grandes cantidades de datos, incluidos datos personales, procedentes de diferentes fuentes y objeto de un tratamiento automatizado mediante algoritmos informáticos y avanzadas técnicas de tratamiento de datos, utilizando tanto datos almacenados como datos transmitidos en flujo continuo, con el fin de generar correlaciones, tendencias y patrones (analítica de macrodatos).Apartes de este capítulo de libro fueron presentados y publicados por el Dr. Lorenzo Cotino en la sesión del Seminario de Derecho de la Universidad de Valencia, España; ponencia: “El Dret enfrontat las reptes del Big Data i l’automatització de les decisions”, del 26 de octubre de 2016, que puede consultarse en esta vínculo: https://www. uv.es/seminaridret/sesiones2017/bigdata/ponenciaCotino2016.pdf?Aproximación general al big data: premisas y cautelas ¿De dónde proceden los datos masivos y todo lo imaginable que se puede hacer con ellos? Algunas cautelas que plantea el big data y la necesidad de abordarlo jurídicamente Aproximación a elementos de economía colaborativa y transformación digital afines a la investigación Actores, actividades y sistemas de economía colaborativa La necesaria aproximación jurídica y nuevos enfoques desde los derechos fundamentales Datos masivos, discriminaciones y brecha masivas De la personalización masiva de la información al fin de la esfera pública y la posverdad: libertad de expresión artificial De la “oscuridad en el diseño” a la “transparencia algorítmica” y su fundamentación La aprehensión jurídica del fenómeno del big data desde la privacidad y el nuevo Reglamento europeo de protección de datos Los datos masivos rehúyen el régimen jurídico del derecho de protección de datos personales La anonimización de los datos masivos y sus dificultades para escaparse del derecho de protección de datos personales Graves dificultades de exigir el consentimiento para el tratamiento de datos masivos Dificultades para la proyección de los principios del derecho de protección de datos personales Dificultades para proteger los datos sensibles que se pueden generar a partir del big data Una aproximación a los usos de la inteligencia artificial y el big data en la aplicación automatizada de la le

Nuevo registro de siren intermedia (caudata: sirenidae) para el estado de Veracruz, México

The Lesser siren (Siren intermedia) is recorded for the first time in Tuxpan, for the second time in the state of Veracruz, and for the third time in Mexico. This finding increases the points of distribution of this species, previously reported from Matamoros and Ciudad Victoria, Tamaulipas and Gutierrez Zamora, Veracruz. This species has so far, a disjunct distribution in Mexico. La sirena menor (Siren intermedia) es registrada por primera vez en Tuxpan, por segunda vez en el estado de Veracruz y por tercera vez en México. Este hallazgo incrementa los puntos de  distribución de la especie, previamente informada para Matamoros y Ciudad Victoria, Tamaulipas y Gutiérrez Zamora, Veracruz. Hasta donde se sabe, esta especie tiene una distribución disyunta en México

New Nrf2-Inducer Compound ITH12674 Slows the Progression of Retinitis Pigmentosa in the Mouse Model rd10

Background/Aims: It is well established that oxidative stress and inflammation are common pathogenic features of retinal degenerative diseases. ITH12674 is a novel compound that induces the transcription factor Nrf2; in so doing, the molecule exhibits anti-inflammatory, and antioxidant properties, and affords neuroprotection in rat cortical neurons subjected to oxidative stress. We here tested the hypothesis that ITH12674 could slow the retinal degeneration that causes blindness in rd10 mice, a model of retinitis pigmentosa. Methods: Animals were intraperitoneally treated with 1 or 10 mg/Kg ITH12674 or placebo from P16 to P30. At P30, retinal functionality and visual acuity were analyzed by electroretinography and optomotor test. By immunohistochemistry we quantified the photoreceptor rows and analyzed their morphology and connectivity. Oxidative stress and inflammatory state was studied by Western blot, and microglia reactivity was monitored by flow cytometry. The blood−brain barrier permeation of ITH12674 was evaluated using a PAMPA-BBB assay. Results: In rd10 mice treated with 10 mg/Kg of the compound, the following changes were observed (with respect to placebo): (i) a decrease of vision loss with higher scotopic a- and b-waves; (ii) increased visual acuity; (iii) preservation of cone photoreceptors morphology, as well as their synaptic connectivity; (iv) reduced expression of TNF-α and NF-κB; (v) increased expression of p38 MAPK and Atg12-Atg5 complex; and (vi) decreased CD11c, MHC class II and CD169 positive cell populations. Conclusion: These data support the view that a Nrf2 inducer compound may arise as a new therapeutic strategy to combat retinal neurodegeneration. At present, we are chemically optimising compound ITH12674 with the focus on improving its neuroprotective potential in retinal neurodegenerative diseases.This work was supported by grants from Bayer (Grats4Targets), from the Spanish Ministry of Economy and Competitiveness (MINECO-FEDER BFU2015-67139-R), Spanish Ministry of Education (FPU14/03166, FPU13/03737 and FPU16/04114), Instituto de Salud Carlos III co-financed by the European Regional Development’s funds (FEDER) (RETICS-FEDER RD16/0008/0016, Programa Miguel Servet II (CP16/00014) and research project (grant PI17/01700)), Asociación Retina Asturias, Fundación La Caixa, CaixaImpulse program (grant CI17-00048), Comunidad Autónoma de Madrid (grant B2017/BMD-3827), Generalitat Valenciana (PROMETEO/2016/158 and ACIF/2016/055) Generalitat Valenciana-FEDER IDIFEDER/2017/064