702 research outputs found
Riesgos geomorfológicos pasados y presentes y pérdidas de patrimonio cultural en el escarpe del castillo de El Castellar (Cuenca Central del Ebro, España)
The ruins of the Medieval castle and village of El Castellar are located on an abrupt 1.2-km-long scarp of Miocene gypsums, in the central sector of the Ebro depression. The Medieval remains of the main El Castellar castle are perched on a 100 m cliff on the Ebro River. Considering the historical and geoarchaeological relevance of El Castellar settlement, this investigation aimed to study the geomorphological hazards and paleoenvironmental context of the site during and after the settlement and its later evolution, including its current state. To afford this objective the geomorphological context was determined analyzing the dynamics of each scarp sector. Geomorphological data suggest that in Medieval times its constructions were favored by the Medieval Climatic Anomaly (MCA) environmental conditions. During that times, the Ebro River was located in a centered position on its floodplain, and lateral alluvial fans protected the scarp from basal erosion. Later, during the Little Ice Age (LIA), great climatic flows and recurrent floods changed the river dynamics and promoted the river channel movement against the scarp, destabilizing its foot and generating large landslides and rockfalls, thus promoting its retreat. The village buildings and castle at the top of the scarp were seriously damaged. For several reasons, the area is not easily accessible, but it still contains a relevant archaeological heritage that deserves to be studied and preserved.Las ruinas del castillo medieval y villa de El Castellar se sitúan sobre un abrupto escarpe de yesos del Mioceno de 1,2 km de longitud, en el sector central de la Depresión del Ebro. Los restos medievales del castillo principal de El Castellar se alzan sobre un acantilado de 100 m sobre el río Ebro. Teniendo en cuenta la relevancia histórica y geoarqueológica del poblamiento de El Castellar, esta investigación tiene como objetivo estudiar los peligros geomorfológicos y el contexto paleoambiental del yacimiento durante y después del poblamiento y su evolución posterior, incluyendo su estado actual. Para lograr este objetivo se determinó el contexto geomorfológico analizando la dinámica de cada sector del escarpe. Los datos geomorfológicos sugieren que en época medieval sus construcciones se vieron favorecidas por las condiciones ambientales de la Anomalía Climática Medieval (ACM). En esa época, el río Ebro estaba situado en una posición centrada en su llanura de inundación, y los abanicos aluviales laterales protegían el escarpe de la erosión basal. Posteriormente, durante la Pequeña Edad del Hielo (LIA), grandes caudales y recurrentes inundaciones cambiaron la dinámica del río y promovieron el movimiento del cauce contra el escarpe, desestabilizando su pie y generando grandes derrumbes y desprendimientos, favoreciendo así su retroceso. Los edificios del pueblo y el castillo en la parte superior de la escarpa sufrieron graves daños. Por varias razones, la zona no es de fácil acceso, pero aún contiene un importante patrimonio arqueológico que merece ser estudiado y preservado.Fil: Peña Monné, José Luis. Universidad de Zaragoza. Facultad de Filosofía y Letras; EspañaFil: Sampietro Vattuone, Maria Marta. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; Argentina. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Laboratorio de Geoarqueología; ArgentinaFil: Espinalt Brillas, Marta. Oficina eSalut; EspañaFil: Gutiérrez González, Francisco J.. Universidad de Zaragoza. Facultad de Filosofía y Letras; Españ
Characterization and identification of field ectomycorrhizae of Boletus edulis and Cistus ladanifer
Field ectomycorrhizae sampled under Boletus edulis and Cistus ladanifer have been characterized and described in detail based on standard morphological and anatomical characters. The described ectomycorrhiza has traits typical of Boletales: whitish with three differentiated plectenchymatous layers in the mantle in plan view forming ring-like structures and rhizomorphs with highly differentiated hyphae. The inflated, smooth cystidia-like clavate end cells on the surface of the rhizomorphs and their slightly twisted external hyphae are additional characterizing features. The Hartig net occupies 1 1/2 rows of cortical cells, partly reaching the endodermis. Not all hyphae have clamps. The identification of the fungal symbiont as B. edulis was confirmed by ITS rDNA sequence comparison between mycorrhizas and sporocarps. The singularity of this symbiotic association, as well as its ecological and practical implications, are discussed
Identification of new sources of resistance to RHBV- rice hoja blanca virus
With the aim to find new sources of resistance to rice hoja blanca (white leaf) disease, transmitted by the insect Tagosodes orizicolus, 660 genotypes were evaluated under greenhouse and field conditions. Seven resistant genotypes were identified, and genomic studies were performed to demonstrate that the resistance in these sources is genetically different from that of Fedearroz 2000, which is currently the variety with the most resistance to hoja blanca. These new resistance sources constitute a resource that can be used to sustainably extend hoja blanca disease management throughout all of the rice-growing regions of tropical America. This is the first report of hoja blanca resistance in indica rice and different from that of Fedearroz 2000
Kinetic and equilibrium adsorption parameters estimation based on a heterogeneous intraparticle diffusion model
In this work, a commercial resin with a well-developed internal pore structure was chosen to adsorb four parabens used as probe molecules. The main novelty was to propose and validate a phenomenological transient adsorption model based on conservation law in both phases coupled with Langmuir’s equilibrium law and Fick’s mass transfer rate law inside the pores. With such an aim, a heterogeneous three-parameter intraparticle diffusion model, IPDM, was formulated, and its numerical solution was fitted to time-dependent concentration data by minimizing the sum of squared residuals. Equilibrium constants were also predicted by fitting Langmuir isotherm to equilibrium data. A monolayer capacity of 0.81 mmol/g was calculated for the four parabens regardless of the number of carbons in the ester group. With the optimal parameters values from the IPDM fitting process, a system of ODEs comprising local sensitivity coefficients as dependent variables was solved to compute the parameters’ variance-covariance matrix and infer their ranges for a 95% marginal confidence interval. In order to test the validity of the proposed model, an attempt to crosscheck between the parameters obtained by the estimation of the equilibrium related parameter, κ, and the modified capacity parameter, and the ones obtained by fitting the Langmuir’s isotherm to equilibrium data was carried out. As far as equilibrium related parameters concern, there is a relative agreement inside the limits of the confidence range between the estimated values of the amount adsorbed in equilibrium with initial bulk solution concentration, q0, and Langmuir’s equilibrium constant, K, adjusted to kinetic and equilibrium data, independently. Additionally, the order of magnitude of pore diffusivity obtained in this work is in accordance with the one predicted by Wilke-Chang correlation and is inversely proportional to the van der Waals volume raised to the power 0.53 in close agreement with the literature.The authors gratefully acknowledge financial support of this research work through the Comisión Interministerial de Ciencia y Tecnología (CICYT)-CTM2013-41354-R and Fundação para a Ciência e a Tecnologia (FCT)-UIDB/04730/2020 projects.info:eu-repo/semantics/publishedVersio
Integrating blocking and non-blocking MPI primitives with task-based programming models
In this paper we present the Task-Aware MPI library (TAMPI) that integrates both blocking and non-blocking MPI primitives with task-based programming models. The TAMPI library leverages two new runtime APIs to improve both programmability and performance of hybrid applications. The first API allows to pause and resume the execution of a task depending on external events. This API is used to improve the interoperability between blocking MPI communication primitives and tasks. When an MPI operation executed inside a task blocks, the task running is paused so that the runtime system can schedule a new task on the core that became idle. Once the blocked MPI operation is completed, the paused task is put again on the runtime system’s ready queue, so eventually it will be scheduled again and its execution will be resumed.
The second API defers the release of dependencies associated with a task completion until some external events are fulfilled. This API is composed only of two functions, one to bind external events to a running task and another function to notify about the completion of external events previously bound. TAMPI leverages this API to bind non-blocking MPI operations with tasks, deferring the release of their task dependencies until both task execution and all its bound MPI operations are completed.
Our experiments reveal that the enhanced features of TAMPI not only simplify the development of hybrid MPI+OpenMP applications that use blocking or non-blocking MPI primitives but they also naturally overlap computation and communication phases, which improves application performance and scalability by removing artificial dependencies across communication tasks.This work has been developed with the support of the European Union H2020 Programme through both the INTERTWinE project (agreement no. 671602) and the Marie Skłodowska-Curie grant (agreement no. 749516); the Spanish Ministry of Economy and Competitiveness through the Severo Ochoa Program (SEV-2015-0493); the Spanish Ministry of Science and Innovation (TIN2015-65316-P) and the Generalitat de Catalunya (2017-SGR1414).Peer ReviewedPostprint (author's final draft
“Face the cow”: reconnecting to nature and increasing capacities for pro-environmental agency
Arts-based practices can support sustainability, combined with research that points out needs for intervention. We practiced environmental sensitivity and dialogic art with fifth-grade school pupils as part of an International Socially Engaged Art Symposium (ISEAS2019). Using arts-based action research methodology, our case study focused on the opportunities of arts-based environmental education in advancing the management of meadows and wood-pastures. We explored nature connectedness and pro-environmental mindsets and behaviors among the pupils and artists/researchers. The artistic results encompassed the dialogic interactions of the intervention, exhibited artworks, and audiovisual documentation. Using the leverage points framework, we detected key levers in conservation of meadows and wood-pastures, based on literature and the current study through a content analysis on the collected reflective materials. The participants emphasized engaging with agricultural nature in multiple ways, through doing and feeling. Arts-based practices allowed participants to recognize their corporality and develop an experiental, expressive, and informed connection with nature. Based on discussions on the general ideologies and values underlying the intervention, we conclude that promoting a stewardship philosophy towards agricultural nature would benefit its conservation. Arts-based environmental education has great potential in advancing such transition, if the multidimensionality of the interaction between people and nature is acknowledged.</p
A low-mass planet candidate orbiting Proxima Centauri at a distance of 1.5 AU
Copyright © 2020 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC).Our nearest neighbor, Proxima Centauri, hosts a temperate terrestrial planet. We detected in radial velocities evidence of a possible second planet with minimum mass m c sin i c = 5.8 ± 1.9 M ⊕ and orbital period P c = 5.21 - 0.22 + 0.26 years. The analysis of photometric data and spectro-scopic activity diagnostics does not explain the signal in terms of a stellar activity cycle, but follow-up is required in the coming years for confirming its planetary origin. We show that the existence of the planet can be ascertained, and its true mass can be determined with high accuracy, by combining Gaia astrometry and radial velocities. Proxima c could become a prime target for follow-up and characterization with next-generation direct imaging instrumentation due to the large maximum angular separation of ~1 arc second from the parent star. The candidate planet represents a challenge for the models of super-Earth formation and evolution.Peer reviewedFinal Published versio
Síntesis de ectomicorrizas entre Cistus sp. y las especies del complejo Boletus edulis
En los jarales resultantes de la reiteración de incendios forestales en el oeste de Castilla y León (León, Salamanca y Zamora) es habitual la presencia de fructificaciones de Boletus edulis Bull. La recolección de estos hongos micorrícicos comestibles en los jarales dominados exclusivamente por Cistus ladanifer, supone una oportunidad económica alternativa a los usos tradicionales para zonas con bajos ingresos procedentes del monte.
El objetivo de éste trabajo es la obtención de ectomicorrizas de las especies del complejo B. edulis con Cistus sp. bajo condiciones controladas, y las descripciones anatómicas detalladas de las mismas. La identificación de los aislados fúngicos de Boletus aereus Bull., B. edulis, B.
reticulatus Schaeff. y B. pinophilus Pilát & Dermek fue confirmada por métodos moleculares.
Se han obtenido ectomicorrizas de Boletus aereus, B. edulis y B. reticulatus con Cistus
albidus L. y C. ladanifer en condiciones de síntesis en cultivo puro, en un substrato de turbavermiculita estéril y solución nutritiva. Las ectomicorrizas formadas se describieron siguiendo los caracteres anatómicos y morfológicos habituales. Las tres ectomicorrizas son muy similares, de color blanco, con ramificación monopodial-pinnada, manto formado por tres capas plectenquimatosas y con rizomorfos de tipo boletoide
Molecular dynamics simulation of surface phenomena due to high electronic excitation ion irradiation in amorphous silica
We studied by means of an atomistic model based on molecular dynamics the thermal evolution of surface atoms in amorphous silica under high electronic excitation produced by irradiation with swift heavy ions. The model was validated with the total and differential yields measured in sputtering experiments with different ions and ion energies showing a very good quantitative prediction capability. Three mechanisms are behind the evolution of the surface region: (1) an ejection mechanism of atoms and clusters with kinetic energy exceeding their binding energy to the sample surface, which explains the experimentally observed angular distributions of emitted atoms, and the correlation of the total sputtering yield with the electronic stopping power and the incidence angle. (2) A collective mechanism of the atoms in the ion track originated by the initial atom motion outwards the track region subsequently followed by the return to the resulting low-density region in the track center. The collective mechanism describes the energy dissipation of bulk atoms and the changes in density, residual stress, defect formation and optical properties. (3) A flow mechanism resulting from the accumulation and subsequent evolution of surface atoms unable to escape. This mechanism is responsible for the crater rim formation.Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. This work was funded by the projects Radiafus-5 (PID2019-105325RB-C32) of Spanish Ministry of Science, Technofusion (S2018/EMT-4437) of Madrid Regional Government and Eurofusion (EH150531176). The authors acknowledge the computer resources and technical assistance provided by the Centro de Supercomputación y Visualización de Madrid (CeSViMa) CESVIMA-MAGERIT. AP acknowledges the support of FONDECYT under grants 3190123. EMB thanks support from grant ANPCyT PICTO-UUMM-2019-00048. JK was supported by the Beatriz Galindo Program (BEAGAL18/00130) from the Ministerio de Educación y Formación Profesional of Spain
Global, regional, and national trends in haemoglobin concentration and prevalence of total and severe anaemia in children and pregnant and non-pregnant women for 1995–2011: a systematic analysis of population-representative data
Background Low haemoglobin concentrations and anaemia are important risk factors for the health and development
of women and children. We estimated trends in the distributions of haemoglobin concentration and in the prevalence
of anaemia and severe anaemia in young children and pregnant and non-pregnant women between 1995 and 2011.
Methods We obtained data about haemoglobin and anaemia for children aged 6–59 months and women of
childbearing age (15–49 years) from 257 population-representative data sources from 107 countries worldwide. We
used health, nutrition, and household surveys; summary statistics from WHO’s Vitamin and Mineral Nutrition
Information System; and summary statistics reported by other national and international agencies. We used a
Bayesian hierarchical mixture model to estimate haemoglobin distributions and systematically addressed missing
data, non-linear time trends, and representativeness of data sources. We quantifi ed the uncertainty of our estimates.
Findings Global mean haemoglobin improved slightly between 1995 and 2011, from 125 g/L (95% credibility interval
123–126) to 126 g/L (124–128) in non-pregnant women, from 112 g/L (111–113) to 114 g/L (112–116) in pregnant
women, and from 109 g/L (107–111) to 111 g/L (110–113) in children. Anaemia prevalence decreased from 33% (29–37)
to 29% (24–35) in non-pregnant women, from 43% (39–47) to 38% (34–43) in pregnant women, and from 47%
(43–51) to 43% (38–47) in children. These prevalences translated to 496 million (409–595 million) non-pregnant
women, 32 million (28–36 million) pregnant women, and 273 million (242–304 million) children with anaemia in
2011. In 2011, concentrations of mean haemoglobin were lowest and anaemia prevalence was highest in south Asia
and central and west Africa.
Interpretation Children’s and women’s haemoglobin statuses improved in some regions where concentrations had
been low in the 1990s, leading to a modest global increase in mean haemoglobin and a reduction in anaemia
prevalence. Further improvements are needed in some regions, particularly south Asia and central and west Africa, to
improve the health of women and children and achieve global targets for reducing anaemia.
Funding Bill & Melinda Gates Foundation, Grand Challenges Canada, and the UK Medical Research Council
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