Opportunistic linked data querying through approximate membership metadata

Between URI dereferencing and the SPARQL protocol lies a largely unexplored axis of possible interfaces to Linked Data, each with its own combination of trade-offs. One of these interfaces is Triple Pattern Fragments, which allows clients to execute SPARQL queries against low-cost servers, at the cost of higher bandwidth. Increasing a client's efficiency means lowering the number of requests, which can among others be achieved through additional metadata in responses. We noted that typical SPARQL query evaluations against Triple Pattern Fragments require a significant portion of membership subqueries, which check the presence of a specific triple, rather than a variable pattern. This paper studies the impact of providing approximate membership functions, i.e., Bloom filters and Golomb-coded sets, as extra metadata. In addition to reducing HTTP requests, such functions allow to achieve full result recall earlier when temporarily allowing lower precision. Half of the tested queries from a WatDiv benchmark test set could be executed with up to a third fewer HTTP requests with only marginally higher server cost. Query times, however, did not improve, likely due to slower metadata generation and transfer. This indicates that approximate membership functions can partly improve the client-side query process with minimal impact on the server and its interface

Sap flow of a wild cherry tree plantation growing under Mediterranean conditions: Assessing the role of environmental conditions on canopy conductance and the effect of branch pruning on water productivity

In recent decades, wild cherry has been one of the species most widely used for reforestation in Europe. Studies aiming to select and improve trees to give them the best growth rates and wood properties have increased in response to growers’ demands. However, information relating to key physiological processes such as transpiration or stomatal conductance and to the effect of the common practice of pruning on plant–water relations is scarce. The main objective of this study was to assess the effects of environmental conditions on canopy conductance dynamics. Its secondary objective was to examine the short- and medium-term effects of branch pruning on tree transpiration, growth and derived water productivity. To this end, we measured sap flow in an experimental plantation where trees were subjected to drip irrigation and rain-fed conditions and where variables characterizing climate, soil and tree growth were also monitored. The results demonstrated that the Jarvis–Stewart approach was appropriate for studying the responses of canopy conductance to environmental factors. As well as the role of vapour pressure deficit and net radiation in controlling the daily variations of canopy conductance, the single effects of decreasing soil water content (optimum relative extractable water, REW, higher than 0.4) and increasing air temperature (optimum of 21 °C), as summer conditions approached, were correctly incorporated into the modelling exercise. Soil water content exerted the greatest control on canopy conductance for trees growing under rain-fed conditions, while air temperature did for irrigated trees. Pruning significantly reduced transpiration to about 35% when pre- and post-sub-periods were compared, but also affected annual water productivity regardless of the irrigation treatment. To assess the long-term effects of pruning on water productivity, measurements in both pruned and unpruned trees would be desirable.info:eu-repo/semantics/acceptedVersio

La imagen de la juventud en la publicidad televisiva

El Consejo Audiovisual de Navarra, máxima autoridad audiovisual en la Comunidad Foral de Navarra, tiene entre sus funciones básicas la elaboración de estudios que aporten luz al complejo y cambiante panorama audiovisual. Por esta razón se encomendó a la Facultad de Comunicación de la Universidad de Navarra la elaboración de este informe que analiza en profundidad la imagen de la juventud en la publicidad televisiva. Este Consejo Audiovisual espera haber ayudado de esta manera a fomentar la protección de la juventud en su exposición a los medios audiovisuales y a mejorar la imagen que de ella se da especialmente en la televisión, uno de los mayores factores de socialización, sino el que más, de los jóvenes de nuestra sociedad

Intervención psicoterapéutica cognitiva conductual grupal en pacientes ostomizados ambulatorios que presentan ansiedad y depresión asociadas a trastorno adaptativo

El presente estudio ha tenido como propósito esencial la aplicación y evaluación de un programa de corte cognitivo-conductual, para el manejo de los síntomas de ansiedad y depresión, en pacientes ostomizados. A través de un diseño de investigación de pretest, postest, con un solo grupo, fue evaluada la eficacia de una intervención cognitivo-conductual en grupo, aplicado a pacientes ostomizados que presentan trastorno de adaptación mixto. La muestra estuvo integrada por nueve pacientes con una edad promedio de 54 años, 4 eran mujeres y 5 eran hombres. El tratamiento fue ofrecido en 15 sesiones, una vez a la semana, con una duración de dos horas por sesión. Se utilizó para evaluar los síntomas de ansiedad y depresión en los participantes el inventario de ansiedad y depresión de Beck. Se pudo comprobar mediante el análisis estadístico de los resultados pretest y postest que la Terapia Cognitiva Grupal es efectiva en el tratamiento de pacientes ostomizados con trastorno adaptativo mixto debido a que el post test demostró que después de la aplicación del tratamiento se redujeron los síntomas depresivos y de ansiedad en el grupo de ostomizados

Spatial variability in the soil water content of a Mediterranean agroforestry system with high soil heterogeneity

Variability of soil water content is known to increase with the size of spatial domain in which measurements are taken. At field scale, heterogeneity in soil, vegetation, topography, water input volume and management affects, among other factors, hydrologic plot behaviour under different mean soil water contents. The present work studies how the spatial variability of soil water content (SWC) is affected by soil type (texture, percentage of stones and the combination of them) in a timber-orientated plantation of cherry tree (Prunus avium) under Mediterranean climatic conditions. The experimental design is a randomized block one with 3 blocks * 4 treatments, based on two factors: irrigation (6 plots irrigated versus 6 plots not irrigated) and soil management (6 plots tillaged versus 6 plots not tillaged). SWC is continuously measured at 25, 50 and 100 cm depth with FDR sensors, located at two positions in each treatment: under tree influence and 2.5 m apart. This study presents the results of the monitoring during 2012 of the 24 sensors located at the 25 cm depth. In each of the measurement point, texture and percentage of stones were measured. Sandy-loam, sandy-clay-loam and loam textures were found together with a percentage of stones ranging from 20 to 70 %. The results indicated that the relationship between the daily mean SWC and its standard deviation, a common procedure used to study spatial variability, changed with texture, percentage of stones and the estimation of field capacity from the combination of both. Temporal stability analysis of SWC showed a clear pattern related to field capacity, with the measurement points of the sandy-loam texture and the high percentage of stones showing the maximun negative diference with the global mean. The high range in the mean relative difference observed ( 75 %), could indicate that the studied plot may be considered as a good field-laboratory to extrapolate results at higher spatial scales. Furthermore, the pattern in the temporal stability of tree growth was clearly related to that one in SWC. Nevertheless, the treatments that represent the mean conditions in growth were not exactly the same than those in SWC, which could be attributable to other characteristics than soil

In Situ Bragg Coherent Diffraction Imaging Study of a Cement Phase Microcrystal during Hydration

Results of Bragg coherent diffraction imaging (BCDI) confirm that ion migration and consumption occur during hydration of calcium monoaluminate (CA). The chemical phase transformation promotes the hydration process and the formation of new hydrates. There is a potential for the formation of hydrates near where the active ions accumulate. BCDI has been used to study the in situ hydration process of CA over a 3 day period. The evolution of three-dimensional (3D) Bragg diffraction electron density, the “Bragg density”, and strain fields present on the nanoscale within the crystal was measured and visualized. Initial Bragg densities and strains in CA crystal derived from sintering evolve into various degrees during hydration. The variation of Bragg density within the crystal is attributed to the change of the degree of crystal ordering, which could occur through ion transfer during hydration. The observed strain, coming from the interfacial mismatch effect between high Bragg density and low Bragg density parts in the crystal, remained throughout the experiment. The first Bragg density change during the hydration process is due to a big loss of Bragg density as seen in the image amplitude but not its phase. This work provides new evidence supporting the through-solution reaction mechanism of CA

Water relations and vulnerability to embolism are not related: Experiments with eight grapevine cultivars

Drought tolerance mechanisms at the leaf level have been reported for grapevines but less is known about their vulnerability to embolism caused by water stress. The objective of this experiment was to determine if there is a relationship between xylem hydraulic characteristics and drought resistance mechanisms at the leaf level. The experiment was carried out on 10-year-old plants of 8 V. vinifera cvs: 'Sauvignon Blanc', 'Chardonnay', 'Cabernet Sauvignon', 'White Grenache', 'Black Grenache', 'Alicante Bouschet', 'Tempranillo', and 'Parellada' grown under field conditions without irrigation under Mediterranean climatic conditions. Embolism vulnerability curves were drawn for each cultivar. Values of the osmotic potential at full turgor, and at the turgor loss point, and the leaf bulk modulus of elasticity were obtained from pressure-volume curves on 4 different dates, from berries at pea size until harvest. All cultivars except 'Chardonnay', which showed elastic adjustment, showed osmoregulation but different patterns in vulnerability curves were found for each cultivar. While 'Parellada', 'Tempranillo' and 'Black Grenache' proved to have the most vulnerable xylem, 'Chardonnay' and 'Sauvignon Blanc' were shown to have the least vulnerable xylem to embolism. There was no relationship between the level of vulnerability to embolism for each cultivar and the drought tolerance mechanisms at the leaf level under the environmental conditions of this experiment. &nbsp

A non-separability measure for spatially disjoint vectorial fields

Vectorial forms of structured light that are non-separable in their spatial and polarisation degrees of freedom have become topical of late, with an extensive toolkit for their creation and control. In contrast, the toolkit for quantifying their non-separability, the inhomogeneity of the polarisation structure, is less developed and in some cases fails altogether. To overcome this, here we introduce a new measure for vectorial light, which we demonstrate both theoretically and experimentally. We consider the general case where the local polarisation homogeneity can vary spatially across the field, from scalar to vector, a condition that can arise naturally if the composite scalar fields are path separable during propagation, leading to spatially disjoint vectorial light. We show how the new measure correctly accounts for the local path-like separability of the individual scalar beams, which can have varying degrees of disjointness, even though the global vectorial field remains intact. Our work attempts to address a pressing issue in the analysis of such complex light fields, and raises important questions on spatial coherence in the context of vectorially polarised light

L'Espectrometria de masses aplicada a la caracterització de materials

En aquest article hom pretén revisar en primer lloc, els principis de funcionament d'un espectròmetre de masses així com els principals desenvolupaments experimentals que aquesta tècnica ha assolit en l'actualitat. Per aquesta raó hom discutirà sobre diferents fonts d'ionització tant clàssiques (impacte electrònic, ionització química...) com d'altres dissenyades per a analitzar materials no volàtils. El concepte d'espectròmetre de doble enfocament també serà revisat. Hom introduirà els principis bàsics que permeten d'obtenir les anàlisi SIMS (Secondary Ion Mass Spectrometry) i els anomenats "ion imaging". Ha merescut una atenció especial la disposició FAB-CAD-MIKES (Fast Atom Bombardment – Collission Activated Decay- Mass Analysed Ion Kinetic Energy Spectrometry). També seran presentades algunes experiències realitzades amb aquestes tècniques.This paper reviews firstly the basis of a mass spectrometer and the main experimental developments reachead by this technique up to now. Different classical ionization sources (such as electron impact,chemical ionization ) and those developed for the analysis of non volatile materials as well as the concept of double focalization mass spectrometer will be discussed. Furthermore the principles of S.I.M.S. analysis and ion imaging, will be considered. Special attention will be devoted to the joint application of F.A.B.-C.A.D.-M.I.K.E.S. techniques. Finally, some experiences carried out with these techniques are reported

Elongation and fluctuations of semi-flexible polymers in a nematic solvent

We directly visualize single polymers with persistence lengths ranging from $\ell_p=0.05$ to 16 $\mu$m, dissolved in the nematic phase of rod-like {\it fd} virus. Polymers with sufficiently large persistence length undergo a coil-rod transition at the isotropic-nematic transition of the background solvent. We quantitatively analyze the transverse fluctuations of semi-flexible polymers and show that at long wavelengths they are driven by the fluctuating nematic background. We extract both the Odijk deflection length and the elastic constant of the background nematic phase from the data.Comment: 4 pages, 4 figures, submitted to PR