Consideraciones sobre la dinámica geomorfológica actual de laderas semiáridas de la Depresión del Ebro: el caso de la Val de las Lenas (término municipal de María de Huerva, Zaragoza, España)

[Resumen] En este trabajo se realiza una aproximación al funcionamiento geomorfológico actual de las vales del semiárido aragonés. Las investigaciones contemplan sucesivas aproximaciones, en las que se analizarán: (1) la evolución de humedad en el suelo en diferentes profundidades y posiciones de ladera, (2) las variaciones de la textura del depósito y (3) la simulación de lluvia. Los resultados indican la posible existencia de un funcionamiento hidrológico dislocado a lo largo de la ladera entre el talud superior y los niveles basales. A lo largo del relleno, además, la franja superior parece depender hidrológicamente de su proximidad al talud rocoso adyacente (funcionamiento alóctono), mientras que el depósito de val parece comportarse hidrológicmente de manera autóctona. Entre las partes altas y bajas del relleno de val se aprecia una inversión de las condiciones hídricas que definen su potencial biológico, cuyo reparto espacial es inverso al esperado.[Abstract] We have studied the geomorphological behaviour of slope in a semiarid landscape (NE inland Spain). The approach have been done by the analysis of soil water evolution, particle size analysis and rainfall simulation from top to bottom of slope. Results suggest the posibility of hidrological compartimentation between upper free face and talus; talus is not homogeneous, and there exist a strip in the contact zone with upper free face which change the hidrological regime from upper to lower part of talus

The response of Iberian rivers to the North Atlantic Oscillation

In this study we analyzed the influence of the North Atlantic Oscillation (NAO) on the streamflow in 187 sub-basins of the Iberian Peninsula. Monthly and one-month lagged correlations were conducted to assess the spatio-temporal extent of the NAO influence on Iberian river discharges. Analysis of the persistence of the winter NAO throughout the year was also undertaken, together with analysis of streamflow anomalies during positive and negative NAO phases. Moving-window correlation analyses were conducted to assess potential changes in the temporal evolution of the NAO influence on Iberian streamflows. The results show that the NAO has a large impact on surface water resources throughout the Iberian Peninsula during winter, and in the Atlantic watershed during autumn. We showed that water resources management and snowmelt are causing the persistent dependence of streamflows on the previous winter NAO. We found that strongly positive streamflow anomalies occurred during winter, especially in the Atlantic watershed, and provide evidence of non-stationarity and spatial variability in the NAO influence on Iberian water resources

Diferencias en la evolución del paisaje entre dos municipios Prepirenaicos: Alquézar y Valle de Lierp, en la segunda mitad del siglo XX

Rapid socio-economical global changes happened during the second half of the 20th century, have radically altered territorial management in rural areas of the Mediterranean mountains, specifically, in the Pre Pyrenees (Huesca). Population decrease in young and economically active members, plus the change of the productive model entailed a land use transformation and subsequent landscape changes. Although the general model of landscape change is based on the decrease of human pressure on this territory, we should also take into account local characteristics related to biophysical and historical features. The comparison between two Pre Pyrenean municipalities: Alquézar and Valle de Lierp, shows these local differences, contextualized by the analyses of the Pre Pyrenean landscape composition. Consequently, a retrospective and multiscale study focused on the two sample municipalities –considering those as an operational management unit–, has been done. We have assessed landscape composition, configuration and structure on those units through component analyses, transition models and landscape indices. The methodological development of this work has been simplified by the use of GIS (ARC GIS 9) and FRAGSTAT, software of landscape ecology metrics.Los rápidos cambios socioeconómicos globales ocurridos durante la segunda mitad del siglo XX transformaron radicalmente el sistema de gestión territorial en el ámbito rural de la montaña mediterránea y, concretamente, en el Prepirineo oscense. La disminución de la población joven y activa económicamente, así como la transformación del modelo productivo, conllevaron un cambio en la estrategia tradicional de aprovechamiento y ocupaciones del suelo, que ha dejado su impronta en el paisaje. No obstante, las particularidades locales biofísicas e históricas condicionan la aparición de matizaciones al modelo de transformación general del paisaje, basado fundamentalmente en la disminución de la presión humana sobre el territorio. El contraste entre dos municipios en el ámbito del Prepirineo oscense (Alquézar y Valle de Lierp) ilustra estas variaciones, contextualizadas por el análisis de la composición del paisaje del Prepirineo oscense. Se realiza, por lo tanto, un estudio retrospectivo y multiescala centrado en la unidad operacional que constituye el municipio, donde se evalúa la composición, configuración y estructura del paisaje a través del análisis de sus componentes, de modelos de transición y de la aplicación de índices de paisaje. El desarrollo metodológico de este trabajo se ha simplificado gracias al empleo de SIG (ARC GIS.9) y FRAGSTAT, un programa de índices de ecología del paisaje

The Star Formation History of M32

We use deep HST ACS/HRC observations of a field within M32 (F1) and an M31 background field (F2) to determine the star formation history (SFH) of M32 from its resolved stellar population. We find that 2-5Gyr old stars contribute \som40%+/- 17% of M32's mass, while 55%+/-21% of M32's mass comes from stars older than 5 Gyr. The mass-weighted mean age and metallicity of M32 at F1 are =6.8+/-1.5 Gyr and =-0.01+/-0.08 dex. The SFH additionally indicates the presence of young (<2 Gyr old), metal-poor ([M/H]\sim-0.7) stars, suggesting that blue straggler stars contribute ~2% of the mass at F1; the remaining \sim3% of the mass is in young metal-rich stars. Line-strength indices computed from the SFH imply a light-weighted mean age and metallicity of 4.9 Gyr and [M/H] = -0.12 dex, and single-stellar-population-equivalent parameters of 2.9+/-0.2 Gyr and [M/H]=0.02+/-0.01 dex at F1 (~2.7 re). This contradicts spectroscopic studies that show a steep age gradient from M32's center to 1re. The inferred SFH of the M31 background field F2 reveals that the majority of its stars are old, with \sim95% of its mass already acquired 5-14 Gyr ago. It is composed of two dominant populations; \sim30%+/-7.5% of its mass is in a 5-8 Gyr old population, and \sim65%+/-9% of the mass is in a 8-14 Gyr old population. The mass-weighted mean age and metallicity of F2 are =9.2+/-1.2 Gyr and =-0.10+/-0.10 dex, respectively. Our results suggest that the inner disk and spheroid populations of M31 are indistinguishable from those of the outer disk and spheroid. Assuming the mean age of M31's disk at F2 (\sim1 disk scale length) to be 5-9 Gyr, our results agree with an inside-out disk formation scenario for M31's disk.Comment: Accepted to ApJ. 24 pages, 18 figures. A high-resolution version can be downloaded from http://www.astro.rug.nl/~monachesi/monachesi-sfh.pd

Effectiveness of Protein Supplementation Combined with Resistance Training on Muscle Strength and Physical Performance in Elderly: A Systematic Review and Meta-Analysis

The aim of this study was to evaluate the effectiveness of the combination of resistance training (RT) and protein supplementation (PS), compared to RT alone or combined with a placebo (plS), in the improvement of muscle strength and physical performance. The search strategy in PubMed, Cochrane Library, and Web of Sciences databases found a total of 294 studies. Once inclusion and exclusion criteria were applied, 16 studies were included for the qualitative analysis. A total of 657 healthy elderly (>60 years) participants were analysed. Finally, 15 articles were included in the quantitative analysis with one being excluded due to issues with data availability. Upper-limb, lower-limb, and handgrip strength were the primary outcomes of the meta-analysis. The secondary outcomes, related to physical performance, were Short Physical Performance Battery (SPPB), gait speed, and the five-chair-rise test (5CRT). The main results of the meta-analysis show no statistical differences for upper-limb (SMD: 0.56, 95% CI: -0.09, 1.21, p = 0.09, I2 = 68%), lower-limb (SMD: 0.00, 95% CI: -0.18, 0.18, p = 1.0, I2 = 11%), and handgrip strength (SMD: 0.03, 95% CI: -0.26, 0.32, p = 0.84, I2 = 0%) between the RT + PS and the RT alone (or combined with plS). Moreover, no statistical differences were found relating to physical performance. In view of these results, protein supplementation combined with RT does not provide additional benefits compared to RT alone or with plS in healthy elderly adults

Red Dots: A temperate 1.5 Earth-mass planet candidate in a compact multi-terrestrial planet system around GJ 1061

Abstract Small low-mass stars are favourable targets for the detection of rocky habitable planets. In particular, planetary systems in the solar neighbourhood are interesting and suitable for precise characterisation. The Red Dots campaigns seek to discover rocky planets orbiting nearby low-mass stars. The 2018 campaign targeted GJ 1061, which is the 20th nearest star to the Sun. For three consecutive months we obtained nightly, high-precision radial velocity measurements with the HARPS spectrograph. We analysed these data together with archival HARPS data. We report the detection of three planet candidates with periods of 3.204 ± 0.001, 6.689 ± 0.005 and 13.03 ± 0.03 days, which are close to 1:2:4 period commensurability. After several considerations related to the properties of the noise and sampling, we conclude that a 4th signal is most likely explained by stellar rotation, although it may be due to a planet. The proposed three-planet system (and the potential four-planet solution) is long-term dynamically stable. Planet-planet gravitational interactions are below our current detection threshold. The minimum masses of the three planets range from 1.4±0.2 to 1.8±0.3 M⊕. Planet d, with msin i = 1.64 ± 0.24M⊕, receives a similar amount of energy as Earth receives from the Sun. Consequently it lies within the liquid-water habitable zone of the star and has a similar equilibrium temperature to Earth. GJ 1061 has very similar properties to Proxima Centauri but activity indices point to lower levels of stellar activity

Structure of dislocations in Al and Fe as studied by positron-annihilation spectroscopy

Positron-lifetime-spectra measurements have been performed on single crystals of Al and polycrystals of Fe deformed under the tensile mode at room temperature and 77 K, respectively. It is shown that the positron-trapping component in Al depends on the number of slip systems activated: The positron lifetime is 215, 220, and 240 ps when single-, double-, and multiple-slip planes are activated, respectively. This dependence is well understood if positrons annihilate at dislocation-associated defects (jogs) with different positron-annihilation characteristics revealing different jog structures. In iron, the positron-lifetime spectra associated with dislocations were found to be independent of the annealing temperature between 110 and 360 K. In this temperature range, screw dislocations should transform into nonscrew dislocations, suggesting that the positrons are not sensitive to the different types of dislocations. These results are interpreted on the basis that positrons annihilate at defects associated with the dislocations rather than at the dislocation lines. © 1992 The American Physical Society.Peer Reviewe

Assessing the sensitivity of data-limited methods for resources in the Atlantic waters

ICES Annual Science Conference 2021, online 6-10 SeptemberLength-based methods have been widely applied to estimate biological parameters and to under-stand the dynamics of marine resource populations within the category of data-limited stocksThe authors thank the financial support of the project IMPRESS (RTI2018-099868-B-I00) project, ERDF, Ministry of Science, Innovation and Universities - State Research Agency, and also of GAIN (Xunta de Galicia), GRC MERVEX (nº IN607-A 2018-4)N