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Soil water content effects on net ecosystem CO2 exchange and actual evapotranspiration in a Mediterranean semiarid savanna of Central Chile

  • Meza, Francisco J.
  • Montes, Carlo
  • Bravo-Martínez, Felipe
  • Serrano-Ortiz, Penélope
  • Kowalski, Andrew S.
Biosphere-atmosphere water and carbon fluxes depend on ecosystem structure, and their magnitudes and seasonal behavior are driven by environmental and biological factors. We studied the seasonal behavior of net ecosystem CO2 exchange (NEE), Gross Primary Productivity (GPP), Ecosystem Respiration (RE), and actual evapotranspiration (ETa) obtained by eddy covariance measurements during two years in a Mediterranean Acacia savanna ecosystem (Acacia caven) in Central Chile. The annual carbon balance was −53 g C m−2 in 2011 and −111 g C m−2 in 2012, showing that the ecosystem acts as a net sink of CO2, notwithstanding water limitations on photosynthesis observed in this particularly dry period. Total annual ETa was of 128 mm in 2011 and 139 mm in 2012. Both NEE and ETa exhibited strong seasonality with peak values recorded in the winter season (July to September), as a result of ecosystem phenology, soil water content and rainfall occurrence. Consequently, the maximum carbon assimilation rate occurred in wintertime. Results show that soil water content is a major driver of GPP and RE, defining their seasonal patterns and the annual carbon assimilation capacity of the ecosystem, and also modulating the effect that solar radiation and air temperature have on NEE components at shorter time scales., This work was funded by FONDECYT projects 1120713 and 1170429, a grant from the Inter-American Institute for Global Change Research (IAI) [grant number CRN3056], which is supported by the US National Science Foundation [grant number GEO-1128040], and the Spanish Ministry of Economy and Competitiveness project GEI Spain (CGL2014-52838-C2-1-R), including ERDF founds. F. Bravo-Martínez is grateful to CONICYT for the grants “Formación de Capital Humano Avanzado-2009′′, “Beca de Apoyo al término de la tesis doctoral-2012′′, and CORFO INNOVA Grant N° 09CN14-5704. We thank to Enrique Pérez Sanchez-Cañete and Borja Ruíz- Reverter for technical support. We also thank “CODELCO–División Andina” for use of the site. C. Montes acknowledges the NASA Postdoctoral Program and to Universities Space Research Association.

Structure and temporal dynamics of a seaweed assemblage dominated by the invasive lineage 2 of Asparagopsis taxiformis (Bonnemaisoniaceae, Rhodophyta) in the Alboran Sea

  • Zanolla, Marianela
  • Carmona, R.
  • Rosa Álamos, Julio Carlos De La
  • Altamirano, María
Asparagopsis taxiformis is a rhodophycean species composed of six genetic lineages, one of which is considered a relevant invasive component of Mediterranean flora. This study describes seasonal changes in the structure and biomass of the native community associated with A. taxiformis on the coast of Granada (southern Spain). The native community was represented by 18 Rhodophyta, 3 Chlorophyta, and 4 Ochrophyta species. Biomass was dominated by A. taxiformis and Halopteris filicina. In January, A. taxiformis represented only 16% of the whole community biomass, but 2 months later, more than 90% of the community biomass was formed by the invasive species. During the study period, species richness, the Shannon diversity index, and species evenness showed low and generally stable values. Given that A. taxiformis gametophytes are present throughout the year, they likely pose a constant stress to the development of the native community. This survey provides baseline information on the macroalgal community structure, which may be useful to further studies on the actual impact of the invasive lineage of A. taxiformis, This work was funded by the projects CGL2008/01549/ BOS (Ministerio de Ciencia e Innovación, Spain), P09- RNM-5187 (Consejería de Innovación, Ciencia y Empresa, Junta de Andalucía, Spain), 806/5.03.3553 and 806/5.03.3673 (Instituto de Estudios Ceutíes, Spain). It was developed in the framework of the Research Collaboration Agreement between Consejería de Medio Ambiente y Ordenación del Territorio de la Junta de Andalucía and the University of Málaga.

Resultados preliminares tras 50 años de docencia.

  • Prieto, Alberto
Conferencia pronunciada en las XXIV Jornadas de la Asociación de Enseñantes Universitarios de la Informática (JENUI), Universita Oberta de Catalunya, con motivo de la entrega del Premio a la Calidad e Innovación Docente (2018) al autor de la conferencia., Se describe la evolución de las metodologías docente en las universidades y los problemas actuales a superar., Asociación de Enseñantes Universitarios de la Informática (AENUI) http://www.aenui.net/

Search for the Decay of the Higgs Boson to Charm Quarks with the ATLAS Experiment

  • Aguilar-Saavedra, Juan Antonio
  • Atlas Collaboration, /
A direct search for the standard model Higgs boson decaying to a pair of charm quarks is presented. Associated production of the Higgs and Z bosons, in the decay mode ZH→ℓ+ℓ-cc¯ is studied. A data set with an integrated luminosity of 36.1  fb-1 of pp collisions at s=13TeV recorded by the ATLAS experiment at the LHC is used. The H→cc¯ signature is identified using charm-tagging algorithms. The observed (expected) upper limit on σ(pp→ZH)×B(H→cc¯) is 2.7 (3.9-1.1+2.1) pb at the 95% confidence level for a Higgs boson mass of 125 GeV, while the standard model value is 26 fb., Funded by SCOAP3

Car following: Comparing distance-oriented vs. inertia-oriented driving techniques

  • Blanch Micó, Mª Teresa
  • Lucas Alba, Antonio
  • Bellés Rivera, Teresa
  • Ferruz Gracia, Ana Mª
  • Melchor Galán, Óscar M.
  • Delgado Pastor, Luis Carlos
  • Ruíz Jiménez, Francisco
  • Chóliz Montañés, Mariano
The rationale behind most car-following (CF) models is the possibility to appraise and formalize how drivers naturally follow each other. Characterizing and parametrizing Normative Driving Behavior (NDB) became major goals, especially during the last 25 years. Most CF models assumed driver propensity for constant, safe distance is axiomatic. This paper challenges the idea of safety distance as the main parameter defining a unique (or natural) NDB. Instead, it states drivers can adapt to reactive and proactive car following. Drawing on recent CF models close to the Nagoya paradigm and on other phenomena (e.g., wave movement in Nature), we conceived car following by Driving to keep Inertia (DI) as an alternative to Driving to keep Distance (DD). On a driving simulator, three studies (N ¼ 113) based on a repeated-measures experimental design explored the efficiency of these elementary techniques by measuring individual driver performance (e.g., accelerations, decelerations, average speed, distance to leader). Drivers easily grasped and applied either technique and easily switched back and forth between the two. As an overall indicator, all the studies revealed DI trips use about 20% less fuel than DD trips do., Support came from Fundación Universitaria Antonio Gargallo y Obra Social Ibercaja, Spain (grant 2015/B011)

Uso didáctico de la poesía en el aula de español como lengua extranjera. Lectura y aplicación de un poema de Eloy Sánchez Rosillo al nivel avanzado de EEOOII, Didactic use of poetry in the classroom of Spanish as a foreign language. Reading and application of a poem by Eloy Sánchez Rosillo to the advanced level of Official Schools of Languages

  • Sánchez García, María Remedios
  • Lanseros Sánchez, Raquel
El presente trabajo es una propuesta didáctica para la aplicación de la poesía al aula de español como lengua extranjera en el nivel avanzado de las EEOOII. Se pretende que el alumnado desarrolle su competencia lectora, su capacidad de análisis literario y su conocimiento de la cultura española, a la vez que se familiarizan con la poesía contemporánea. Para ello, hemos seleccionado un poema de Eloy Sánchez Rosillo cuya temática aborda la construcción de un poema, a fin de brindar una oportunidad de reflexión sobre la escritura y ejercicio de la destreza de expresión escrita. A partir del poema seleccionado, se propone un conjunto de actividades que busca desarrollar y potenciar las cuatro destrezas comunicativas, así como la interpretación del lenguaje poético y su multiplicidad de significación. Asimismo, se propone una serie de instrumentos de evaluación que puedan dar cuenta del rendimiento global del alumnado., The present work is a didactic proposal for the application of poetry to the classroom of Spanish as a foreign language in the advanced level of the EEOOII. Students are expected to develop their reading skills, literary analysis skills and knowledge of Spanish culture, while becoming familiar with contemporary poetry. For that purpose, we have selected a poem by Eloy Sánchez Rosillo whose theme addresses the construction of a poem, in order to provide an opportunity for reflection on writing and exercising the written expression skill. From the selected poem, a set of activities is proposed that seeks to develop and enhance the four communicative skills, as well as the interpretation of poetic language and its multiplicity of meaning. Likewise, a series of evaluation instruments are proposed that can give an account of the overall performance of students

Sampling rare events across dynamical phase transitions

  • Pérez Espigares, Carlos
  • Hurtado Fernández, Pablo Ignacio
Interacting particle systems with many degrees of freedom may undergo phase transitions to sustain atypical fluctuations of dynamical observables such as the current or the activity. In some cases, this leads to symmetry-broken space-time trajectories which enhance the probability of such events due to the emergence of ordered structures. Despite their conceptual and practical importance, these dynamical phase transitions (DPTs) at the trajectory level are difficult to characterize due to the low probability of their occurrence. However, during the last decade, advanced computational techniques have been developed to measure rare events in simulations of many-particle systems that allow the direct observation and characterization of these DPTs. Here we review the application of a particular rare-event simulation technique, based on cloning Monte Carlo methods, to characterize DPTs in paradigmatic stochastic lattice gases. In particular, we describe in detail some tricks and tips of the trade, paying special attention to the measurement of order parameters capturing the physics of the different DPTs, as well as to the finite-size effects (both in the system size and in the number of clones) that affect the measurements. Overall, we provide a consistent picture of the phenomenology associated with DPTs and their measurement., Ministerio Español MINECO proyecto (No. FIS2017-84256-P). Consejería de Conocimiento, Investigación y Universidad, Junta de Andalucía and European Regional Development Fund (ERDF), ref. SOMM17/6105/UGR. C.P.E. acknowledges the funding received from the European Union’s Horizon 2020 re-search and innovation programme under the Marie Sklodowska-Curie Cofund Programme Athenea3I GrantAgreement No. 754446.

El proceso del perdón en las relaciones íntimas: consecuencias para el bienestar

  • Beltrán Morillas, Ana María
Desde tiempos remotos, el acto de perdonar parece haber constituido un gran aliciente para disciplinas como la filosofía y la teología, siendo prácticamente reciente el interés por abordarse desde una aproximación más psicológica; quizá debido al auge de la Psicología Positiva, desde donde se ha reflexionado acerca de sus efectos positivos sobre la satisfacción y el bienestar (Prieto-Ursúa et al., 2012). Así, cada vez han sido más las investigaciones que han indagado sobre los antecedentes y consecuencias psicológicas de este proceso en diferentes ámbitos (Strelan & Covic, 2006), prestándose especial atención a su naturaleza psicosocial (e.g., Baumeister, Exline, & Sommer, 1998). Considerando particularmente el contexto de la pareja, se infiere que, dado que las relaciones íntimas son una de las mayores fuentes de felicidad en la vida del individuo (Gunderson & Ferrari, 2008), se halla muy dificultoso lidiar con una transgresión de la persona a quien se ama (Gerlach, Agroskin, & Denissen, 2012). Máxime, si la transgresión se percibe con severidad (Fincham, Jackson, & Beach, 2005), lo que podría acabar deteriorando de manera significativa el equilibrio o la estabilidad de la relación (Dillow, 2016). Bajo estas circunstancias, el perdón se estima como un medio de sanación para los miembros de la pareja, y en especial para la parte ofendida, quien puede determinar si desea restaurar o restablecer la relación con la parte transgresora., Tesis Univ. Granada., Ideología sexista y diferencias de poder en el origen y mantenimiento del acoso sexual (Ref. PSI2011-29720) (MINECO/AEI/FEDER/UE), Análisis psicosocial del acoso sexual: Nuevas formas y nuevos contextos (Ref. PSI2014-59200R) (MINECO/AEI/FEDER/UE), Nuevas formas de violencia de género: Factores de riesgo y protectores para el bienestar psicosocial (Ref. PSI2017-84703R) (MINECO/AEI/FEDER/UE).

Explanatory model of violent behaviours, self-concept and empathy in schoolchildren. Structural equations analysis

  • Castro Sánchez, Manuel
  • Zurita Ortega, Félix
  • Ruiz Rico Ruiz, Gerardo
  • Chacón-Cuberos, Ramón
The increased visibility of bullying cases has led the scientific community to be more interested in analysing the factors affecting these behaviours in order to reduce bullying cases and their negative consequences. The aim of this study was to define and contrast an explanatory model that makes it possible to analyse the relationships between self-concept, empathy and violent behaviours in schoolchildren through structural equation analysis. The sample of this study is made up of 734 schoolchildren from the province of Granada (Spain), both male and female, aged between 10 and 12, and it consists of analysing self-concept (AF-5), empathy levels (TECA) and violent behaviour at schools (ECV). A structural equation model was performed and successfully adjusted (χ2 = 563.203; DF = 59; p < 0.001; CFI = 0.943; NFI = 0.937; IFI = 0.943; RMSEA = 0.076). A positive and direct relationship between self-concept and cognitive empathy has been found; manifest aggression is negatively related to self-concept. Similarly, affective empathy has a negative relationship with relational aggression. The main conclusions of this study are that the levels of self-concept and empathy represent protective factors against the development of violent and victimisation behaviours in schoolchildren.

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