The role of pressure on the magnetism of bilayer graphene

We study the effect of pressure on the localized magnetic moments induced by vacancies in bilayer graphene in the presence of topological defects breaking the bipartite nature of the lattice. By using a mean-field Hubbard model we address the two inequivalent types of vacancies that appear in the Bernal stacking bilayer graphene. We find that by applying pressure in the direction perpendicular to the layers the critical value of the Hubbard interaction needed to polarize the system decreases. The effect is particularly enhanced for one type of vacancies, and admits straightforward generalization to multilayer graphene in Bernal stacking and graphite. The present results clearly demonstrate that the magnetic behavior of multilayer graphene can be affected by mechanical transverse deformation

Titanato de circonio: estabilidad termodinámica y expansión térmica

El titanato de circonio es un compuesto muy usado en aplicaciones electrocerámicas, aunque también se han descrito aplicaciones en el campo de la catálisis y de los sensores. Dada la anisotropía en la expansión térmica cristalográfica de este compuesto, podría ser planteado como constituyente de componentes estructurales. En general, para asegurar la integridad estructural y la homogeneidad microestructural de una pieza cerámica, es preciso utilizar velocidades de enfriamiento desde la temperatura de fabricación relativamente bajas. Este requerimiento tiene una importancia fundamental en el titanato de circonio, ya que pequeñas variaciones en la composición y en la velocidad de enfriamiento, producen variaciones significativas tanto en la distribución de fases como en la expansión térmica. En este trabajo se revisan los trabajos existentes sobre la estabilidad del titanato de circonio dentro de los sistemas ZrO2-TiO2 y ZrO2-TiO2-Y2O3. Se describen las principales discrepancias acerca de las fases compatibles existentes en la bibliografía actual y se discute el posible origen de estas discrepancias. Asimismo, se revisan los datos existentes sobre la expansión térmica cristalográfica de este compuesto.Peer reviewe

A ringed pole-on outflow from DO Tauri revealed by ALMA

We present new ALMA Band 6 observations including the CO (2-1) line and 1.3 mmcontinuum emission from the surroundings of the young stellar object DO Tauri. TheALMA CO molecular data show three different series of rings at different radial ve-locities. These rings have radii around 220 au and 800 au. We make individual fits tothe rings and note that their centers are aligned with DO Tauri and its optical high-velocity jet. In addition, we notice that the velocity of these structures increases withthe separation from the young star. We discuss the data under the hypothesis that therings represent velocity cuts through three outflowing shells that are possibly drivenby a wide-angle wind, dragging the environment material along a direction close to theline of sight (i= 19◦). We estimate the dynamical ages, the mass, the momentum andthe energy of each individual outflow shell and those of the whole outflow. The resultsare in agreement with those found in outflows from Class II sources. We make a roughestimate for the size of the jet/wind launching region, which needs to be of.15 au.We report the physical characteristics of DO Tauri?s disk continuum emission (almostface-on and with a projected major axis in the north-south direction) and its velocitygradient orientation (north-south), indicative of disk rotation for a 1-2 Mcentral star.Finally we show an HST [SII] image of the optical jet and report a measurement of itsorientation in the plane of the sky.Fil: Fernandez Lopez, Manuel. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Argentino de Radioastronomía. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Argentino de Radioastronomía; ArgentinaFil: Zapata Gonzalez, Luis Alberto. Universidad Nacional Autonoma de Mexico. Instituto de Astronomia; MéxicoFil: Rodríguez, Luis F.. Universidad Nacional Autonoma de Mexico. Instituto de Astronomia; MéxicoFil: Vazzano, María Mercedes. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Argentino de Radioastronomía. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Argentino de Radioastronomía; ArgentinaFil: Guzman, Andrés E.. National Astronomical Observatory Of Japan; JapónFil: López, Rosario. Universidad Autónoma de Barcelona. Facultad de Física. Departamento Astronomía y Meteorología; Españ

Temporal Bacteriostatic Effect and Growth Factor Loss in Equine Platelet Components and Plasma Cultured with Methicillin-Sensitive and Methicillin-Resistant Staphylococcus aureus

The aims were (1) to evaluate the bacteriostatic effect of platelet-rich plasma (PRP), platelet-rich gel (PRG), leukocyte-poor plasma (LPP), leukocyte-poor gel (LPG), plasma, and heat-inactivated plasma (IP) on both methicillin-sensitive Staphylococcus aureus (MSSA) and methicillin-resistant Staphylococcus aureus (MRSA) over a period of 24 h; (2) to determine and to compare the concentrations and degradation over time of platelet factor 4 (PF-4), transforming growth factor beta 1 (TGF-β1), and platelet-derived growth factor isoform BB (PDGF-BB); and (3) to identify any correlations between MSSA and MRSA growth and either the cellular, PF-4, TGF-β1, or PDGF-BB concentrations in the blood components. PRP and its byproducts from 18 horses were obtained by the tube method. All blood components were cultured with either MSSA or MRSA. Bacterial growth, PF-4, TGF-β1, and PDGF-BB were determined at 6 h and 24 h. At six hours, bacterial growth was significantly inhibited by all blood components, with the exception of IP. MSSA was more sensitive to the treatments than MRSA. At 24 hours, bacterial growth was significantly higher in IP. MRSA bacterial growth was significantly higher in PRP, LPP, and plasma when compared to MSSA. Growth factor concentrations were not significantly affected by bacteria

A Review of the Studies and Interactions of Pseudomonas syringae

Wheat is affected by some pathovars of Pseudomonas syringae and by other Pseudomonas species. Of these, P. syringae pv. syringae is the major one responsible for reduction. Recent studies have been made to characterize and identify the pathogen and to determine its aggressiveness and the pattern of colonization in seed and its effects on seed yield, yield components, and source-sink relationships during postanthesis. It was found that the reduction in the aerial biomass production is the best way to evaluate the aggressiveness of this bacterium, and the spray inoculation is good tool to make evaluations at seedling stage. The characterization of bacteria fingerprintings with molecular markers such as RAPD-PCR, ERIC, and REP-PCR is available. Genomic evolution has been elucidated with next-generation genome sequencing. Also, the colonization pattern shows that, early on, microcolonies are frequently detected in the aleurone layer, later in the endosperm and finally close to the crease and even in some cells of the embryo itself. In the wheat cultivars Seri M82 and Rebeca F2000 seed yield and its components are negatively affected. In general, P. syringae pv. syringae reduces the plant height, seed yield, and yield components, as well as the growth of most organs. When this bacterium attacks, the stems are the predominant sink organs and the leaf laminae and panicles are the predominant source organs

Identification of the water stress level in olive trees during pit hardening using the trunk growth rate indicator.

Water scarcity is generating an increasing interest in deficit irrigation scheduling. The trunk diameter fluctuations are daily cycles that have been suggested as tools for irrigation scheduling. The trunk growth rate (TGR) was suggested as the best indicator for olive trees during pit hardening. The aim of this work is to clarify how the TGR could be used to identify water stress levels. The experiment was performed during the 2017 season, in a commercial, super-high-density orchard in Carmona (Seville, Spain). Four different irrigation treatments were performed according to midday stem water potential values and TGR. The data obtained were very variable and both indicators presented a wide range of water status throughout the season. The maximum trunk diameter data clearly showed the pattern of the trees water status but the comparison between treatments and the identification of the water stress level was not possible. The average TGR was linked to the midday stem water potential, but with a minimum amount of data. Irrigation scheduling based on the average TGR was difficult because of the great increases in some daily TGR values. For clarity, the pool of data was grouped by midday stem water potential. These water stress levels were characterized using the weekly frequency of TGR values. The increase of water stress reduced the frequency of values between -0.1 and 0.3mm day-1 from 60% to less than 25%. Moderate water stress levels increased the percentage of values lower than -0.3mm day-1 from 7% to 37%. The most severe water stress conditions increased the TGR values between -0.3 and -0.1mm day-1 from 16% up to 22%.IRNASINSTITUTO DE LA GRASACSI

Estilos de trabajo e inteligencias múltiples

El objetivo del trabajo es determinarla validez yflabilidad del modelo dejos estilos de trabajo, fundamentado en la teoría de las Inteligencias Múltiples (IM). Primero, se analizan los componentes de dicha teoría y su incidencia en el curriculum escolar. En segundo lugar, se estudia el procedimiento de evaluación. Además, se presentan los resultados del estudio empírico realizado con una muestra de 237 alumnos pertenecientes a Educación Infantil y Primaria, escolarizados en centros públicos y privados de la Región de Murcia. Del estudio realizado se desprende que los estilos están asociados a las diferentes inteligencias; además, el inventario de estilos de trabajo arroja una validez y fiabilidad altamente consistente.________________________________ The objective of this work is to determinate the validity and reliability of the model of work styles, as set out In the theory of Multiple Intelligences (MI). First, we analyze the components of this theory and their Incidence in the school curriculum. Second, we study the evaluation procedure. Additionally, we present the results of an empirical study carried out with a sample of 237 students in public and private nursery and primary schools in the province of Murcia, Spain. The study carried out reveals that the styles are associated with the different Intelligences. Furthermore, the inventory of styles shows a highly consistent validity and reliability

Bibliografía [Cuadernos del Instituto Antonio de Nebrija de estudios sobre la Universidad. 2006, nº 9]

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Phase evolution in reaction sintered zirconium titanate based materials

11 páginas, 17 figuras.-- El pdf del artículo es la versión post-print.Zirconium titanate materials are proposed for structural components for which fully reacted and relatively large pieces are required. In this work the phase evolution in slip cast compacts constituted by equimolar mixtures of TiO2 and ZrO2 stabilized with 3 mol% of Y2O3 at high temperature is studied, to establish the basis to design suitable thermal treatments for ZrO2(Y2O3)–TiO2 materials. The temperatures at which the processes involved in the reaction sintering occurred were identified by constant heating rate experiments. Phase and microstructure analyses have been performed on specimens treated at the identified temperatures and air quenched. Then the adequate temperature range to get fully reacted and dense materials has been deduced. Materials treated at 1500 ◦C to 2 h were constituted by Zr5Ti7O24 as major phase, a solid solution of TiO2 and Y2O3 in c-ZrO2 as secondary phase and a ZrO2–TiO2–Y2O3 non-stoichiometric compound with pyrochlore structure as minor phase. Pyrochlore was demonstrated to be a metastable phase at 1500 ◦C.This work has been supported by the Spanish Ministry of Education and Science under contracts MEC MAT2006- 13480 C02-01 and MAT2007-64486 C07-02. E. López-López acknowledges to Community of Madrid (Spain) and European Social Fund for economical support by CPI/0552/2007 contract.Peer reviewe

Escape behavior in gravid and non-gravid females of Gonatodes albogularis (Squamata: Sphaerodactylidae)

Comportamento de fuga em fêmeas grávidas e não-grávidas de Gonatodes albogularis (Squamata: Sphaerodactylidae). Modelos teóricos de relações predador-presa descrevem balanços entre custos de fuga (energéticos e de outros tipos), efciência do comportamento de fuga e risco de predação. Esses modelos preveem que um animal escapará quando o custo esperado em termos de sucesso reprodutivo devido ao risco de predação quando for igual ao custo de fuga ou quando o sucesso reprodutivo após o encontro for maximizado, dependendo do modelo. Nesse cenário, demonstrou-se que diversas variáveis individuais e ecológicas afetam os padrões de fuga, mas o efeito do status reprodutivo foi estudado em poucas espécies. Nós avaliamos diferenças no comportamento de fuga entre fêmeas grávidas e não-grávidas de Gonatodes albogularis. Os lagartos foram estudados aplicando-se um método de procura livre ao longo de transectos independentes. Para cada fêmea, determinamos o status reprodutivo como grávida ou não-grávida e registramos diversas variáveis relacionadas ao comportamento de fuga. Desenvolvemos uma análise discriminante para verifcar se o estado dos indivíduos afetavam o comportamento de fuga. Nossos resultados mostram que as variáveis distância percorrida na fuga, distância fnal e distância para o refúgio diferem entre fêmeas grávidas e não-grávidas. Essas descobertas sustentam previsões baseadas em risco e custo, mas não sustentam modelos de distância de início de fuga. Tais diferenças poderiam estar relacionadas como um processo conhecido como compensação comportamental, por meio do qual alguns indivíduos (as fêmeas grávidas, no nosso caso) modifcam seu comportamento para compensar risco de predação. Estudos adicionais são necessários para verifcar se a compensação comportamental pode ser explicada em termos de processos adaptativos em G. albogularis.Escape behavior in gravid and non-gravid females of Gonatodes albogularis (Squamata: Sphaerodactylidae). Theoretical models of predator-prey relationships describe tradeoffs between energetic and other costs of escape, effectiveness of escape behavior, and predation risk. These models predict that an animal will fee when the expected ftness cost due to risk of predation becomes equal to the the cost of the escape or post-encounter ftness is maximized, depending on the model. In this framework, several individual and ecological variables have been shown to affect escape patterns, but the effect of reproductive status has been studied in few species. We assess differences in escape behavior between gravid and non-gravid females of Gonatodes albogularis. Lizards were surveyed by applying a free search method along independent transects. For each lizard, we determined reproductive status as gravid or non-gravid and recorded several variables related to escape behavior. We made a discriminant function analysis to see whether the state of individuals affect escape behavior. Our results show that the escape variables distance fed, the fnal distance and the distance to refuge differ between gravid and non-gravid females. These fndings support predictions based on risk and cost, but do not support models of fight initiation distance. Such differences could be related to a physiological process known as behavioral compensation, through which some individuals (gravid females in our case) modify their behavior to offset predation risk. Further studies are needed to see if behavioral compensation can be explained in terms of adaptive processes in G. albogularis