Surges and Si IV bursts in the solar atmosphere. Understanding IRIS and SST observations through RMHD experiments

Surges often appear as a result of the emergence of magnetized plasma from the solar interior. Traditionally, they are observed in chromospheric lines such as H$\alpha$ 6563 \AA and Ca II 8542 \AA. However, whether there is a response to the surge appearance and evolution in the Si IV lines or, in fact, in many other transition region lines has not been studied. In this paper we analyze a simultaneous episode of an H$\alpha$ surge and a Si IV burst that occurred on 2016 September 03 in active region AR12585. To that end, we use coordinated observations from the Interface Region Imaging Spectrograph (IRIS) and the Swedish 1-m Solar Telescope (SST). For the first time, we report emission of Si IV within the surge, finding profiles that are brighter and broader than the average. Furthermore, the brightest Si IV patches within the domain of the surge are located mainly near its footpoints. To understand the relation between the surges and the emission in transition region lines like Si IV, we have carried out 2.5D radiative MHD (RMHD) experiments of magnetic flux emergence episodes using the Bifrost code and including the non-equilibrium ionization of silicon. Through spectral synthesis we explain several features of the observations. We show that the presence of Si IV emission patches within the surge, their location near the surge footpoints and various observed spectral features are a natural consequence of the emergence of magnetized plasma from the interior to the atmosphere and the ensuing reconnection processes.Comment: 13 pages, 8 figures. The Astrophysical Journal (Accepted

Hybrid algorithm with perturbations for total asymptotically non-expansive mappings in CAT(0) space

In this paper, we establish strong and Δ-convergence theorems of the modified hybrid-CR three steps iteration with perturbations for total asymptotically non-expansive mapping in CAT(0) spaces. Our results improve and extend the corresponding results from the current literature. We also provide three examples to illustrate the convergence behaviour of the proposed algorithm and numerically compare the convergence of the proposed iteration scheme with the existing schemes

Design of a checklist for evaluating language learning websites

This paper focuses on the creation of an evaluation tool which provides a thorough assessment of EFL learning websites. After analysing different frameworks for assessing EFL sites, we will define a clear model based on a set of criteria committed to assess EFL learning websites. Finally, we will propose our own evaluation checklist for surveying the nature of such sites comprising some key items for analysis such as multimedia, interactivity, educational content and more especially those related communicative aspects included such as computer mediated communication (CMM).El objetivo del presente trabajo es la creación de una herramienta que permita una evaluación exhaustiva de páginas web para el aprendizaje del inglés como lengua extranjera. Después de un profundo análisis de las distintas tendencias a la hora de evaluar sitios web, nos centraremos en definir un modelo claro basado en un conjunto de criterios que permita evaluar distintos sitios web para el aprendizaje del inglés como lengua extranjera, para finalmente presentar nuestra propia propuesta de análisis de los elementos clave de una web diseñada para tal fin en la que se incluyen una serie de ítems clave tales como el uso de multimedia, interactividad, contenido educativo y en especial, aquellos estrechamente relacionados con aspectos comunicativos tales como la comunicación a través del ordenador

El diseño de una lista de comprobación para evaluar sitios web para el aprendizaje de la lengua extranjera

This paper focuses on the creation of an evaluation tool which provides a thorough assessment of EFL learning websites. After analysing different frameworks for assessing EFL sites, we will define a clear model based on a set of criteria committed to assess EFL learning websites. Finally, we will propose our own evaluation checklist for surveying the nature of such sites comprising some key items for analysis such as multimedia, interactivity, educational content and more especially those related communicative aspects included such as computer mediated communication (CMM).El objetivo del presente trabajo es la creación de una herramienta que permita una evaluación exhaustiva de páginas web para el aprendizaje del inglés como lengua extranjera. Después de un profundo análisis de las distintas tendencias a la hora de evaluar sitios web, nos centraremos en definir un modelo claro basado en un conjunto de criterios que permita evaluar distintos sitios web para el aprendizaje del inglés como lengua extranjera, para finalmente presentar nuestra propia propuesta de análisis de los elementos clave de una web diseñada para tal fin en la que se incluyen una serie de ítems clave tales como el uso de multimedia, interactividad, contenido educativo y en especial, aquellos estrechamente relacionados con aspectos comunicativos tales como la comunicación a través del ordenador

Cladobotryum mycophilum as Potential Biocontrol Agent

A study was conducted to explore the efficacy of potential biocontrol agent Cladobotryum mycophilum against different phytopathogenic fungi. The growth rates of 24 isolates of C. mycophilum were determined, and their antagonistic activity was analysed in vitro and in vivo against Botrytis cinerea, Fusarium oxysporum f. sp. radicis-lycopersici, Fusarium oxysporum f.sp. cucumerinum, Fusarium solani, Phytophthora parasitica, Phytophthora capsici, Pythium aphanidermatum and Mycosphaerella melonis. Most isolates grow rapidly, reaching the opposite end of the Petri dish within 72–96 h. Under dual-culture assays, C. mycophilum showed antagonistic activity in vitro against all phytopathogenic fungi tested, with mycelial growth inhibition ranging from 30 to 90% against all the different phytopathogens tested. Similarly, of all the selected isolates, CL60A, CL17A and CL18A significantly (p < 0.05) reduced the disease incidence and severity in the plant assays compared to the controls for the different pathosystems studied. Based on these results, we conclude that C. mycophilum can be considered as a potential biological control agent in agriculture. This is the first study of Cladobotryum mycophilum as a biological control agent for different diseases caused by highly relevant phytopathogens in horticultur

New Insights Into Sunflower (Helianthus annuus L.) FatA and FatB Thioesterases, Their Regulation, Structure and Distribution

Sunflower seeds (Helianthus annuus L.) accumulate large quantities of triacylglycerols (TAG) between 12 and 28 days after flowering (DAF). This is the period of maximal acyl-acyl carrier protein (acyl-ACP) thioesterase activity in vitro, the enzymes that terminate the process of de novo fatty acid synthesis by catalyzing the hydrolysis of the acyl-ACPs synthesized by fatty acid synthase. Fatty acid thioesterases can be classified into two families with distinct substrate specificities, namely FatA and FatB. Here, some new aspects of these enzymes have been studied, assessing how both enzymes contribute to the acyl composition of sunflower oil, not least through the changes in their expression during the process of seed filling. Moreover, the binding pockets of these enzymes were modeled based on new data from plant thioesterases, revealing important differences in their volume and geometry. Finally, the subcellular location of the two enzymes was evaluated and while both possess an N-terminal plastid transit peptide, only in FatB contains a hydrophobic sequence that could potentially serve as a transmembrane domain. Indeed, using in vivo imaging and organelle fractionation, H. annuus thioesterases, HaFatA and HaFatB, appear to be differentially localized in the plastid stroma and membrane envelope, respectively. The divergent roles fulfilled by HaFatA and HaFatB in oil biosynthesis are discussed in the light of our data.España MINECO y FEDER Projects AGL2014- 53537-R y AGL2017-83449-

Asymptotics of Sobolev orthogonal polynomials for symmetrically coherent pairs of measures with compact support

AbstractWe study the strong asymptotics for the sequence of monic polynomials Qn(x), orthogonal with respect to the inner product (f,g)s=∫ f(x)g(x)dμ1(x)+σ ∫ f′(x)g′(x)dμ2(x), σ > 0, with x outside of the support of the measure μ2. We assume that μ1 and μ2 are symmetric and compactly supported measures on R satisfying a coherence condition. As a consequence, the asymptotic behaviour of (Qn,Qn)s and of the zeros of Qn is obtained