As a result of the technological advancements in our society, the number of students enrolling in Computer Science and related courses continues to rise. Programming is regarded as a difficult ...subject to learn, and as the size of classes and the number of students enrolled in online courses continues to increase, providing individualized support to determine where the difficulties of a student lie may appear impossible, resulting in frustration, lack of motivation, and an increase in dropout rates. Chatbots can mitigate this problem as it can provide simultaneous support to multiple students 24 hours a day, seven days a week, and by allowing introverted students to express questions more comfortably. This paper proposes the implementation of a chatbot denominated Pyo aiming to provide assistance to novice programmers. It was evaluated how students enrolled in an online introductory programming course interacted with Pyo in order to draw conclusions about the effectiveness of the chatbot's features. The results indicate that Pyo facilitates student learning; however, more straightforward explanations of its functionalities were requested.
Abies pinsapo (Boiss.) is a relict, endemic fir species, that growths at Sierra de las Nieves and Sierra Bermeja (Málaga), and Sierra de Grazalema (Cádiz), in the western part of the Betic Mountain ...Range (S. of the Iberian peninsula). It is currently distributed within 1000-1700 m a.s.l., occupying about 2000 Ha only, in north-facing slopes, where local geographic and orographic determinants allows for very high precipitation values (from 1000 up to 3000 mm). In its basal altitudinal range, Abies pinsapo forms mixed forests with several Quercus species (Q. rotundifolia, Q. faginea, and even Q. suber). At higher altitude, it forms dense and pure stands, the "pinsapares", that resemble, in physiognomic terms, temperate-boreal conifer forests, despite being within a mediterraneantype climate region. The biogeographic singularity of Abies pinsapo, shared with that of the rest of circum-mediterranean fir species, resulted from an extraordinary concatenation of events, including the collision of the Eurasian and African tectonic plaques and the formation of coastal mountain ranges around the Mediterranean basin, the progressive aridification of the climate that took place from the mid-Miocene, the fluctuation between glacial a inter-glacial periods during the Quaternary, and the existence of local refuges that enabled its survival as a relict species. As a result of their biogeographic singularity, the "pinsapares" represent biodiversity islands, holding many associated endemic plant and animal species. They also constitute a specially suitable model to assess for early-warning signs of the global warming. El pinsapo (Abies pinsapo, Boiss.) es un abeto, relicto del Terciario, endémico de tres sierras de las provincias de Málaga (Sierra de las Nieves, Sierra Bermeja) y Cádiz (Sierra de Grazalema), en la zona occidental de las Cordilleras Béticas. Se distribuye entre 1000 y 1700 m de altitud, ocupando poco más de 2000 Ha, siempre en laderas umbrías con orientación norte, donde recibe abundante precipitación orográfica (desde 1000 hasta incluso 3000 mm anuales). En la franja basal de su distribución forma bosques mixtos con encinas, quejigos e incluso alcornoques; mientras que, en bandas altitudinales más elevadas, tiende a formar bosques puros, los pinsapares, cuya fisiognomía asemeja la de un bosque de coníferas templado-boreal, a pesar de encontrarse inmersos en una región de clima Mediterráneo. La excepcionalidad y singularidad biogeográfica del pinsapo, compartida con la del resto del grupo de abetos circum-mediterráneos, deriva de una extraordinaria concatenación de eventos que incluye el levantamiento de cordilleras costeras con el choque de las placas tectónicas eurosiberiana y africana, la progresiva aridificación del clima en la cuenca mediterránea que se inicia a mediados del Mioceno, seguida de la alternancia de periodos glaciares y de calentamiento climático interglaciar durante el Cuaternario; y de la existencia, entre tantos avatares que jugaban en su contra, de refugios locales que permitieron su pervivencia como especie relicta. Como resultado de su singularidad biogeográfica, los pinsapares constituyen islas de biodiversidad, con numerosas especies asociadas, tanto de plantas como de animales, muchas de ellas también endémicas. Asimismo, representan un modelo excepcional para el seguimiento de síntomas tempranos del calentamiento climático.
The worldwide phenomenon of shrub encroachment in grass-dominated dryland ecosystems is commonly associated with desertification. Studies of the purported desertification effects associated with ...shrub encroachment are often restricted to relatively few study areas, and document a narrow range of possible impacts upon biota and ecosystem processes. We conducted a study in degraded Mediterranean grasslands dominated by Stipa tenacissima to simultaneously evaluate the effects of shrub encroachment on the structure and composition of multiple biotic community components, and on various indicators of ecosystem function. Shrub encroachment enhanced vascular plant richness, biomass of fungi, actinomycetes and other bacteria, and was linked with greater soil fertility and N mineralization rates. While shrub encroachment may be a widespread phenomenon in drylands, an interpretation that this is an expression of desertification is not universal. Our results suggest that shrub establishment may be an important step in the reversal of desertification processes in the Mediterranean region.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Systemic lupus erythematosus (SLE) is a common systemic autoimmune disease with a complex genetic inheritance. Genome-wide association studies (GWAS) have significantly increased the number of ...significant loci associated with SLE risk. To date, however, established loci account for less than 30% of the disease heritability and additional risk variants have yet to be identified. Here we performed a GWAS followed by a meta-analysis to identify new genome-wide significant loci for SLE.
We genotyped a cohort of 907 patients with SLE (cases) and 1524 healthy controls from Spain and performed imputation using the 1000 Genomes reference data. We tested for association using logistic regression with correction for the principal components of variation. Meta-analysis of the association results was subsequently performed on 7,110,321 variants using genetic data from a large cohort of 4036 patients with SLE and 6959 controls of Northern European ancestry. Genetic association was also tested at the pathway level after removing the effect of known risk loci using PASCAL software.
We identified five new loci associated with SLE at the genome-wide level of significance (p < 5 × 10
): GRB2, SMYD3, ST8SIA4, LAT2 and ARHGAP27. Pathway analysis revealed several biological processes significantly associated with SLE risk: B cell receptor signaling (p = 5.28 × 10
), CTLA4 co-stimulation during T cell activation (p = 3.06 × 10
), interleukin-4 signaling (p = 3.97 × 10
) and cell surface interactions at the vascular wall (p = 4.63 × 10
).
Our results identify five novel loci for SLE susceptibility, and biologic pathways associated via multiple low-effect-size loci.
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