Keeping watch over Colombia’s slumbering volcanoes

The Volcanological and Seismological Observatories of Manizales, Pasto and Popayan (Colombian Geological Survey) monitor and study the active volcanoes of Colombia using seismological, geodetic, geochemical and other techniques. Since 2009, permanent GNSS stations have been installed to complement classical geodetic measurements (e.g., tilt, EDM). At the moment, there are a total of 20 GNSS stations installed at Nevado del Ruiz, Cerro Machín, Puracé and Galeras volcanoes. Nevado del Ruiz has remained the most dynamic of the active Colombian volcanoes since its tragic eruption of 13 November 1985. The most significant deformation occurred between 2007 and 2012, when inflation, associated with magma migration and several small to moderate explosive eruptions in 2012 (VEI less or equal to 3), was observed. Galeras has experienced more than 25 moderate Vulcanian eruptions (VEI less or equal to 3) since 1989. In particular, the deformation network detected significant signals associated with magma migration and the extrusion of lava domes in 1991, 2005, 2008 and 2012. Puracé volcano has been the site of more than 10 minor eruptive episodes (VEI=2) in the past century, most recently in 1977. Monitoring of this volcano started in 1994. Unrest at Puracé since that time has been characterized by significant increases in seismic activity but with little or no deformation. We employ GAMIT/GLOBK to process GPS data from the monitoring network with support from the Volcano Disaster Assistance Program (U.S. Geological Survey). Additionally, differential processing is carried out using the commercial package Trimble 4D Control. Preliminary results for 2012 show no significant deformation at Puracé and Galeras volcanoes. On the other hand, the time series from Nevado del Ruiz shows a minor inflation (2-4 cm/yr) associated with the eruptive activity of 2012

Estimation of Carbon Content in the Páramo Ecosystem of Pasa Population, Ambato Canton, Tungurahua Province

The stored carbon content was determined based on a randomized stratified experimental design by type of vegetation; three sampling units of 400 m2 each were installed, from 3600–4100 m.s.n.m., with intervals of 150 m of altitude. The inventory of herbaceous vegetation was taken using the GLORIA method. For the sampling of the aerial biomass and necromass in the plot, circular subplots were constructed, and the samples were collected in 4 quadrants of 0.25 m2, two in each subplot. Samples of 0–20, 20–40 and 40–60 cm were taken from the soil profile, and the percentage of organic carbon in the soil and the apparent density were evaluated. The results indicate a floristic diversity represented by 44 species, 39 of herbaceous vegetation and 5 of tree vegetation. The carbon content stored in aerial biomass returned a value of 83.88 tC⋅ha−1 for herbaceous vegetation and 158.50 tC⋅ha−1 in tree vegetation, and in terms of necromass, returned values of 0.89 tC-ha−1 and 7.40 tC-ha−1, respectively. The carbon stored in the soil at a depth of 20 cm is 111.84 tC- ha−1 for herbaceous vegetation and 122.45 tC-ha−1 for tree vegetation. Keywords: ecosystem, paramo, tree vegetation, carbon, biomass. Resumen Se determinó el contenido de carbono almacenado en base a un diseño experimental estratificado al azar por tipo de vegetación, se instalaron tres unidades de muestreo de 400 m2 cada una, a partir de 3600–4100 m.s.n.m; con intervalos de 150 m de altitud. El inventario de la vegetación herbácea mediante el método GLORIA, Para el muestreo de la biomasa aérea y necromasa en la parcela se anidaron subparcelas circulares, se recolecto las muestras en 4 cuadrantes de 0.25m2 dos en cada subparcela. En el comportamiento suelo se tomaron muestras de 0–20 cm, 20–40 cm y de 40–60 cm, se evaluó el porcentaje de carbono orgánico en el suelo y la densidad aparente. Los resultados indican una diversidad florística representada por 44 especies, 39 de la vegetación herbácea y 5 de la vegetación arbórea. El contenido de carbono almacenado en la biomasa aérea reporto un valor de 83,88 tC⋅ha−1 para vegetación herbácea y de 158,50 tC⋅ha−1 en la vegetación arbórea, en cuanto a necromasa con valores de 0,89 tC-ha−1 y de 7,40 tC-ha−1 respectivamente. El carbono almacenado en el suelo a 20 cm de profundidad es de 111.84 tC-ha−1 la vegetación herbácea y de 122,45 tC-ha−1 para la vegetación arbórea. Palabras clave: ecosistema, paramo, vegetación arbórea, carbono, biomasa

The occurrence and distribution of Xiphinema species (Nematoda : Dorylaimida) in spanish fir woodlands

Une étude comparative a été réalisée en vue de définir l'influence des facteurs édaphiques sur la présence et l'abondance relative de quatre espèces de #Xiphinema observées dans le sol de cinq forêts de sapin (#Abies pinsapo Boiss) du sud de l'Espagne. Les prélèvements ont été effectués de façon saisonnière pendant une année. Afin de relier la présence des espèces avec les caractéristiques de l'habitat et mettre en évidence leur mode de répartition dans les aires étudiées, les méthodes d'analyses univariées (analyse linéaire de la variance) et multivariées (analyses en grappe et de correspondance) ont été utilisées. La répartition de trois des espèces s'est révélée correspondre aux gradients de texture du sol. #X. sphaerocephalum montre ses plus grandes fréquence et abondance relative dans les sols à roche-mère calcaire, mais n'a pas été trouvé sur les péridotites, c'est-à-dire dans des sols plus sableux, préférant les textures plutôt limoneuses. #X. pachtaicum est rencontré dans les sols à texture argileuse plus nettement soumis aux conditions climatiques méditerranéennes. La répartition de #X. diversicaudatum est très nettement liée aux sols acides de texture plus sableuse avec un taux élevé d'argile fine. #X. turcicum, enfin, n'est rencontré que très rarement et en faible nombre, aussi sa répartition dans ces sols demeure-t-elle obscure. (Résumé d'auteur

Instructional Design Methodological Proposal for the Training of Online Content Tutors

With the challenge of change that a teacher faces, the use of educational technologies requires knowledge of instructional design. The teacher plays a prominent role in this process, so it must create educational content, following the principles of an instructional design model. The problem is that not all methodologies include a practical approach where the tutor takes ownership of pedagogical and practical aspects. Therefore, this study proposes an instructional design methodology for online Tutors combining the ADDIE, ASSURE, and PACIE models. In addition, to validate the proposed methodology, an evaluation process is carried out, taking into account the appropriation of the role of tutor of online content and level of use of the LMS tools.     Keywords: instructional design, LMS, online course, E-learnin

Eliminating ambiguities for quantum corrections to strings moving in AdS4×CP3AdS_4\times \mathbb{CP}^3

We apply a physical principle, previously used to eliminate ambiguities in quantum corrections to the 2 dimensional kink, to the case of spinning strings moving in $AdS_4\times \mathbb{CP}^3$, thought of as another kind of two dimensional soliton. We find that this eliminates the ambiguities and selects the result compatible with AdS/CFT, providing a solid foundation for one of the previous calculations, which found agreement. The method can be applied to other classical string "solitons".Comment: 18 pages, latex; references added, comments added at end of section 4, a few words changed; footnote added on page 1

Fish associated with floating drifting objects as a feeding resource for Balearic Shearwaters Puffinus mauretanicus during the breeding season

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The UK Open Textbooks Report

Open Textbooks are openly licensed academic textbooks, where the digital version is available freely, and the print version at highly reduced cost. They are a form of Open Educational Resource (OER) that has seen signi cant impact and success in the USA and Canada. The UK Open Textbook project was funded by the William and Flora Hewlett Foundation with two main aims: firstly to promote the adoption of open textbooks in the UK, and secondly to investigate the transferability of the successful models of adoption to the UK. The project was led by The Open University (UK) OER Hub team in partnership with 2 US based open textbook providers and champions, OpenStax and the Open Textbook Network, and WonkHE and the University of the West of England (UWE). Initial research into the differences between the US and UK context highlighted that textbook use in these two contexts varies considerably and that there was little existing research into UK textbook use. The UK Open Textbook project carried out both an initial literature review and a survey of UK educators during the project. The cost of textbooks is a more significant barrier in the USA, and their usage tends to be more heavily mandated. However, participation costs for UK students are increasing, and textbooks represent a contributing factor. In our 2018 survey with UK Higher Education (HE) educators, it was noted that whilst there is an initial low awareness of OER, respondents had a strong interest in pursuing their adoption. UK Open Textbooks was a project focused on engagement. Through a number of workshops at a range of higher education institutions (HEIs) and targeted promotion at speci c education conferences, the project successfully raised the pro le of open textbooks within the UK. The project focused particularly on STEM subject textbooks and in spite of contextual differences between UK HEIs and their counterparts in North America there was considerable interest and appetite for open textbooks amongst UK academics. This was partly related to cost savings for students and institutions, but more significant factors were the freedom to adapt and develop textbooks. Open textbooks were also viewed as a possible means to counteract the disinterest of commercial publishers in developing books for smaller markets. This report reflects upon the current use of textbooks at UK HE level and the potential for open textbooks. It contextualises and presents the tried and tested methods used to engage with stakeholders at events and workshops and reports back on our findings and outcomes from this activity. Finally this report also presents some of the case studies curated and created during the project; illustrating current best practice and use of open textbooks. The UK Open Textbooks project successfully raised awareness of open textbooks and OER over a one year period, and through the project’s activity discovered that higher and further education is a potentially fertile ground for the use of open textbooks and further development in this area