Combining Magma Flow and Deformation Modeling to Explain Observed Changes in Tilt

The understanding of magma ascent dynamics is essential in forecasting the scale, style and timing of volcanic eruptions. The monitoring of near-field deformation is widely used to gain insight into these dynamics, and has been linked to stress changes in the upper conduit. The ascent of magma through the conduit exerts shear stress on the conduit wall, pulling up the surrounding edifice, whilst overpressure in the upper conduit pushes the surrounding edifice outwards. How much shear stress and pressure is produced during magma ascent, and the relative contribution of each to the deformation, has until now only been explored conceptually. By combining flow and deformation modeling using COMSOL Multiphysics, we for the first time present a quantitative model that links magma ascent to deformation. We quantify how both shear stress and pressure vary spatially within a cylindrical conduit, and show that shear stress generally dominates observed changes in tilt close to the conduit. However, the relative contribution of pressure is not insignificant, and both pressure and shear stress must be considered when interpreting deformation data. We demonstrate that significant changes in tilt can be driven by changes in the driving pressure gradient or volatile content of the magma. The relative contribution of shear stress and pressure to the tilt varies considerably depending on these parameters. Our work provides insight into the range of elastic moduli that should be considered when modeling edifice-scale rock masses, and we show that even where the edifice is modeled as weak, shear stress generally dominates the near field deformation over pressurization of the conduit. While our model addresses cyclic tilt changes observed during activity at Tungurahua volcano, Ecuador, between 2013 and 2014, it is also applicable to silicic volcanoes in general

Viral metagenomic analysis of feces of wild small carnivores

Background: Recent studies have clearly demonstrated the enormous virus diversity that exists among wild animals. This exemplifies the required expansion of our knowledge of the virus diversity present in wildlife, as well as the potential transmission of these viruses to domestic animals or humans. Methods: In the present study we evaluated the viral diversity of fecal samples (n = 42) collected from 10 different species of wild small carnivores inhabiting the northern part of Spain using random PCR in combination with next-generation sequencing. Samples were collected from American mink (Neovison vison), European mink (Mustela lutreola), European polecat (Mustela putorius), European pine marten (Martes martes), stone marten (Martes foina), Eurasian otter (Lutra lutra) and Eurasian badger (Meles meles) of the family of Mustelidae; common genet (Genetta genetta) of the family of Viverridae; red fox (Vulpes vulpes) of the family of Canidae and European wild cat (Felis silvestris) of the family of Felidae. Results: A number of sequences of possible novel viruses or virus variants were detected, including a theilovirus, phleboviruses, an amdovirus, a kobuvirus and picobirnaviruses. Conclusions: Using random PCR in combination with next generation sequencing, sequences of various novel viruses or virus variants were detected in fecal samples collected from Spanish carnivores. Detected novel viruses highlight the viral diversity that is present in fecal material of wild carnivores.The authors would like to thank Peter van Run for excellent technical assistance. In addition, the authors wish to thank all the following researchers and institutions for their invaluable help during sampling and for providing the specimens used in this study, specially to Patricia Lizarraga, Ricardo Gutierrez, and Laura Elorza (Martioda Wildlife Rescue Centre-Alava Regional Council), Luis Javier Chueca (UPV-EHU), Asun Gomez (TRAGSATEC), Maddis Podra (European mink Association) and the technical staff and rangers from La Rioja Government and Alava regional council. We would like to thank also La Rioja Government (Agriculture, Livestock and Environmental Council. General Direction of Natural Environment. Nature Conservation and Planning Service) and Alava Regional Council (Department of Environment. Biodiversity Section) for providing the legal permissions required to develop this study. The research leading to these results has received funding from the European Community's Seventh Framework Programme (FP7/2007 -2013) under the project "European Management Platform for Emerging and Re-emerging Infectious disease Entities" (EMPERIE) EC grant agreement number 223498, the VIRGO Consortium and the Niedersachsen-Research Network on Neuroinfectiology (N-RENNT) of the Ministry of Science and Culture of Lower Saxony. In addition, this research has been partially funded by the Basque Government through the Research group on "Systematics, Biogeography and Population Dynamics" (Ref. IT317-10; GIC10/76). A. Ruiz-Gonzalez holds a Post doc fellowship awarded by the Department of Education, Universities and Research of the Basque Government (Ref. DKR-2012-64) and was awarded by a short visit Research grant from the ConGenOmics Research networking programme of the European Science Foundation (ESF) in order to visit the Department of Viroscience, Erasmus Medical Centre and develop the current research project

Mexico City and the biogeochemistry of global urbanization

Mexico City is far advanced in its urban evolution, and cities in currently developing nations may soon follow a similar course. This paper investigates the strengths and weaknesses of infrastructures for the emerging megacities. The major driving force for infrastructure change in Mexico City is concern over air quality. Air chemistry data from recent field campaigns have been used to calculate fluxes in the atmosphere of the Valley of Mexico, for compounds that are important to biogeochemistry including methane (CH4), carbon monoxide (CO), nonmethane hydrocarbons (NMHCs), ammonia (NH3), sulfur dioxide (SO2), nitrogen oxides (NOx and NOy), soot, and dust. Leakage of liquified petroleum gas approached 10% during sampling periods, and automotive pollutant sources in Mexico City were found to match those in developed cities, despite a lower vehicle-to-person ratio of 0.1. Ammonia is released primarily from residential areas, at levels sufficient to titrate pollutant acids into particles across the entire basin. Enhancements of reduced nitrogen and hydrocarbons in the vapor phase skew the distribution of NOy species towards lower average deposition velocities. Partly as a result, downwind nutrient deposition occurs on a similar scale as nitrogen fixation across Central America, and augments marine nitrate upwelling. Dust suspension from unpaved roads and from the bed of Lake Texcoco was found to be comparable to that occurring on the periphery of the Sahara, Arabian, and Gobi deserts. In addition, sodium chloride (NaCl) in the dust may support heterogeneous chlorine oxide (ClOx) chemistry. The insights from our Mexico City analysis have been tentatively applied to the upcoming urbanization of Asia

Microencapsulation techniques: a proposal for microencapsulated probiotics.

A la hora de utilizar probióticos, el principal problema que se presenta, es la escasa resistencia de estos a diferentes condiciones ambientales y tecnológicas. Las técnicas de microencapsulación son un buen método para proteger a estos microorganismos, sin embargo no todas las técnicas son apropiadas para los probióticos. En este artículo proponemos la técnica de gelificación interna, que por sus características permite la obtención de un tamaño de partícula adecuado y la supervivencia de los microorganismos.The main problem when probiotics are used is the low resistance of these to different environmental and technological conditions. The microencapsulation techniques are a good method in order to protect the probiotics, Nevertheless not all techniques of microencapsulation are suitable for probiotics. In this paper, we propose the internal gelification which allows us to obtain a suitable particle size and the survival of the microorganisms

Age-related variation in the trophic characteristics of a marsupial carnivore, the Tasmanian devil Sarcophilus harrisii

This is the final version. Available on open access from Wiley via the DOI in this recordAge-related changes in diet have implications for competitive interactions and for predator–prey dynamics, affecting individuals and groups at different life stages. To quantify patterns of variation and ontogenetic change in the diets of Tasmanian devils Sarcophilus harrisii, a threatened marsupial carnivore, we analyzed variation in the stable isotope composition of whisker tissue samples taken from 91 individual devils from Wilmot, Tasmania from December 2014 to February 2017. Both δ13C and δ15N decreased with increasing age in weaned Tasmanian devils, indicating that as they age devils rely less on small mammals and birds, and more on large herbivores. Devils <12 months old had broader group isotopic niches, as estimated by Bayesian standard ellipses (SEAB mode = 1.042) than devils from 12 to 23 months old (mode = 0.541) and devils ≥24 months old (mode = 0.532). Devils <24 months old had broader individual isotopic niches (SEAB mode range 0.492–1.083) than devils ≥24 months old (mode range 0.092–0.240). A decrease in δ15N from the older whisker sections to the more recently grown sections in devils <24 months old likely reflects the period of weaning in this species, as this pattern was not observed in devils ≥24 months old. Our data reveal changes in the isotopic composition of devil whiskers with increasing age, accompanied by a reduction in isotopic variation both among population age classes and within individuals, reflecting the effect of weaning in early life, and a likely shift from an initially diverse diet of small mammals, birds, and invertebrates towards increasing consumption of larger herbivores in adulthood.Natural Environment Research Council (NERC)University of Exete