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

Evaluation of Bacterial Resistance to Antibiotics in Stool Samples Obtained from Guinea Pigs (Cavia porcellus) in Family and Family-commercial Farms

The inappropriate use of antimicrobial agents in guinea pigs to control enteric pathogens affects the nutritional sustainability of the rural population. Therefore, it is important to identify the pathogen, its resistance, and the appropriate antimicrobial agent for its control. The present investigation was carried out in family and family-commercial guinea pig farms, in eight rural parishes of the Gualaceo canton, Azuay province, Ecuador, from which 384 samples were obtained by rectal swabbing of guinea pigs from production units with enteric problems (diarrhea), the same ones that were transferred to the laboratory of the Faculty of Agricultural Sciences of the University of Cuenca, in order to identify the bacterial agents present in fecal samples of guinea pigs. There the isolation of culture media and identification of pathogens were carried out, they were subsequently exposed to an antibiogram, in order to qualitatively assess their bacterial resistance. The data were tabulated and analyzed in SPSS, finding the presence of Escherichia coli (49.4%), Salmonella typhimurium (24.6%), Shigella flexneri (14.3%), and Klebsiella pneumoniae (11.7%). The Chi-square test determined that of the five antimicrobials used, only tetracycline had a relationship between bacterial presence and resistance. It was also found that Escherichia coli presented a higher percentage of resistance, for enrofloxacin 22.5%, neomycin 14.2%, sulfamethoxazole - trimethoprim 33.3%, tetracyclines 29.2%. Data were analyzed at a confidence level of 95% with a 5% error, concluding that the identified pathogens have low resistance to the antimicrobials used, but are still susceptible. Keywords: bacterial resistance, antibiogram, enteric infection, antibiotics. Resumen El uso inadecuado de agentes antimicrobianos en cobayos para controlar patógenos entéricos, afectan la sustentabilidad alimenticia de la población rural, por ello es importante identificar el patógeno, su resistencia y el agente antimicrobiano adecuado para su control. La presente investigación se realizó en explotaciones de cobayos de tipo familiar y familiar – comercial, en ocho parroquias rurales del cantón Gualaceo provincia del Azuay, Ecuador de donde se obtuvo 384 muestras mediante hisopado rectal de cobayos provenientes de unidades productoras con problemas entéricos (diarrea), las mismas que fueron trasladadas al laboratorio de la Facultad de Ciencias Agropecuarias de la Universidad de Cuenca, con el fin de identificar los agentes bacterianos presentes en muestras fecales de cobayos, ahí se realizó la infección de medios de cultivo e identificación de agentes patógenos, mismos que posteriormente fueron expuestos a un antibiograma, con la finalidad de evaluar cualitativamente su resistencia bacteriana. Los datos fueron tabulados y analizados en SPSS, encontrándose la presencia de Escherichia coli (49,4%), Salmonella typhimurium (24,6%), Shigella flexneri (14,3%) y Klebsiella pneumoniae (11,7%). En la prueba de chi 2, se determinó que de los cinco antimicrobianos usados, solamente la Tetraciclina tiene relación entre la presencia bacteriana y la resistencia; también se encontró que Escherichia coli presentó mayor porcentaje de resistencia, para Enrofloxacina 22,5%, Neomicina 14,2%, Sulfametoxazol – trimetoprim 33,3%, Tetraciclinas 29,2%, datos que fueron analizados a un nivel de confianza del 95% con un 5% de error, concluyendo que los patógenos identificados presentan baja resistencia a los antimicrobianos utilizados, pero aún son susceptibles. Palabras Clave: resistencia bacteriana, antibiograma, infección entérica, antibióticos

Quantitative analysis of numerical estimates for the permeability of porous media from lattice-Boltzmann simulations

During the last decade, lattice-Boltzmann (LB) simulations have been improved to become an efficient tool for determining the permeability of porous media samples. However, well known improvements of the original algorithm are often not implemented. These include for example multirelaxation time schemes or improved boundary conditions, as well as different possibilities to impose a pressure gradient. This paper shows that a significant difference of the calculated permeabilities can be found unless one uses a carefully selected setup. We present a detailed discussion of possible simulation setups and quantitative studies of the influence of simulation parameters. We illustrate our results by applying the algorithm to a Fontainebleau sandstone and by comparing our benchmark studies to other numerical permeability measurements in the literature.Comment: 14 pages, 11 figure

Mathematical and physical techniques of modeling and simulation of pattern recognition in the stock market

The following article presents the analysis through mathematical and physical techniques of large databases, which are very common today, due to the large number of variables (especially in the information and physics industry) and the amount of information that results from a process, therefore an analysis is necessary that allows the Decision in a responsible manner, looking for scientific criteria that support said decisions, in our case a database of the forex system will be taken. Initially, a study and calculation of different measurements between the samples and their characteristics will be carried out to make a good prediction of the data and their behavior using different classification methods inspired by basic sciences. Below is an explanation of the techniques based on the analysis of data components and the correlations that exist between the variables, which is a technique widely used in physical processes to determine the correlations between variables

Primeras exhibiciones audiovisuales en la ciudad de Zacatecas: Precine y cinematógrafo (1898-1930)

This article analyzes in a documented way the first years of the cinematic exhibition in Zacatecas. The information offered by the author supposes an update of the existing bibliography providing an array of documentary sources obtained at local archives. The article reports an important chapter in the origins of the cinematic phenomenon, while it provides new information for the historiography of the Mexican cinema.Keywords: history, cinematograph, pre-cinema, Zacatecas.___________Primeras exhibiciones audiovisuales en la ciudad de Zacatecas: Precine y cinematógrafo (1898-1930)El presente artículo analiza de manera documentada los primeros años de la exhibición cinematográfica en Zacatecas. Los datos ofrecidos suponen una actualización de la bibliografía existente ya que se han consultado las fuentes documentales de los archivos locales. El artículo relata una parte importante del hecho cinematográfico de los orígenes, al tiempo que aporta nuevos datos para la historiografía del cine mexicano.Palabras clave: historia, cinematógrafo, precine, Zacatecas.___________Primeiras exibições audiovisuais na cidade de Zacatecas: Pré-cinema e cinematógrafo (1898-1930)Resumo: Resumo: Este artigo analisa a forma documentada nos primeiros anos de exibição cinematográfica na cidade de Zacatecas (México). Os dados apresentados são uma atualização da bibliografia, uma vez que tenha consultado fontes documentais de arquivos locais. O artigo relata uma parte importante do filme feito das origens, ao fornecer novos dados para a historiografia do cinema mexicano.Palavras chave: história, cinematógrafo, Zacatecas. pré-cinema___________Fecha de recepción: 8 de septiembre de 2015Fecha de aceptación: 8 de diciembre de 2015El presente artículo analiza de manera documentada los primeros años de la exhibición cinematográfica en Zacatecas. Los datos ofrecidos suponen una actualización de la bibliografía existente ya que se han consultado las fuentes documentales de los archivos locales. El artículo relata una parte importante del hecho cinematográfico de los orígenes, al tiempo que aporta nuevos datos para la historiografía del cine mexicano.Palabras clave: historia, cinematógrafo, precine, Zacatecas.___________First audiovisual exhibitions in Zacatecas: precinema and cinema (1898-1930).Abstract: This article analyzes in a documented way the first years of the cinematic exhibition in Zacatecas. The information offered by the author supposes an update of the existing bibliography providing an array of documentary sources obtained at local archives. The article reports an important chapter in the origins of the cinematic phenomenon, while it provides new information for the historiography of the Mexican cinema.Keywords: history, cinematograph, pre-cinema, Zacatecas.___________Primeiras exibições audiovisuais na cidade de Zacatecas: Pré-cinema e cinematógrafo (1898-1930)Resumo: Resumo: Este artigo analisa a forma documentada nos primeiros anos de exibição cinematográfica na cidade de Zacatecas (México). Os dados apresentados são uma atualização da bibliografia, uma vez que tenha consultado fontes documentais de arquivos locais. O artigo relata uma parte importante do filme feito das origens, ao fornecer novos dados para a historiografia do cinema mexicano.Palavras chave: história, cinematógrafo, Zacatecas. pré-cinema___________Fecha de recepción: 8 de septiembre de 2015Fecha de aceptación: 8 de diciembre de 201

Arte e ideología en el cine de S. M. Eisenstein

Eisenstein, who was born hundred years ago, is considered one of the greatest filmmakers in History. Committed to Bolshevik ideas and as supporter of the October Revolution, he wanted to use film as another vehicle in the awareness of the masses. Although he faced the most orthodox sectors of Stalinism, Eisenstein knew at all times to put into practice a series of theoretical ideas related to sound and color. The implementation of these, not only served for ideological purposes, but also converted their films into authentic works of art. For this,  he not only researched in arts and color theory, but also chose to introduce in his work references to other cultures (such as the Kabuki), avant-garde artists (Kandinsky) and musicians such as Prokofiev. The present essay analyzes the connections between Eisenstein and all of them, and specially how he performed these revolutionary ideas.Eisenstein, de cuyo nacimiento se cumplen cien años, es considerado uno de los más grandes cineastas de la Historia. Comprometido con las ideas bolcheviques y partidario de la Revolución de Octubre, quiso utilizar el cine como un vehículo más en la concienciación de las masas. Si bien se enfrentó a los sectores más ortodoxos del estalinismo, Eisenstein supo en todo momento llevar a la práctica una serie de ideas teóricas relacionadas con el sonido y el color. La puesta en práctica de éstas, no solo sirvieron para los fines ideológicos, sino que además convirtieron sus películas en auténticas obras de arte. Para ello no solo investigó en artes plásticas y teoría del color, sino que también optó por introducir en su obra referencias a otras culturas (como el Kabuki), artistas de vanguardia (Kandinsky) y músicos como Prokofiev. En el presente artículo se analizan las conexiones de Eisenstein con todos ellos y sobre todo la puesta en escena de estas ideas tan revolucionarias

La evaluación en carreras científicas: del concepto a la concreción

Se describen situaciones contradictorias en relación a la evaluación del aprendizaje en estudiantes universitarios, con especial énfasis en los métodos empleados en carreras del área científica, su coherencia con las metodologías didácticas y su pertinencia en el contexto histórico de la enseñanza universitaria y de las ciencias en particular, con el objetivo de avanzar en aspectos reflexivos y promover el mejoramiento y transformación de las prácticas evaluativas más comunes

Changes in volatile compounds of pork loin (fresh and marinated) with different irradiation and packaging during storage

The analysis of volatile compounds by gas chromatography- mass spectrometry after extraction by purge and trap has been used to investigate the volatile compounds of fresh and marinated pork loin after E-beam treatmet as a function of packaging type (air, vacuum and modified atmosphere), radiation dose (1 and 2 kGy) and storage temperature (4 and 8 °C). Major differences were found between fresh and marinated samples but, in general, only minor differences were found in the volatile compounds of both types of loin due to storage temperature, packaging method and doses of irradiation. It is concluded that the application of E-beam is a very useful way to extend the shelflife of fresh and marinated pork loin with no changes in the odor of the products.<br><br>Se ha utilizado la cromatografía de gases/espectrometría de masas, la extracción mediante purga y trampa para estudiar los compuestos volátiles de lomo de cerdo fresco y adobado, tratados con electrones acelerados (1 y 2 kGy) y almacenado en refrigeración (4 y 8 °C) bajo diferentes atmósferas (aire, vacío y atmósfera modificada). Se observaron diferencias importantes entre las muestras de lomo fresco y adobado pero, en general, solo pequeñas diferencias fueron observadas en algunos compuestos volátiles de ambos tipos de lomo debidas al efecto de la temperatura, tiempo de almacenamiento, tipo de atmósfera o dosis de radiación. Se ha concluido que la aplicación de electrones acelerados es una tecnología muy eficaz para ampliar la vida útil del lomo de cerdo fresco y adobado sin que se detecten cambios en el olor de los productos