First report of Desmiphora hirticollis (Olivier) (Coleoptera: Cerambycidae) on Wigandia urens (Ruiz and Pavón) H.B.K. (Hydrophilaceae) in Mexico

Desmiphora hirticollis (Olivier) (Coleoptera: Cerambycidae) was found in Oaxaca, Mexico, feeding in the stems of Wigandia urens (Ruiz and Pavón) H.B.K. (Hydrophilaceae), a new host record. Information about damage in the plant stems and some observations of the insect’s biology are provided

Factores intervinientes en la gestión pedagógica, en estudiantes de la institución educativa Casa Azul

Tesis (Magíster en Gestión Pedagógica y Curricular con Mención en Educación Matemática)La siguiente investigación tiene como finalidad central observar y verificar los factores que influyen en la eficacia de la gestión pedagógica de un establecimiento especifico, Casa Azul que acoge a niños de estrato social bajo. Para llevar a cabo las tareas investigativas, se aplicaron diversos métodos empíricos como instrumentos: entrevista para los directivos, encuesta para el profesorado y observación de la realidad educativa, donde posteriormente, se verificaron sus resultados con un análisis y posibles soluciones para el mejoramiento de todas las debilidades que el establecimiento presentó. Se arribó a resultados obtenidos que demostraron que dentro de la institución educativa se presentan normas pero falta el accionar y dirigir correctamente al equipo de trabajo, para que puedan desarrollar una gestión pedagógica efectiva que optimice el funcionamiento de la comunidad educativa estudiada. La investigación se caracteriza por ser un estudio de metodología cualitativa y cuantitativa, es decir mixta, utilizando dentro de ella métodos teóricos como: histórico lógico, análisis documental y sistematización de información, para organizar la información requerida. El siguiente estudio consta de 4 capítulos entre los cuales se mencionan: marco teórico, marco metodológico, análisis de los resultados y conclusiones

Characterizing organic carbon dynamics during biostimulation of a uranium contaminated field site

Uranium contamination of groundwater remains a pressing problem at many former uranium mining and milling operations, such as the Rifle, Integrated Field Research Challenge (IFRC) site. Biostimulation of the subsurface with an organic carbon source such as acetate, followed by the microbially-induced reductive precipitation of uranium has been proposed as an effective remediation strategy. While uranium bioreduction has been studied in several field experiments, the transformation and fate of injected carbon remains poorly understood. This study evaluated the impact of added organic carbon on the long-term biogeochemical attenuation of uranium in the subsurface of a former mill tailings site. Fluorescence and ultraviolet–visible absorbance analyses were used together with dissolved organic carbon (DOC) measurements to track organic carbon dynamics during and post-biostimulation of the 2011 Rifle IFRC experiment. An electron mass balance was performed on well CD01 to account for any unidentified carbon sinks. Measured DOC values increased to 1.76 mM-C during biostimulation, and to 3.18 mM-C post-biostimulation over background DOC values of 0.3–0.4 mM-C. Elevated DOC levels persisted for 90 days after acetate injections ceased. The electron mass balance revealed that assumed electron acceptors would not account for the total amount of acetate consumed. Excitation–emission matrices showed an increase in signals associated with soluble microbial products, during biostimulation, which disappeared post-biostimulation despite an increase in total DOC. Specific ultraviolet absorbance analyses, indicated that DOC present post-biostimulation is less aromatic in nature, compared to background DOC. Our results suggest that microbes convert injected acetate into a form of solid phase organic matter that may be available to sustain iron reduction post-stimulation

The Frobenius problem: a geometric approach

For the well known Frobenius problem, we present a new geometric approach, based on the use of the $n$-dimensional lattice $\mathbb{Z}^n$, where $n$ is the number of generators. Within this approach we are able to study the cases of two and three generators. The main feature of our geometric representation is that we can nicely visualize the set of {\em gaps}, i.e., the non-representable positive integers. In the case of two generators, we give a description of the set of gaps. Moreover, for any positive integer, $m$, we derive a simple expression for the denumerant $d(m;a,b)$. We show that we can use the $2$-dimensional lattice associated to the set of generators $\{ a,b\}$ to study the Frobenius problem with generators $\{ a,b,c\}$. In particular, we give, as for two generators, a graphical representation of the set of gaps. For a large set of possible values of $c$, this representation allows us to simplify the computation of the Frobenius number and compute the number of gaps

Study of Non-predictive Patterns of Non-Ionizing Radiation in the City of Salta in Argentine

Non-ionizing radiation (NIR) is a subject of continuous debate despite having been regulated internationally and at the level of organizations in all countries. This debate is focused on the level of population exposure to non-ionizing radiation density, since there is no certain evidence of the level of safety of the values adopted ranging from 0.2 mW/cm2 to 0.2 uW/cm2 according to the regulations of each state. The radiation precisions are made with models that evolve to take into account most of the factors that can attenuate the radiation emitted from an antenna from free space to models that take reflection and diffraction as attenuation factors. However, our work deepens in a phenomenon that is verified in measurement campaigns that is one of the values that do not fit with predictive models and that, on the contrary instead of showing attenuation, have higher values than expected. This work shows the results of observation campaigns of these points and their relationship with environmental conditions, which present diverse probabilities to explain their condition

Portico

A partir del inicio del siglo XIX, los viajes de los estadunidenses, por una parte, y de mexicanos, por otra, por el septentrión mexicano se multiplicaron. Con propósitos distintos, los actores de estos periplos escribieron informes, diarios, crónicas de viajes, etc. que nos permiten conocer cómo percibían este inmenso espacio que en gran medida era una terra incognita El propósito de este artículo consiste en dar cuenta del bagaje cultural que unos y otros portaban desde sus respectivos lugares de origen para después comparar los documentos que unos y otros redactaron acerca del mismo territorio pero con "miradas" diferentes

Courant-like brackets and loop spaces

We study the algebra of local functionals equipped with a Poisson bracket. We discuss the underlying algebraic structures related to a version of the Courant-Dorfman algebra. As a main illustration, we consider the functionals over the cotangent bundle of the superloop space over a smooth manifold. We present a number of examples of the Courant-like brackets arising from this analysis.Comment: 20 pages, the version published in JHE

Effects of cardiorespiratory exercise on cognition in older women exposed to air pollution

The aim was to analyze the effects of cardiorespiratory exercise and air pollution on cognition and cardiovascular markers in four groups of older women: the active/clean air group (AC), the active/polluted air group (AP), the sedentary/clean air group (SC), and the sedentary/polluted air group (SP). Active groups performed a training task based on progressive walking. Prior to and after the experiment, the following parameters were assessed: cognition, by Mini Mental State Examination (MMSE); maximum oxygen uptake (VO2max), estimated by the Six-Minute Walk Test (6mWT); heart rate (HR); and oxygen saturation (SpO2). There were significant differences (p < 0.05) between the AC and the SP in all the MMSE dimensions except “Registration”, and in all the physiological variables (VO2max, SpO2, HR). Aerobic exercise may be a protective factor against the effects that pollution have on cognition and on the mechanisms of oxygen transport