23 research outputs found

    Viola gelida, a new, rare and vulnerable rosulate species from the high Andes of Atacama Region, Chile

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    Se provee la descripción para Viola gelida, conocida sólo de dos sitios cercanos en el desierto seco y frío de gran altura. Se identifican las características que distinguen su estrecha relación con Viola exsul y otros parientes cercanos. Además, se discute el contexto de su descubrimiento en un estudio de impacto ambiental obligatorio

    Perspectivas de los Laboratorios Remotos en la Educación Media y Superior de Santiago del Estero

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    El presente artículo tiene como principal objetivo averiguar las perspectivas de los laboratorios remotos en la educación superior y media técnica, con especialidad en electricidad y electrónica, de la ciudad de Santiago del Estero. Motiva este estudio, la instalación de un Laboratorio Remoto VISIR en la Universidad Nacional de Santiago del Estero. Argentina, puesto a disposición de las instituciones de nivel superior y media técnica de la ciudad de Santiago del Estero y con la posibilidad de brindar un servicio del más alto nivel, ajustado a las limitaciones del laboratorio remoto. La metodología utilizada es el Estudio por Encuesta y el instrumento para recolección de datos, el cuestionario. Los resultados indican una aceptación pedagógica del concepto y uso de Laboratorio Remoto. Este estudio sería un punto de partida para investigaciones posteriores que aborden temáticas cada vez más complejas, tales como, la relación entre el rendimiento académico de los alumnos y el uso de laboratorios remotos y/o el incremento en las vocaciones por el estudio de carreras de ingeniería.N/

    A case–control study of infections caused by Klebsiella pneumoniae producing New Delhi metallo-beta-lactamase-1: Predictors and outcomes

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    IntroductionInfections caused by antimicrobial-resistant bacteria are a significant cause of death worldwide, and carbapenemase-producing bacteria are the principal agents. New Delhi metallo-beta-lactamase-1 producing Klebsiella pneumoniae (KP-NDM-1) is an extensively drug-resistant bacterium that has been previously reported in Mexico. Our aim was to conduct a case–control study to describe the risk factors associated with nosocomial infections caused by K. pneumoniae producing NDM-1 in a tertiary-care hospital in Mexico.MethodsA retrospective case–control study with patients hospitalized from January 2012 to February 2018 at the Hospital Civil de Guadalajara “Fray Antonio Alcalde” was designed. During this period, 139 patients with a culture that was positive for K. pneumoniae NDM-1 (cases) and 486 patients hospitalized in the same department and on the same date as the cases (controls) were included. Data were analyzed using SPSS v. 24, and logistic regression analysis was conducted to calculate the risk factors for KP-NDM-1 infection.ResultsOne hundred and thirty-nine case patients with a KP-NDM-1 isolate and 486 control patients were analyzed. In the case group, acute renal failure was a significant comorbidity, hospitalization days were extended, and significantly more deaths occurred. In a multivariate analysis of risk factors, the independent variables included the previous use of antibiotics (odds ratio, OR = 12.252), the use of a urinary catheter (OR = 5.985), the use of a central venous catheter (OR = 5.518), the use of mechanical ventilation (OR = 3.459), and the length of intensive care unit (ICU) stay (OR = 2.334) as predictors of infection with NDM-1 K. pneumoniae.ConclusionIn this study, the previous use of antibiotics, the use of a urinary catheter, the use of a central venous catheter, the use of mechanical ventilation, and ICU stay were shown to be predictors of infection with NDM-1 K. pneumoniae and were independent risk factors for infection with NDM-1 K. pneumoniae

    Real-time Relaxation and Kinetics in Hot Scalar QED: Landau Damping

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    The real time evolution of field condensates with soft length scales k^{-1}>(eT)^{-1} is solved in hot scalar electrodynamics, with a view towards understanding relaxational phenomena in the QGP and the electroweak plasma. We find that transverse gauge invariant non-equilibrium expectation values of fields relax via {\em power laws} to asymptotic amplitudes that are determined by the quasiparticle poles. The long time relaxational dynamics and relevant time scales are determined by the behaviour of the retarded self-energy not at the small frequencies, but at the Landau damping thresholds. This explains the presence of power laws and not of exponential decay. Furthermore, we derive the influence functional, the Langevin equation and the fluctuation-dissipation theorem for the soft modes, identifying the correlation functions that emerge in the classical limit. We show that a Markovian approximation fails to describe the dynamics {\em both} at short and long times. We also introduce a novel kinetic approach that goes beyond the standard Boltzmann equation and incorporates off-shell processes and find that the distribution function for soft quasiparticles relaxes with a power law through Landau damping. We also find an unusual dressing dynamics of bare particles and anomalous (logarithmic) relaxation of hard quasiparticles.Comment: 41 pages, 5 figures, uses revtex, replaced with version to appear in Phys. Rev.

    Chapter 1

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    Experimenting is fundamental to the training process of all scientists and engineers. While experiments have been traditionally done inside laboratories, the emergence of Information and Communication Technologies added two alter-natives accessible anytime, anywhere. These two alternatives are known as virtual and remote labs, and are sometimes indistinguishably referred as online labs. Sim-ilarly to other instructional technologies, virtual and remote labs require some ef-fort from teachers in integrating them into curricula, taking into consideration sev-eral factors that affect their adoption (i.e. cost) and their educational effectiveness (i.e. benefit). This chapter analyses these two dimensions and sustains the case where only through international cooperation it is possible to serve the large num-ber of teachers and students involved in engineering education. It presents an ex-ample in the area of Electrical and Electronics Engineering, based on a remote lab named Virtual Instruments System in Reality, and it then describes how a number of European and Latin-American institutions have been cooperating under the scope of an Erasmus+ project2, for spreading its use in Brazil and Argentina.info:eu-repo/semantics/publishedVersio

    Erratum: Global, regional, and national comparative risk assessment of 84 behavioural, environmental and occupational, and metabolic risks or clusters of risks for 195 countries and territories, 1990–2017: a systematic analysis for the Global Burden of Disease Study 2017

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    Interpretation: By quantifying levels and trends in exposures to risk factors and the resulting disease burden, this assessment offers insight into where past policy and programme efforts might have been successful and highlights current priorities for public health action. Decreases in behavioural, environmental, and occupational risks have largely offset the effects of population growth and ageing, in relation to trends in absolute burden. Conversely, the combination of increasing metabolic risks and population ageing will probably continue to drive the increasing trends in non-communicable diseases at the global level, which presents both a public health challenge and opportunity. We see considerable spatiotemporal heterogeneity in levels of risk exposure and risk-attributable burden. Although levels of development underlie some of this heterogeneity, O/E ratios show risks for which countries are overperforming or underperforming relative to their level of development. As such, these ratios provide a benchmarking tool to help to focus local decision making. Our findings reinforce the importance of both risk exposure monitoring and epidemiological research to assess causal connections between risks and health outcomes, and they highlight the usefulness of the GBD study in synthesising data to draw comprehensive and robust conclusions that help to inform good policy and strategic health planning

    Mar Menor: una laguna singular y sensible. Evaluación científica de su estado.

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    Este libro recopila las aportaciones que equipos de investigación de la Universidad de Murcia, Universidad Politécnica de Cartagena, Instituto Geológico-Minero de España, Universidad de Alicante, el Instituto Español de Oceanografía y otros organismos hicieron en las Jornadas Científicas del Mar Menor, celebradas en diciembre de 2014.La información recogida en este libro se estructura en dos grandes bloques, uno de Biología y Ecología del Mar Menor (capítulos 1 al 8) y otro de Condiciones fisicoquímicas e impacto de actividades humanas en la laguna (capítulos 9 al 14). El primer bloque resume buena parte de los estudios ecológicos realizados en el Mar Menor, que han servido para mejorar su conocimiento y también para cambiar antiguas asunciones sobre la naturaleza y el funcionamiento de estos ecosistemas lagunares (Capítulo 1). El segundo capítulo muestra que esta laguna alberga en zonas someras de su perímetro hábitats fundamentales para mantener y conservar tanto especies migratorias como residentes, que es necesario conocer para paliar el impacto de las actividades humanas que les afectan. En este sentido la reducción de la carga de nutrientes y contaminantes orgánicos e inorgánicos que fluyen hacia el Mar Menor puede ayudar a preservar la laguna en mejores condiciones, bien sea tratando las escorrentías (plantas de tratamiento, humedales artificiales u otras técnicas) y recuperar este agua para uso agrícola o evitar su descarga en la laguna (Capítulo 3). Estas actuaciones serán clave para la conservación de especies emblemáticas como el caballito de mar (Capítulo 4) y reducir el impacto de las proliferaciones masivas de medusas que se producen en la laguna desde 1993 (Capítulo 5). En este mismo sentido los cambios acaecidos en la laguna han favorecido la incursión de invertebrados marinos alóctonos (Capítulo 6) y han afectado a la respuesta de la dinámica poblacional de las aves acuáticas a distintas escalas (Capítulo 7). Para completar este bloque se ofrece una perspectiva histórica de la importancia que ha tenido la investigación sobre acuicultura realizada en esta laguna, que ha servido de base para su gran desarrollo actual (Capítulo 8). El segundo bloque se inicia con una evaluación del origen y evolución del Mar Menor desde el punto de vista geológico, y evidencia su vulnerabilidad ante el deterioro que puede sufrir la desaparición de la barrera de cierre y/o su colmatación (Capítulo 9). En el Capítulo 10 se describe la relevancia que tiene la interacción de los acuíferos del Campo de Cartagena con la laguna, que se produce no sólo a nivel superficial sino también subterráneo. Esta interacción permite el acceso de nutrientes a la laguna, a pesar de la cierta capacidad de depuración de los humedales que le circundan, y también de metales traza por los aportes de residuos mineros (Capítulo 11). De hecho los metales traza están presentes en los sedimentos de la laguna, y su distribución se ha caracterizado en la columna sedimentaria relacionándola con la granulometría y el contenido de materia orgánica del sedimento (Capítulo 12). Posteriormente se describe la entrada de diversos contaminantes orgánicos, incluyendo pesticidas y fármacos a través de la rambla del Albujón, y su distribución estacional en agua y sedimento de la laguna (Capítulo 13). Este segundo bloque finaliza con el Capítulo 14 en el que se describe la bioacumulación de hidrocarburos aromáticos policíclicos, pesticidas y fármacos en moluscos y peces del Mar Menor, así como los efectos biológicos que la carga contaminante que accede a través de la rambla del Albujón produce en los organismos que allí habitan. El libro concluye con un breve epílogo redactado por los editores de este libro.Versión del edito

    Granuloma por Acanthocheilonema spp. em um cão: relato de caso

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    Foi atendido, em uma clínica particular, na cidade de Guaiaquil, Equador, um paciente canino, sem raça definida, de 13 anos de idade, macho, não castrado, de 24kg. O motivo da consulta foi a avaliação de uma massa em região de articulação de joelho direito e de pescoço, que havia sido previamente diagnosticada como de origem neoplásica por outra equipe de médicos veterinários, mediante punção por agulha fina e citologia. Os contactantes eram assintomáticos. No momento da consulta, realizaramse detalhadas avaliações clínica e complementar, que incluíram exames hematológicos, urinálise, citologia da massa, teste sorológico, radiografia torácica e biopsia para posterior estudo histopatológico. O diagnóstico final foi granuloma cutâneo por microfilária de Acanthocheilonema spp., para o qual os tratamentos clínico e cirúrgico apresentaram excelentes resultados. A dirofilariose é uma enfermidade cosmopolita causada por nematódeos do gênero Dirofilaria, sendo a espécie D. immitis a mais conhecida. Em menor frequência, a espécie Acanthocheilonema spp. encontrada neste paciente é também relatada na América, existindo pouco conhecimento a seu respeito. Este é o primeiro relato de caso sobre este tema e espera-se que sirva como base para futuros estudosA canine patient, 13-year-old mixed breed male, 24kg, was seen at a private clinic in the city of Guayaquil, Ecuador. The main reason for consultation was the evaluation of a mass in the right knee and neck that had previously been cytologically diagnosed of neoplastic origin by another team of veterinarians through fine needle puncture and cytology. The contacts were asymptomatic. At the time of the consultation, a detailed exploration and complementary methods were performed that included hematological and urinary exams, mass cytology, serological test, chest radiography and biopsy for further histopathological study. The final diagnosis was a cutaneous granuloma due to microfilariae of Acanthocheilonema spp. and its subsequent surgical and medical treatment with excellent results. The canine heartworm is a cosmopolitan disease caused by nematodes of the genus Dirofilaria, with D. immitis being the best-known species. Less frequently, the species Acanthocheilonema spp., found in this patient, is also reported in Americas, with little knowledge about it. This is the first report of its kind hoping that it will serve as a basis for future studie

    Cutaneous amyloidosis associated with autoimmune hepatitis-primary biliary cirrhosis overlap syndrome

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    Cutaneous amyloidosis is a rare disease characterized by the deposition of amyloid in the dermis. It can be primary or secondary, depending on associated diseases. It has been linked to various autoimmune diseases, including primary biliary cirrhosis. We present the case of a patient with an autoimmune hepatitis-primary biliary cirrhosis overlap syndrome with concomitant cutaneous amyloidosis, a very unusual association, and discuss similar cases and possible pathophysiological implications
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