141 research outputs found

    La "seca" de olivos jóvenes II: identificación y patogenicidad de los hongos asociados con podredumbres radicales

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    This work deals with the identification of fungal isolates associated with root rot, the major factor included in the «drying and death syndrome» («seca») of young olive trees in Andalucía, southern Spain. Fungi associated with damping-off in olive tree nurseries were also identified. Several isolates from every fungal species were tested for pathogenicity in nursery plants and rooted cuttings of olive cultivar 'Picual'. Pathogenicity tests demonstrated that five fungal species -Cylindrocarpon destructans, Phytophthora megasperma, P. palmivora, Pythium irregulare and Sclerotium rolfsii- were clearly pathogenic to olive trees and reproduced symptoms of root rot and foliar wilting. Other fungal species associated with root rot of olive trees in the field or in the nurseries, including Fusarium acuminatum, F. eumartii, F. oxysporum, F. solani, Macrophomina phaseolina and Rhizoctonia solani, were weakly or not pathogenic. Pathogenicity of Phytophthora megasperma, P. palmivora and Pythium irregulare depended on soil water content, since isolates tested only caused extensive root rot and sudden plant death when the soil was continuously waterlogged. The high frequency of P. megasperma (part I) and its dependence for pathogenicity on soil water content suggest that this pathogen may play an important role in the well known sensitivity of young olive trees to «root asphyxiation».En este trabajo se han identificado los aislados fúngicos asociados a las podredumbres radiculares de olivo, el factor más importante incluido bajo la denominación genérica de «seca» de olivos jóvenes en Andalucía, así como los aislados asociados a la muerte de plántulas («damping-off») en viveros de olivo. La patogenicidad de aislados seleccionados de cada especie fúngica se evaluó en plantones y estaquillas enraizadas de olivo del cultivar «Picual», en condiciones parcialmente controladas. De todas las especies ensayadas, cinco mostraron claramente su patogenicidad en olivo: Cylindrocarpon destructans, Phytophthora megasperma, P. palmivora, Pythium irregulare y Sclerotium rolfsii, reproduciendo los síntomas de podredumbre radicular y marchitez foliar en las plantas inoculadas. Otras especies asociadas a podredumbres radiculares en campo y vivero {Fusarium acuminatum, F. eumartii, F. oxysporum, F. solani, Macrophomina phaseolina y Rhizoctonia solani) resultaron débilmente o nada patogénicas. La patogenicidad de Phytophthora megasperma, P. palmivora y Pythium irregulare resultó dependiente del contenido hídrico del suelo, ya que los aislados ensayados sólo causaron necrosis extensas del sistema radicular y muerte de las plantas inoculadas en condiciones de saturación continua del suelo. La elevada frecuencia de aislamiento de Phytophthora megasperma en suelos encharcados (parte I) y su dependencia patogénica del exceso de agua en el suelo sugieren que este hongo puede jugar un papel importante en la generalmente aceptada sensibilidad de los olivos jóvenes a la «asfixia radicular»

    Evaluation of interindividual and intraindividual variability in basketball jump throws through biomechanical analysis

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    El objetivo del presente estudio ha sido cuantificar las diferencias en la ejecución del lanzamiento en salto analizando la variabilidad intrasujetos e intersujetos. En la mayoría de las investigaciones, donde se pretende estudiar un gesto deportivo desde el punto de vista biomecánico, se selecciona el mejor intento, determinado por el rendimiento obtenido en términos de distancia o altura alcanzada del lanzamiento, descartándose la posibilidad de intravariabilidad entre ensayos. Sin embargo, este aspecto de variabilidad, no debe ser del todo olvidado en gestos como el lanzamiento en salto baloncesto, donde las condiciones contextuales de su aplicación se modifican constantemente durante la competición y donde la variabilidad intrasujeto podría aportarnos mayor conocimiento de este gesto. La muestra ha estado compuesta por jugadores profesionales de baloncesto pertenecientes a la liga ACB, utilizando la fotogrametría tridimensional para el análisis del gesto. Los resultados obtenidos, indican que la intervariabilidad es mayor que la intravariabilidad en todas las variables cinemáticas analizadas.Peer Reviewe

    Challenges in the COVID-19 vaccination era: Prioritization of vaccines among essential workers in Mexico

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    The coronavirus disease-2019 (COVID-19) pandemic gave rise to a massive global health concern that has placed an unprecedented strain on healthcare systems, education and economy. The recent vaccine roll-out gave humanity a glimpse of hope. However, more than 50% of the vaccine supply has been acquired by high-income countries, forcing low- and middle-income countries to prioritize who should be vaccinated. In Mexico, the first phase of the vaccination program prioritized healthcare personnel working in front-line COVID-19 public institutions. The second phase was planned for the remaining healthcare workers attending at both COVID and non-COVID areas. The government, however, aiming to reopen schools, decided to vaccinate teachers instead. This raised several concerns, since Mexico tops the ranking of deaths among healthcare workers due to COVID-19 worldwide. Furthermore, the possible framing of vaccines as a political tool has caused commotion among the Mexican people and media, especially since 2021 is the Midterm Election year in Mexico, and the Teachers’ Union has historically played an essential role in this matter. Therefore, it is relevant to share the vaccination experience in resource-constrained settings to provide help and advice to reach an optimal strategy and deflate this pandemic

    Public Policies for the Development of Agroecosystems Resilient to Climate Change

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    Objective: Analyze public policies in Mexico facing climate change in agriculture that allow the development of resilient agroecosystems. Design/methodology/approach: An analysis of research on resilience to climate change in the agricultural and rural sectors, as well as analysis of literature on public policies formulated to climate change in the agricultural sector (period 2013-2019), was realized. Results: Multiple sources of resilience for agroecosystems are present. Policies could be oriented to identify such sources and to strengthen capacities according to different scales and contexts. There is the possibility of considering factors associated with the evolution of these systems to employ strategies that are consistent and that allow coordination between political levels. Limitations of the study/Implications: This is a theoretical study restricted to the available literature published until 2019. Findings/Conclusions: Public policies require integrating the perspective of the dynamics of the complex agricultural system and the multiple sources of resilience at different scales and contexts, articulating the development of resilient agroecosystems to climate change.Objective: Analyze public policies in Mexico facing climate change in agriculture that allow the development of resilient agroecosystems. Design/methodology/approach: An analysis of research on resilience to climate change in the agricultural and rural sectors, as well as analysis of literature on public policies formulated to climate change in the agricultural sector (period 2013-2019), was realized. Results: Multiple sources of resilience for agroecosystems are present. Policies could be oriented to identify such sources and to strengthen capacities according to different scales and contexts. There is the possibility of considering factors associated with the evolution of these systems to employ strategies that are consistent and that allow coordination between political levels. Limitations of the study/Implications: This is a theoretical study restricted to the available literature published until 2019. Findings/Conclusions: Public policies require integrating the perspective of the dynamics of the complex agricultural system and the multiple sources of resilience at different scales and contexts, articulating the development of resilient agroecosystems to climate change

    Las emociones en la enseñanza de las ciencias

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    En la primera parte del artículo, se incide en la importancia del estudio de las emociones desde la didáctica de las ciencias, así como en la necesidad de establecer programas de intervención metacognitivos y metaemocionales, tanto en el aprendizaje como en la formación del profesorado, para que alumnos y profesores puedan conocer sus emociones, controlarlas y autorregularlas. En la segunda parte, nos centramos en las emociones en el conocimiento didáctico del contenido del profesorado de ciencias, incluyendo algunos resultados tanto del diagnóstico emocional del profesorado, según distintas variables, como del programa de intervención de la Universidad de Extremadura.The first part of this communication highlights the importance of studying emotions in the context of science teaching. It also examines the need for programs of meta-emotional and metacognitive intervention in learning and teacher education that are aimed at both the future teachers'and their pupils' gaining awareness of, and then controlling and self-regulating, their emotions. The second part focuses on the role emotions play in science teachers' pædagogical content knowledge, with the presentation of some results concerning the University of Extremadura's intervention program and the emotional diagnosis of teachers.En la primera part de l'article, s'incideix en la importància de l'estudi de les emocions des de la didàctica de les ciències, així com en la necessitat d'establir programes d'intervenció metacognitivos i metaemocionales, tant en l'aprenentatge com en la formació del professorat, perquè alumnes i professors puguin conèixer les seves emocions, controlar-les i autorregularlas. En la segona part, ens centrem en les emocions en el coneixement didàctic del contingut del professorat de ciències, incloent alguns resultats tant del diagnòstic emocional del professorat, segons diferents variables, com del programa d'intervenció de la Universitat d'Extremadura

    Clinical efficacy of β-lactam/β-lactamase inhibitor combinations for the treatment of bloodstream infection due to extended-spectrum β-lactamase-producing Enterobacteriaceae in haematological patients with neutropaenia: a study protocol for a retrospective observational study (BICAR)

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    Introduction: Bloodstream infection (BSI) due to extended-spectrum β-lactamase-producing Gram-negative bacilli (ESBL-GNB) is increasing at an alarming pace worldwide. Although β-lactam/β-lactamase inhibitor (BLBLI) combinations have been suggested as an alternative to carbapenems for the treatment of BSI due to these resistant organisms in the general population, their usefulness for the treatment of BSI due to ESBL-GNB in haematological patients with neutropaenia is yet to be elucidated. The aim of the BICAR study is to compare the efficacy of BLBLI combinations with that of carbapenems for the treatment of BSI due to an ESBL-GNB in this population. Methods and analysis: A multinational, multicentre, observational retrospective study. Episodes of BSI due to ESBL-GNB occurring in haematological patients and haematopoietic stem cell transplant recipients with neutropaenia from 1 January 2006 to 31 March 2015 will be analysed. The primary end point will be case-fatality rate within 30 days of onset of BSI. The secondary end points will be 7-day and 14-day case-fatality rates, microbiological failure, colonisation/infection by resistant bacteria, superinfection, intensive care unit admission and development of adverse events. Sample size: The number of expected episodes of BSI due to ESBL-GNB in the participant centres will be 260 with a ratio of control to experimental participants of 2. Ethics and dissemination: The protocol of the study was approved at the first site by the Research Ethics Committee (REC) of Hospital Universitari de Bellvitge. Approval will be also sought from all relevant RECs. Any formal presentation or publication of data from this study will be considered as a joint publication by the participating investigators and will follow the recommendations of the International Committee of Medical Journal Editors (ICMJE). The study has been endorsed by the European Study Group for Bloodstream Infection and Sepsis (ESGBIS) and the European Study Group for Infections in Compromised Hosts (ESGICH)

    Continuous GPS stations deployment in the Topo-Iberia Project framework

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    Topo-Iberia es un proyecto financiado por el Ministerio de Educación y Ciencia de España. Su principal objetivo es comprender las interacciones entre los procesos profundos, superficiales y atmosféricos integrando datos geológicos, geofísicos y geodéticos. El proyecto se centrará en tres zonas principales de interés en la Península Ibérica: los bordes N y S de la Placa Ibérica (incluyendo el N de Marruecos) y su núcleo central intermedio. Presentamos las actividades preliminares realizadas por el subgrupo GPS de Topo-Iberia con el fin de desplegar una nueva red continua de GPS. La intención es complementar las redes CGPS continuas existentes (p.e. ROA; ERGPS) incrementado la cobertura espacial en España y N de Marruecos. Una vez seleccionados los emplazamientos de las nuevas estaciones, el objetivo es que se encuentren en pleno funcionamiento la primavera de 2008. Se han descargado conjuntos de datos CGPS de servidores de distintas instituciones sobre los que se ha realizado un procesado inicial que sirva como control de calidad. Como algunas de las estaciones actualmente disponibles no siguen los estrictos procedimientos de estabilidad dictados por IGS/EUREF, estamos evaluando sus resultados mediante análisis de series temporales para decidir cuales se pueden incluir como estaciones complementarias de la red Topo-Iberia.Topo-Iberia is a Spanish Research Council funded project. Its main objective is to understand the interactions between deep, shallow and atmospheric processes, integrating geological, geophysical, geodetic and geo-technological research activities. The project will focus in three main areas of interest in the Iberian Peninsula: Northern and Southern borders of the Iberian micro-plate (taking into account the Northern part of Morocco), and its central core. We present the preliminary steps that the Topo- Iberia GPS working group is undergoing in order to deploy a new Continuous GPS Network. We are trying to complement the existing and functioning CGPS Networks (e.g. ROA; ERGPS) by increasing the spatial coverage across Spain and Northern Morocco. The places for the new locations have been chosen and all stations should be working in the spring 2008. A set of available CGPS data files has been downloaded from different institutional servers. A preliminary data analysis has been performed for geodetic quality control. Since some of the existing CGPS stations have been installed without following strict IGS/EUREF procedures for the stability of the monuments, we are evaluating their performance through the time series analysis, in order to decide whether to include them as complementing stations to our network.Depto. de Geodinámica, Estratigrafía y PaleontologíaFac. de Ciencias GeológicasTRUEMinisterio de Ciencia e Innovación (MICINN)CONSOLIDER TOPO-Iberiapu
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