Short-term study of effects of fertilisation and cutting treatments on the vegetation dynamics of mountain heathlands in Spain

P. 181-191La influencia de la gestión y la disponibilidad de nutrientes en la dinámica de la vegetación de páramos caracterizados por Calluna vulgaris y Erica tetralix fueron estudiados en tres sitios de la montaña en el norte de España. En un total de 90 parcelas (1 m2 cada uno) recibieron diferentes combinaciones de corte y dos veces el fondo deposición atmosférica estimada de nitrógeno (56 kg yr_1 ha_1). Una de las dos especies dominantes ericáceas fueron cortados selectivamente a mano a nivel del suelo y su regeneración comparan en la presencia o ausencia de la otra. Los resultados después de 2 años mostraron efectos significativos del fertilizante en la cubierta vegetal, principalmente favoreciendo especies herbáceas perennes. No hubo efectos menos notables en el número de flores y sobre el crecimiento anual de las especies de ericáceas. Se concluye que, en el corto plazo, los nutrientes aumentaron solo, al doble de la deposición atmosférica corriente estimado para la zona, no va a alterar significativamente la composición de los brezales de montaña. Sin embargo, una vez que las gradas llegan a la fase de madurez, la capacidad de la comunidad para regenerar después disminuye una perturbación grave. Un impacto drástico, como el corte no puede dar lugar a la re-crecimiento de las mismas especies de arbustos, sino en sustitución por especies herbáceas, que también se beneficiarán de la mayoría de los nutrientesS

Diseño e implementación de un VANT (Vehículo Aéreo No-Tripulado, Unmanned Aerial Vehicule, UAV) multisensor para estudios post-incendio en entornos forestales

Los Vehículo Aéreo No-Tripulados (VANTs, Unmanned Aerial Vehicules, UAVs) son una ayuda en la prevención, detección, y extinción de incendios forestales. Estamos convencidos de su utilidad también en el posterior análisis de daños ocasionados por el fuego, a pesar de que no hemos localizado ningún estudio científico que lo demuestre. Por este motivo, en este trabajo se diseña e implemente un VANT especializado en esta tarea (recoger información para análisis de daños postincendio) y en general, un VANT orientado al obtención de imágenes de alta resolución espacial utilizadas en estudios forestales. El primer paso, fue el análisis de las características que dicho VANT debe tener. A continuación, se diseñó e implementó un VANT con bahía extraíble para portar múltiples sensores. Se buscó que el diseño fuera modular, que se adaptara a las diferentes cargas de pago, para aportar flexibilidad y que pudiera despegar/aterrizar en entornos forestales. Tras el diseño y construcción del VANT se realizaron diferentes pruebas de vuelo, todas con resultados satisfactorios. Por este motivo, concluimos que el VANT construido que cumple todos los criterios para trabajar en entornos forestales (especialmente en entornos post-incendio) es una herramienta de gran valor para monitorizar los efectos del fuego en la cubierta foresta

Relatos digitales de adolescentes y jóvenes en la nueva ecología de la participación

Podeu consultar el llibre complet a: http://hdl.handle.net/2445/164579[spa] El objetivo del estudio presentado ha sido conocer los hábitos y prácticas de consumo y publicación de historias de los jóvenes en las redes y medios sociales digitales. Para ello se ha utilizado un metodología de encuesta mediante un cuestionario en línea el cual se ha aplicado a una muestra por conveniencia y por conglomerados de 835 estudiantes de 12 a 22 años de España, Chile y Colombia. Entre los resultados destacan que el tipo de publicación principal de los jóvenes es la foto y la selfi, que los temas de publicación son pasatiempos, gustos y aficiones creados principalmente por ellos mismos, la hora preferida para publicar es la tarde, o que comparten sus publicaciones con sus contactos. Los resultados pueden ayudar a establecer criterios adaptados a los hábitos de los jóvenes para orientarlos en actividades de creación de relatos digitales de tipo personal a la luz del concepto de las nuevas alfabetizaciones.[eng] The study aims to know the habits and practices of consumption and publication of stories of young people on digital social media and digital social networks. For this, a survey methodology has been used through an online questionnaire which has been applied to a clustered and purposive sample of 835 students from 12 to 22 years old, from Spain, Chile and Colombia. Among the results, the main types of publication are photos and selfies created mostly by themselves, the topics of their publications are mostly hobbies, the preferred time to publish is in the afternoon, and they share their publications mainly with their contacts. The results can help establish criteria adapted to the habits of young people to guide them in the creation of personal digital storytelling activities in light of the concept of new literacies

Efficacy of laser shock processing of biodegradable Mg and Mg-1Zn alloy on their in vitro corrosion and bacterial response

Laser shock processing (LSP) is increasingly applied as an effective technology for improving the properties of different metallic components. This is done principally to enhance their corrosion and fatigue life behaviour, stress corrosion cracking resistance, etc. In this paper, LSP has been applied to a commercially pure Mg and a Mg-1Zn alloy (wt%) which is aimed to be used as a biodegradable material for biomedical applications. The rational for microalloying with Zn is not only influencing the bacterial response, but also enhancing corrosion resistance and mechanical strength of Mg without causing any toxic effect. The present work is focussed on the examination of the effects of the LSP treatment on the relevant surface related properties of the samples and their correlation with the surface and subsurface induced modifications such as residual stress state, microstructural, roughness, hardness, etc. Central to this investigation is the study of the corrosion response and antibacterial properties against Staphylococcus epidermidis of the different samples as a function of material and LSP parameters. The results show that the application of LSP introduces compressive residual stresses up to 1 mm deep. This occurs together with a significant improvement in corrosion resistance, and less bacterial colonization.Peer reviewe

The effect of post-discharge educational intervention on patients in achieving objectives in modifiable risk factors six months after discharge following an episode of acute coronary syndrome, (CAM-2 Project): a randomized controlled trial

<p>Abstract</p> <p>Objectives</p> <p>We investigated whether an intervention mainly consisting of a signed agreement between patient and physician on the objectives to be reached, improves reaching these secondary prevention objectives in modifiable cardiovascular risk factors six-months after discharge following an acute coronary syndrome.</p> <p>Background</p> <p>There is room to improve mid-term adherence to clinical guidelines' recommendations in coronary heart disease secondary prevention, specially non-pharmacological ones, often neglected.</p> <p>Methods</p> <p>In CAM-2, patients discharged after an acute coronary syndrome were randomly assigned to the intervention or the usual care group. The primary outcome was reaching therapeutic objectives in various secondary prevention variables: smoking, obesity, blood lipids, blood pressure control, exercise and taking of medication.</p> <p>Results</p> <p>1757 patients were recruited in 64 hospitals and 1510 (762 in the intervention and 748 in the control group) attended the six-months follow-up visit. After adjustment for potentially important variables, there were, between the intervention and control group, differences in the mean reduction of body mass index (0.5 vs. 0.2; p < 0.001) and waist circumference (1.6 cm vs. 0.6 cm; p = 0.05), proportion of patients who exercise regularly and those with total cholesterol below 175 mg/dl (64.7% vs. 56.5%; p = 0.001). The reported intake of medications was high in both groups for all the drugs considered with no differences except for statins (98.1% vs. 95.9%; p = 0.029).</p> <p>Conclusions</p> <p>At least in the short term, lifestyle changes among coronary heart disease patients are achievable by intensifying the responsibility of the patient himself by means of a simple and feasible intervention.</p

Temporal relationship of serum markers and tissue damage during acute intestinal ischemia/reperfusion

OBJECTIVE: It is essential to identify a serological marker of injury in order to study the pathophysiology of intestinal ischemia reperfusion. In this work, we studied the evolution of several serological markers after intestinal ischemia reperfusion injury in rats. The markers of non-specific cell damage were aspartate aminotransferase, alanine aminotransaminase, and lactic dehydrogenase, the markers of inflammation were tumor necrosis factor alpha, interleukin-6, and interleukin-1 beta, and the markers of intestinal mucosal damage were intestinal fatty acid binding protein and D-lactate. We used Chius classification to grade the histopathological damage. METHODS: We studied 35 Wistar rats divided into groups according to reperfusion time. The superior mesenteric artery was clamped for 30 minutes, and blood and biopsies were collected at 1, 3, 6, 12, 24, and 48 hours after reperfusion. We plotted the mean ¡ standard deviation and compared the baseline and maximum values for each marker using Student’s t-test. RESULTS: The maximum values of interleukin-1 beta and lactic dehydrogenase were present before the maximal histopathological damage. The maximum tumor necrosis factor alpha and D-lactate expressions coincided with histopathological damage. Alanine aminotransaminase and aspartate aminotransferase had a maximum expression level that increased following the histopathological damage. The maximum expressions of interluken-6 and intestinal fatty acid binding protein were not significantly different from the Sham treated group. CONCLUSION: For the evaluation of injury secondary to acute intestinal ischemia reperfusion with a 30 minute ischemia period, we recommend performing histopathological grading, quantification of D-lactate, which is synthesized by intestinal bacteria and is considered an indicator of mucosal injury, and quantification of tumor necrosis factor alpha as indicators of acute inflammation three hours after reperfusion

Brain atrophy and the risk of futile endovascular reperfusion in acute ischemic stroke

[Background and Purpose]: We aimed to evaluate the impact of brain atrophy on long-term clinical outcome in patients with acute ischemic stroke treated with endovascular therapy, and more specifically, to test whether there are interactions between the degree of atrophy and infarct volume, and between atrophy and age, in determining the risk of futile reperfusion.[Methods]: We studied consecutive patients with acute ischemic stroke with proximal anterior circulation intracranial arterial occlusions treated with endovascular therapy achieving successful arterial recanalization. Brain atrophy was evaluated on baseline computed tomography with the global cortical atrophy scale, and Evans index was calculated to assess subcortical atrophy. Infarct volume was assessed on control computed tomography at 24 hours using the formula for irregular volumes (A×B×C/2). Main outcome variable was futile recanalization, defined by functional dependence (modified Rankin Scale score >2) at 3 months. The predefined interactions of atrophy with age and infarct volume were studied in regression models.[Results]: From 361 consecutive patients with anterior circulation acute ischemic stroke treated with endovascular therapy, 295 met all inclusion criteria. Futile reperfusion was observed in 144 out of 295 (48.8%) patients. Cortical atrophy affecting parieto-occipital and temporal regions was associated with futile recanalization. Total global cortical atrophy score and Evans index were independently associated with futile recanalization in an adjusted logistic regression. Multivariable adjusted regression models disclosed significant interactions between global cortical atrophy score and infarct volume (odds ratio, 1.003 [95%CI, 1.002–1.004], P<0.001) and between global cortical atrophy score and age (odds ratio, 1.001 [95% CI, 1.001–1.002], P<0.001) in determining the risk of futile reperfusion.[Conclusions]: A higher degree of cortical and subcortical brain atrophy is associated with futile endovascular reperfusion in anterior circulation acute ischemic stroke. The impact of brain atrophy on insufficient clinical recovery after endovascular reperfusion appears to be independently amplified by age and by infarct volume.This study has been partially funded by the Spanish Ministry of Science, via FIS projects PI13/02544 and PI16/01396, and through the INVICTUS PLUS research network RD16/0019.Peer reviewe

Oxidative Stress in Wild Boars Naturally and Experimentally Infected with Mycobacterium bovis

Reactive oxygen and nitrogen species (ROS-RNS) are important defence substances involved in the immune response against pathogens. An excessive increase in ROS-RNS, however, can damage the organism causing oxidative stress (OS). The organism is able to neutralise OS by the production of antioxidant enzymes (AE); hence, tissue damage is the result of an imbalance between oxidant and antioxidant status. Though some work has been carried out in humans, there is a lack of information about the oxidant/antioxidant status in the presence of tuberculosis (TB) in wild reservoirs. In the Mediterranean Basin, wild boar (Sus scrofa) is the main reservoir of TB. Wild boar showing severe TB have an increased risk to Mycobacterium spp. shedding, leading to pathogen spreading and persistence. If OS is greater in these individuals, oxidant/antioxidant balance in TB-affected boars could be used as a biomarker of disease severity. The present work had a two-fold objective: i) to study the effects of bovine TB on different OS biomarkers (namely superoxide dismutase (SOD), catalasa (CAT), glutathione peroxidase (GPX), glutathione reductase (GR) and thiobarbituric acid reactive substances (TBARS)) in wild boar experimentally challenged with Mycobacterium bovis, and ii) to explore the role of body weight, sex, population and season in explaining the observed variability of OS indicators in two populations of free-ranging wild boar where TB is common. For the first objective, a partial least squares regression (PLSR) approach was used whereas, recursive partitioning with regression tree models (RTM) were applied for the second. A negative relationship between antioxidant enzymes and bovine TB (the more severe lesions, the lower the concentration of antioxidant biomarkers) was observed in experimentally infected animals. The final PLSR model retained the GPX, SOD and GR biomarkers and showed that 17.6% of the observed variability of antioxidant capacity was significantly correlated with the PLSR X's component represented by both disease status and the age of boars. In the samples from free-ranging wild boar, however, the environmental factors were more relevant to the observed variability of the OS biomarkers than the TB itself. For each OS biomarker, each RTM was defined as a maximum by one node due to the population effect. Along the same lines, the ad hoc tree regression on boars from the population with a higher prevalence of severe TB confirmed that disease status was not the main factor explaining the observed variability in OS biomarkers. It was concluded that oxidative damage caused by TB is significant, but can only be detected in the absence of environmental variation in wild boar