48 research outputs found
The nitrogen source as a tool for weeds management
Los resultados de producción de biomasa, tanto de parte aérea como de raíz, nos muestran las distintas preferencias por una u otra fuente [(nitrato (NO3 -) o amonio(NH4 +)] de nitrógeno (N), así como La influencia de la fuente de N en la respuesta a la dosis (2 mM vs. 0,2 mM) en la zona radicular: Amaranthus viridis y Chenopodium album prefieren el NO3- y no responden a la dosis de NH4+, Conyza bonaeriensis y Solanum nigrum también prefieren NO3- pero responden a la dosis de NH4+, mientras que Sonchus oleraceus prefiere el NH4+ y no responde a la dosis de NO3 -. Igualmente, la fuente de N, y no sólo la dosis de N, tiene una gran repercusión en la relación carbono/nitrógeno (C/N) tanto de la parte aérea como de la raíz. El conjunto de los resultados sugiere que el manejo de la fuente de N en los sistemas agrícolas podría ayudar al manejo de las malas hierbas y con ello a su control, en pro de hacer una mejor optimización de los recursos.The results of biomass production both in terms of shoot and root, show distinct plants preferences for the nitrogen source; Amaranthus viridis and Chenopodium album prefers NO3 - and does not respond to the dose of NH4 +, Conyza bonaeriensis and Solanum nigrum also prefers NO3 - but respond to the dose of NH4 +, and finally Sonchus oleraceus prefers NH4 + over NO3 - and does not respond to the dose of NO3 -. Here, we also show that the source of N has a major role in plant N and C concentration. Overall, these results indicate that N fertilization (source and dose) may be a tool for the management of weeds in agricultural system where the farmer has control over the source of N applied
Holocene evolution of the Xagó dune field (Asturias, NW Spain) reconstructed by means of morphological mapping and ground penetrating radar surveys
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The European Solar Telescope
The European Solar Telescope (EST) is a project aimed at studying the magnetic connectivity of the solar atmosphere, from the deep photosphere to the upper chromosphere. Its design combines the knowledge and expertise gathered by the European solar physics community during the construction and operation of state-of-the-art solar telescopes operating in visible and near-infrared wavelengths: the Swedish 1m Solar Telescope, the German Vacuum Tower Telescope and GREGOR, the French Télescope Héliographique pour l'Étude du Magnétisme et des Instabilités Solaires, and the Dutch Open Telescope. With its 4.2 m primary mirror and an open configuration, EST will become the most powerful European ground-based facility to study the Sun in the coming decades in the visible and near-infrared bands. EST uses the most innovative technological advances: the first adaptive secondary mirror ever used in a solar telescope, a complex multi-conjugate adaptive optics with deformable mirrors that form part of the optical design in a natural way, a polarimetrically compensated telescope design that eliminates the complex temporal variation and wavelength dependence of the telescope Mueller matrix, and an instrument suite containing several (etalon-based) tunable imaging spectropolarimeters and several integral field unit spectropolarimeters. This publication summarises some fundamental science questions that can be addressed with the telescope, together with a complete description of its major subsystems
The European Solar Telescope
The European Solar Telescope (EST) is a project aimed at studying the magnetic connectivity of the solar atmosphere, from the deep photosphere to the upper chromosphere. Its design combines the knowledge and expertise gathered by the European solar physics community during the construction and operation of state-of-the-art solar telescopes operating in visible and near-infrared wavelengths: the Swedish 1m Solar Telescope, the German Vacuum Tower Telescope and GREGOR, the French Télescope Héliographique pour l’Étude du Magnétisme et des Instabilités Solaires, and the Dutch Open Telescope. With its 4.2 m primary mirror and an open configuration, EST will become the most powerful European ground-based facility to study the Sun in the coming decades in the visible and near-infrared bands. EST uses the most innovative technological advances: the first adaptive secondary mirror ever used in a solar telescope, a complex multi-conjugate adaptive optics with deformable mirrors that form part of the optical design in a natural way, a polarimetrically compensated telescope design that eliminates the complex temporal variation and wavelength dependence of the telescope Mueller matrix, and an instrument suite containing several (etalon-based) tunable imaging spectropolarimeters and several integral field unit spectropolarimeters. This publication summarises some fundamental science questions that can be addressed with the telescope, together with a complete description of its major subsystems
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Dietary α‐Linolenic Acid, Marine ω‐3 Fatty Acids, and Mortality in a Population With High Fish Consumption: Findings From the PREvención con DIeta MEDiterránea (PREDIMED) Study
Background: Epidemiological evidence suggests a cardioprotective role of α‐linolenic acid (ALA), a plant‐derived ω‐3 fatty acid. It is unclear whether ALA is beneficial in a background of high marine ω‐3 fatty acids (long‐chain n‐3 polyunsaturated fatty acids) intake. In persons at high cardiovascular risk from Spain, a country in which fish consumption is customarily high, we investigated whether meeting the International Society for the Study of Fatty Acids and Lipids recommendation for dietary ALA (0.7% of total energy) at baseline was related to all‐cause and cardiovascular disease mortality. We also examined the effect of meeting the society's recommendation for long‐chain n‐3 polyunsaturated fatty acids (≥500 mg/day). Methods and Results: We longitudinally evaluated 7202 participants in the PREvención con DIeta MEDiterránea (PREDIMED) trial. Multivariable‐adjusted Cox regression models were fitted to estimate hazard ratios. ALA intake correlated to walnut consumption (r=0.94). During a 5.9‐y follow‐up, 431 deaths occurred (104 cardiovascular disease, 55 coronary heart disease, 32 sudden cardiac death, 25 stroke). The hazard ratios for meeting ALA recommendation (n=1615, 22.4%) were 0.72 (95% CI 0.56–0.92) for all‐cause mortality and 0.95 (95% CI 0.58–1.57) for fatal cardiovascular disease. The hazard ratios for meeting the recommendation for long‐chain n‐3 polyunsaturated fatty acids (n=5452, 75.7%) were 0.84 (95% CI 0.67–1.05) for all‐cause mortality, 0.61 (95% CI 0.39–0.96) for fatal cardiovascular disease, 0.54 (95% CI 0.29–0.99) for fatal coronary heart disease, and 0.49 (95% CI 0.22–1.01) for sudden cardiac death. The highest reduction in all‐cause mortality occurred in participants meeting both recommendations (hazard ratio 0.63 [95% CI 0.45–0.87]). Conclusions: In participants without prior cardiovascular disease and high fish consumption, dietary ALA, supplied mainly by walnuts and olive oil, relates inversely to all‐cause mortality, whereas protection from cardiac mortality is limited to fish‐derived long‐chain n‐3 polyunsaturated fatty acids. Clinical Trial Registration URL: http://www.Controlled-trials.com/. Unique identifier: ISRCTN35739639
Evaluation of appendicitis risk prediction models in adults with suspected appendicitis
Background
Appendicitis is the most common general surgical emergency worldwide, but its diagnosis remains challenging. The aim of this study was to determine whether existing risk prediction models can reliably identify patients presenting to hospital in the UK with acute right iliac fossa (RIF) pain who are at low risk of appendicitis.
Methods
A systematic search was completed to identify all existing appendicitis risk prediction models. Models were validated using UK data from an international prospective cohort study that captured consecutive patients aged 16–45 years presenting to hospital with acute RIF in March to June 2017. The main outcome was best achievable model specificity (proportion of patients who did not have appendicitis correctly classified as low risk) whilst maintaining a failure rate below 5 per cent (proportion of patients identified as low risk who actually had appendicitis).
Results
Some 5345 patients across 154 UK hospitals were identified, of which two‐thirds (3613 of 5345, 67·6 per cent) were women. Women were more than twice as likely to undergo surgery with removal of a histologically normal appendix (272 of 964, 28·2 per cent) than men (120 of 993, 12·1 per cent) (relative risk 2·33, 95 per cent c.i. 1·92 to 2·84; P < 0·001). Of 15 validated risk prediction models, the Adult Appendicitis Score performed best (cut‐off score 8 or less, specificity 63·1 per cent, failure rate 3·7 per cent). The Appendicitis Inflammatory Response Score performed best for men (cut‐off score 2 or less, specificity 24·7 per cent, failure rate 2·4 per cent).
Conclusion
Women in the UK had a disproportionate risk of admission without surgical intervention and had high rates of normal appendicectomy. Risk prediction models to support shared decision‐making by identifying adults in the UK at low risk of appendicitis were identified
Evaluation of the pathogenicity of multiple isolates of Beauveria bassiana (Hypocreales: Clavicipitaceae) on Rhynchophorus ferrugineus (Coleoptera: Dryophthoridae) for the assessment of a solid formulation under simulated field conditions
A solid state formulation of Beauveria bassiana (Balsamo) Vuillemin has been developed for biological control of the Red Palm Weevil (RPW), Rhynchophorus ferrugineus (Olivier, 1790). Two kinds of bioassays (dry conidia and dipping) using 10 isolates from several coleopterans in Mediterranean environments, identified 2 RPW derived isolates (193 and 203) as most pathogenic to RPW larvae and adults (zero survival within first 4–5 d for dry conidia, and 14 and 23 d for dipping bioassays). Isolate 203 (5.1 × 108 ± 1.9 × 108 conidia g-1) was formulated with fragmented date seed into solid granules and tested in palms infested with RPW under semi-field conditions in Feb, Apr/May and Jun of both 2007 and 2008. Beauveria bassiana significantly reduced RPW adult survival with respect to controls in May 2007 and in the Apr/Jun 2008 experiments. Total RPW adult mortality was achieved within 30 days for all B. bassiana treatments, and was associated with increasing numbers of insects with signs of mycosis in 2008 experiments. Beauveria bassiana formulation reduced RPW multiplication in artificially infested palms compared to controls, and a positive correlation between numbers of larvae and time post-infestation was recorded. The suppression of RPW adult populations by B. bassiana persisted for at least 3 months under semi-field conditions. The Beauveria bassiana solid formulation, which induces great adult mortality and persistence in the field, could be applied as a preventive as well as a curative treatment for the integrated management of RPW.En el presente estudio, se describe un procedimiento para el desarrollo de una formulación en estado sólido basada en Beauveria bassiana (Balsamo) Vuillemin para el control biológico del picudo rojo, Rhynchophorus ferrugineus (Olivier, 1790). Al realizar dos tipos de bioensayos (conidios secos e inmersión directa) utilizando diez aislados de diversos coleópteros en ambientes Mediterráneos, se identificaron dos aislados derivados del picudo rojo (193 y 203) como los más patogénicos para los estadios larvarios y adultos del insecto (supervivencia nula en los primeros 4–5 días y 14 y 23 días para bioensayos con conidios secos e inmersión directa respectivamente). El aislado 203 de B. bassiana (5.1 × 108 ± 1.9 × 108 conidios g-1) se formuló en sólido utilizando dátiles fragmentados y se ensayó en palmeras infestadas con el picudo rojo bajo condiciones de semi-campo en los meses de Febrero, Abril/Mayo y Junio de 2007 y 2008. Beauveria bassiana redujo significativamente la supervivencia de los insectos adultos con respecto a los controles en los experimentos de Mayo de 2007 y Abril/Junio 2008. Se alcanzó la mortalidad completa de los adultos del picudo rojo en 30 días para todos los tratamientos con B. bassiana y lo que se correlacionó con el incremento del número de insectos con signos de micosis para los ensayos de 2008. El formulado de B. bassiana redujo la multiplicación del insecto en palmeras infestadas artificialmente con respecto a los controles, registrándose una correlación positiva entre el número de larvas y el tiempo de infestación posterior. La capacidad del formulado de B. bassiana para suprimir las poblaciones de insectos adultos tuvo una persistencia de al menos tres meses bajo condiciones de semicampo. El formulado sólido de B. bassiana, que ha generado una alta mortalidad en adultos así como una elevada persistencia, podría utilizarse tanto en tratamientos preventivos como curativos en el manejo integrado del picudo rojo.This research was financed with the INIA (TRT2006-0016-C07-02) and PETRI (PET2007-0469-01) project grants from the Spanish Ministry of Science and Education, and with a grant from Generalitat Valenciana to B. Güerri-Agulló (BFPI06/493). Jorge Ricaño was supported by a grant from the Mexico’s National Council of Science and Technology (CONACYT)