1,461 research outputs found

    Effect of the nature of exogenous organic matter on pesticide sorption by the soil

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    A study was carried out on the sorption of two sparingly water-soluble pesticides (diazinon and linuron) by a sandy loam soil modified with different exogenous organic materials (EOMs) containing humic like substances: city refuse compost (CRC), peat (P), commercial humic acid (HA), liquid humic acid (LHA) extracted from leonardite and two (non humic) model compounds (surfactants): tetradecyltrimethylammonium bromide (TDTMA) and sodium dodecyl sulphate (SDS) before and after 2 and 8 months incubation periods with the soil. In all cases, the isotherms fitted the Freundlich sorption equation (x/m=KCen), generally with r2 values greater than 0.99. The value of the sorption constant K for the natural soil was 8.81 for diazinon and 2.29 for linuron. These values increased significantly for EOM modified soils with respect to natural soil, with the exception of the samples modified with SDS and LHA, in which cases they decreased, possibly due to the micellar properties of these compounds. Incubation of EOMs with soil increased their sorption capacity: the Koc values were increased proportionally to the incubation time for both pesticides and for all treatments carried out. Accordingly, the sorption capacity of hydrophobic pesticides increases with the degree of evolution in the soil of EOMs with humic type compounds, possibly due, among other causes, to the increase in the EOMs colloidal properties and the modifications occurring in the hydrophobic- hydrophilic characteristics of the soil surfaces. The main conclusion is that application to the soil of solid carbon rich wastes, especially those with a high degree of maturity, may offer an important strategy for reducing pesticide leaching, and for eliminating pesticide residues from soil with the use of liquid humic acids.Peer reviewe

    Effect of the nature of exogenous organic matter on pesticide sorption by the soil

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    A study was carried out on the sorption of two sparingly water-soluble pesticides (diazinon and linuron) by a sandy loam soil modified with different exogenous organic materials (EOMs) containing humic like substances: city refuse compost (CRC), peat (P), commercial humic acid (HA), liquid humic acid (LHA) extracted from leonardite and two (non humic) model compounds (surfactants): tetradecyltrimethylammonium bromide (TDTMA) and sodium dodecyl sulphate (SDS) before and after 2 and 8 months incubation periods with the soil. In all cases, the isotherms fitted the Freundlich sorption equation (x/m=KCen), generally with r2 values greater than 0.99. The value of the sorption constant K for the natural soil was 8.81 for diazinon and 2.29 for linuron. These values increased significantly for EOM modified soils with respect to natural soil, with the exception of the samples modified with SDS and LHA, in which cases they decreased, possibly due to the micellar properties of these compounds. Incubation of EOMs with soil increased their sorption capacity: the Koc values were increased proportionally to the incubation time for both pesticides and for all treatments carried out. Accordingly, the sorption capacity of hydrophobic pesticides increases with the degree of evolution in the soil of EOMs with humic type compounds, possibly due, among other causes, to the increase in the EOMs colloidal properties and the modifications occurring in the hydrophobic- hydrophilic characteristics of the soil surfaces. The main conclusion is that application to the soil of solid carbon rich wastes, especially those with a high degree of maturity, may offer an important strategy for reducing pesticide leaching, and for eliminating pesticide residues from soil with the use of liquid humic acids.Peer reviewe

    Modelo de Interoperabilidad Basado en Metadatos (MIBM)

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    Un objetivo fundamental de las Infraestructuras de Datos Espaciales (IDE) es dotar de interoperabilidad a los sistemas que han de intercambiar datos geográficos. La interoperabilidad es, en sí misma, un objetivo, así como lo es el análisis y la medida del grado de interoperabilidad entre dos sistemas. Tanto en el campo de los Sistemas de Información Geográfica (SIG) [1] como en el de la ingeniería del software [2] o el de las organizaciones, se ha estudiado la interoperabilidad y se han propuesto modelos de la misma para los sistemas, las organizaciones y los sistemas de sistemas. En el contexto de las IDE no se ha desarrollado apenas investigación relacionando la interoperabilidad y los metadatos de la Información Geográfica. Los objetivos de este documento son: presentar un modelo de interoperabilidad de 7 niveles (técnica, sintáctica, semántica, pragmática, dinámica, conceptual y organizacional) así como los resultados de analizar las aportaciones, en términos de interoperabilidad, de los ítems contenidos en ISO19115 [3] según dicho modelo. Se concluye este trabajo enumerando una serie de conclusiones preliminares obtenidas de la validación

    Análisis cualitativo de la percepción del profesorado y de las familias sobre los conflictos y las conductas agresivas entre escolares

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    La conducta agresiva se define como aquella conducta que pretende causar daño físico y/o psicológico y en situaciones extremas, puede llegar a ser destructiva para la persona objeto de la agresión. El artículo muestra dos estudios realizados con profesores y padres de alumnos pertenecientes a los ciclos de educación primaria, educación secundaria y bachillerato. El primer estudio muestra la percepción del profesorado respecto de las conductas agresivas ejercidas en el centro escolar, el comportamiento de los alumnos ante ellas, las consecuencias que se derivan y las propuestas de mejora. El segundo, dirigido a las familias, indica en qué medida conocen las situaciones más o menos agresivas que ejercen o son ejercidas sobre sus hijos, las posibles causas de las agresiones y las alternativas de solución. Los resultados obtenidos indican que los profesores perciben que las agresiones acontecidas en el centro escolar son resultado de las características físicas y personales tanto del agresor como de la víctima, produciéndose, la mayoría de ellas, en situaciones de juego. Los padres, por el contrario, al menos, cuando su hijo desempeña el rol de víctima, desconocen la causa de la agresión, mientras que cuando actúa como agresor, consideran que es una respuesta a una situación violenta anterior. Sin embargo, padres y profesores manifiestan que el entrenamiento en habilidades prosociales y el incremento de la interacción entre familia y escuela son las claves para afrontar el problema

    Diferencias en los niveles de motivación por sexo, curso y tipo de centro educativo en el aprendizaje estratégico de la lengua extranjera

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    This research shows an analysis of the main motivational models applied to foreign language acquisition and is aimed at identifying the motivational variables that present the highest influence in the strategic acquisition of a foreign language. The questionnaire Autoeficacia y Motivación Académica was given to a sample of 564 subjects (309 males and 254 females) who were studying 3rd (41.030%) and 4th (28.597%) of Secondary Education and 1st year of High School (30.373%) in two schools of the Comunidad de Madrid (41.7% in a public school and 58.3% in a private school). Results show that values of items related to instrumental motivation are the highest. Females obtained higher results in all factors studied in the same way as the private school with the exception of the variable Perceived Ability which was higher in the public school.La investigación realiza una revisión de los principales modelos motivacionales aplicados al aprendizaje de idiomas y se centra en la identificación de aquellas variables motivacionales que más inciden en el aprendizaje estratégico de una lengua extranjera. Para ello, se aplicó el Cuestionario de Autoeficacia y Motivación Académica a una muestra de 564 sujetos (309 varones y 254 mujeres) pertenecientes a 3.º (41,030%) y 4.º (28,597%) de ESO y 1.º de Bachillerato (30,373%) de dos centros educativos de la CM (41,7%, centro público y 58,3%, centro privado). Los resultados muestran que las puntuaciones en los ítems que indican motivación instrumental (motivos profesionales y de reconocimiento social) son los más altos. Las mujeres obtienen puntuaciones más altas en todos los factores así como el centro privado, salvo en la variable Habilidad Percibida, que es superior en el centro público

    Association between knowledge and attitudes towards advance directives in emergency services

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    Background: implementing the routine consultation of patient advance directives in hospital emergency departments and emergency medical services has become essential, given that advance directives constitute the frame of reference for care personalisation and respect for patients' values and preferences related to healthcare. The aim of this study was to assess the levels and relationship of knowledge and attitudes of nursing and medical professionals towards advance directives in hospital emergency departments and emergency medical services, and to determine the correlated and predictor variables of favourable attitudes towards advance directives. Methods: observational, descriptive, and cross-sectional study. The study was conducted in the emergency department of a second-level hospital and in the emergency medical service. Data collection was performed from January 2019 to February 2020. The STROBE guidelines were followed for the preparation of the study. Results: a total of 173 healthcare professionals responded to the questionnaire. Among them, 91.3% considered that they were not sufficiently informed about advance directives, and 74% acknowledged not having incorporated them into their usual practice. Multinomial analysis indicated a statistically significant relationship between the variable emergency medical service and having more favourable attitudes towards consulting the advance directives in their practical application (OR 2.49 [95% CI 1.06-5.88]; p = 0.037) and compliance in complex scenarios (OR 3.65 [95% CI 1.58 - 8.41]; p = 0.002). Working the afternoon and night shift was a predictor variable for obtaining a higher score with respect to attitudes in complex scenarios. Conclusion: there is an association between the level of knowledge that nursing and medical professionals have about advance directives and the scores obtained on the attitude scales at the time of practical implementation and in complex scenarios. This shows that the more knowledge professionals have, the more likely they are to consult patients' advance directives and to respect their wishes and preferences for care and/or treatment

    Targeting the TWEAK–Fn14 pathway prevents dysfunction in cardiac calcium handling after acute kidney injury

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    Heart and kidney have a closely interrelated pathophysiology. Acute kidney injury (AKI) is associated with significantly increased rates of cardiovascular events, a relationship defined as cardiorenal syndrome type 3 (CRS3). The underlying mechanisms that trigger heart disease remain, however, unknown, particularly concerning the clinical impact of AKI on cardiac outcomes and overall mortality. Tumour necrosis factor-like weak inducer of apoptosis (TWEAK) and its receptor fibroblast growth factor-inducible 14 (Fn14) are independently involved in the pathogenesis of both heart and kidney failure, and recent studies have proposed TWEAK as a possible therapeutic target; however, its specific role in cardiac damage associated with CRS3 remains to be clarified. Firstly, we demonstrated in a retrospective longitudinal clinical study that soluble TWEAK plasma levels were a predictive biomarker of mortality in patients with AKI. Furthermore, the exogenous application of TWEAK to native ventricular cardiomyocytes induced relevant calcium (Ca2+) handling alterations. Next, we investigated the role of the TWEAK–Fn14 axis in cardiomyocyte function following renal ischaemia–reperfusion (I/R) injury in mice. We observed that TWEAK–Fn14 signalling was activated in the hearts of AKI mice. Mice also showed significantly altered intra-cardiomyocyte Ca2+ handling and arrhythmogenic Ca2+ events through an impairment in sarcoplasmic reticulum Ca2+-adenosine triphosphatase 2a pump (SERCA2a) and ryanodine receptor (RyR2) function. Administration of anti-TWEAK antibody after reperfusion significantly improved alterations in Ca2+ cycling and arrhythmogenic events and prevented SERCA2a and RyR2 modifications. In conclusion, this study establishes the relevance of the TWEAK–Fn14 pathway in cardiac dysfunction linked to CRS3, both as a predictor of mortality in patients with AKI and as a Ca2+ mishandling inducer in cardiomyocytes, and highlights the cardioprotective benefits of TWEAK targeting in CRS3This work was mainly supported by projects from the Instituto de Salud Carlos III (ISCIII) (PI20/00763, PI20/01482, CPII20/00022, FI18/00261, FI21/00212, CD19/00029, IFEQ21/00012, PI19/00588, PI22/00469) and co-funded by the European Union, Ministerio de Universidades (FPU20/03005), Ministerio de Ciencia e Innovaci on (RYR2019-026916-I), the Education and Research Council of Madrid (PEJ-2021- AI/SAL-21426), Biomedicine Network Comunidad de Madrid (P2022/BMD-7223 CIFRA_COR-CM), Spanish Network in Inflammasoma and Pyroptosis in Chronic Disease and Cancer (RED2022-134511-T), and the Spanish Society of Nephrology SEN/SENEFRO Foundatio

    Contribución al conocimiento de la flora de Andalucía: citas novedosas e interesantes de la provincia de Almería

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    Contribution to the knowledge about Andalusian flora: new and interesting cites of the Almería province.Palabras clave. Corología, Isla de Alborán, sureste ibérico, xenófitas.Key words. Corology, Alborán Island, South-Eastern Iberian Peninsula, xenophytes

    Single hadron response measurement and calorimeter jet energy scale uncertainty with the ATLAS detector at the LHC

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    The uncertainty on the calorimeter energy response to jets of particles is derived for the ATLAS experiment at the Large Hadron Collider (LHC). First, the calorimeter response to single isolated charged hadrons is measured and compared to the Monte Carlo simulation using proton-proton collisions at centre-of-mass energies of sqrt(s) = 900 GeV and 7 TeV collected during 2009 and 2010. Then, using the decay of K_s and Lambda particles, the calorimeter response to specific types of particles (positively and negatively charged pions, protons, and anti-protons) is measured and compared to the Monte Carlo predictions. Finally, the jet energy scale uncertainty is determined by propagating the response uncertainty for single charged and neutral particles to jets. The response uncertainty is 2-5% for central isolated hadrons and 1-3% for the final calorimeter jet energy scale.Comment: 24 pages plus author list (36 pages total), 23 figures, 1 table, submitted to European Physical Journal
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