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Closed surjective ideals of multilinear operators and interpolation
No full textIn this paper we introduce a function for multilinear operators that can be considered as an extension of the so-called outer measure associated to a linear operator ideal. We prove that it allows to characterize the operators that belong to a closed surjective ideal of multilinear operators as those having measure equal to zero. We also obtain some interpolation formulas for this new measure. As a consequence we deduce interpolation results for arbitrary closed surjective ideals of multilinear operators which recover, in particular, different results previously established in the literature.The authors would like to thank the referees for their useful comments which have led to improve the paper. A. Manzano was supported in part by the Ministerio de Economía, Industria y Competitividad and FEDER under project MTM2017-84058-P. P. Rueda and E. A. Sánchez-Pérez were supported in part by the Ministerio de Economía, Industria y Competitividad and FEDER under project MTM2016-77054-C2-1-P
Synthesis, Crystal Structure, Spectroscopic Characterization, DFT Calculations and Cytotoxicity Assays of a New Cu(II) Complex with an Acylhydrazone Ligand Derived from Thiophene
No full textA new Cu(II) complex is synthetized by the reaction of copper nitrate and a N-acylhydrazone ligand obtained from the condensation of o-vanillin and 2-thiophecarbohydrazide (H2L). The solid-state structure of [Cu(HL)(H2O)](NO3)·H2O, or CuHL for simplicity, was determined by X-ray diffraction. In the cationic complex, the copper center is in a nearly squared planar environment with the nitrate interacting as a counterion. CuHL was characterized by spectroscopic techniques, including solid-state FTIR, Raman, electron paramagnetic resonance (EPR) and diffuse reflectance and solution UV-Vis electronic spectroscopy. Calculations based on the density functional theory (DFT) assisted the interpretation and assignment of the spectroscopic data. The complex does not show relevant antioxidant activity evaluated by the radical cation of 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) method, being even less active than the free ligand as a radical quencher. Cytotoxicity assays of CuHL against three human tumor cell lines, namely MG-63, A549 and HT-29, revealed an important enhancement of the effectiveness as compared with both the ligand and the free metal ion. Moreover, its cytotoxic effect was remarkably stronger than that of the reference metallodrug cisplatin in all cancer cell lines tested, a promissory result in the search for new metallodrugs of essential transition metals.This research was funded by CONICET-CCT- La Plata (PIP 0651 and 034), ANPCyT (PICT 2016-1574) and UNLP (11/X041, 11/X837 and 11/X857), Argentina, and also by Consejería de Educación of Junta de Castilla y León BU022G18, Junta de Castilla y León and FEDER BU291P18 and BU049P20, Ministerio de Economía y Competitividad, CTQ2016-75023-C2-1-P, and Ministerio de Ciencia, Innovación y Universidades, CTQ(QMC) RED2018-102471-T, MultiMetDrugs Network (Spain)
"Asylum of Incurably Lazy and Depraved Men": The Philippines as a Space of Degenerate Masculinity in the Late Fiction of Emilia Pardo Bazán
No full textRelationship between Autism Spectrum Disorder and Pesticides: A Systematic Review of Human and Preclinical Models
No full textAutism spectrum disorder (ASD) is a complex set of neurodevelopmental pathologies characterized by impoverished social and communicative abilities and stereotyped behaviors. Although its genetic basis is unquestionable, the involvement of environmental factors such as exposure to pesticides has also been proposed. Despite the systematic analyses of this relationship in humans, there are no specific reviews including both human and preclinical models. The present systematic review summarizes, analyzes, and discusses recent advances in preclinical and epidemiological studies. We included 45 human and 16 preclinical studies. These studies focused on Organophosphates (OP), Organochlorine (OC), Pyrethroid (PT), Neonicotinoid (NN), Carbamate (CM), and mixed exposures. Preclinical studies, where the OP Chlorpyrifos (CPF) compound is the one most studied, pointed to an association between gestational exposure and increased ASD-like behaviors, although the data are inconclusive with regard to other ages or pesticides. Studies in humans focused on prenatal exposure to OP and OC agents, and report cognitive and behavioral alterations related to ASD symptomatology. The results of both suggest that gestational exposure to certain OP agents could be linked to the clinical signs of ASD. Future experimental studies should focus on extending the analysis of ASD-like behaviors in preclinical models and include exposure patterns similar to those observed in human studies.he study was supported by grants from the Spanish Goverment (Ministerio de Economía y Competitividad, Ministerio de Ciencia, Innovación y Universidades and Instituto Mixto de Investigación-Escuela Nacional de Sanidad (IMIENS)) and the Fondo Europeo de Desarrollo Regional (MINECO-FEDER) [Grant numbers: PSI2017-86847-C2-1-R MINECO-FEDER, PSI2017-86847-C2-2-R, PSI2017-86396-P, PSI2017-90806-REDT, PSI2013-45924-P, PSI2017-83038-P, PSI2017-83893-R, MINECO PSI2017-86396-P and IMIENS: PIC-IMIENS-2018-003]
Use of Computed Tomography Scan Technology to Explore the Porosity of Concrete: Scientific Possibilities and Technological Limitations
No full textThis paper shows the scientific possibilities of computed tomography for the study of concrete porosity. The enormous technological advances in computed tomography equipment used in materials research, with increasingly higher energy, better resolution and smaller pixel size will allow, in the near future, viewing pore sizes that are currently unthinkable, competing in resolution with the traditional techniques of mercury porosimetry and nitrogen adsorption. The challenge at that time (and to a lesser extent today) will be how to extract as much information as possible from the large amount of data provided by computed tomography equipment. In this article, through the study of six cubic specimens of 40 mm sides, different techniques of extraction and presentation of the information are shown, which help us to better understand the characterization of the morphology and distribution of the pores inside the concrete matrix. This information is essential to understand some of the macroscopic responses of the concrete.This research was funded by the Ministerio de Economía y Competitividad, Gobierno de España (Spain); grant number PID2019-110928RB-C32
Double fingerprint characterization of uracil and 5-fluorouracil
No full textTime Resolved Raman spectroelectrochemistry (TR-Raman-SEC) has been used for the first time to obtain two different Raman spectra of one single analyte in the same experiment. This double detection has been accomplished thanks to the use of electrochemical surface enhanced Raman scattering (EC-SERS) and electrochemical surface oxidation enhanced Raman scattering (EC-SOERS) in the same experiment. These two Raman enhancement phenomena can provide a broad insight into the interaction between analyte and substrate surface when they are combined. To prove the possibilities of this methodology, a Raman spectroelectrochemistry study of uracil (U) and 5-fluorouracil (5-FU), two analytes with relevance in medicine and biochemistry, have been performed. Density functional theory (DFT) calculations has been carried out to shed more light on the interaction of these molecules with silver substrates in acidic media.Authors acknowledge the financial support from Ministerio de Economía, y Competitividad (Grant CTQ2017–83935-R-AEI/FEDERUE), Junta de Castilla y León (Grant BU297P18, Grant BU087G19, and Grant BU263P18) and Ministerio de Ciencia, Innovación y Universidades (Grant RED2018–102412-T and Grant PID2019–111215RB-I00). W. Ch. thanks JCyL for his postdoctoral fellowship (Grant BU297P18). S.H. thanks JCyL and European Social Fund for her predoctoral fellowship. M.P-E. thanks JCyL, the European Social Fund and the Youth Employment initiative and JCyL and European Social Fund for his predoctoral fellowship. This research has made use of the high-performance computing resources of the Castilla y León Supercomputing Center (SCAYLE, https://www.scayle.es), financed by FEDER (Fondo Europeo de Desarrollo Regional). Jorge Gonzalez is acknowledged for his help in the laboratory whose contract was founded by JCyL, the European Social Fund and the Youth Employment Initiative
Validity evidence for a measure of motivation for science
No full textEn los últimos años se ha detectado un descenso en las vocaciones
científicas del alumnado. El modelo expectativa-valor se postula como uno de
los enfoques teóricos más útiles para comprender las motivaciones académicas;
sin embargo, estudios recientes sugieren la necesidad de añadir un tercer
constructo, denominado coste. Dado que no existen investigaciones que apoyen
esta reconceptualización en la población española, el presente estudio expone el
diseño y el análisis de las propiedades psicométricas de un nuevo instrumento
enfocado a medir la motivación por la asignatura de Ciencias de la Naturaleza
en Educación Primaria y aporta datos de referencia para esta etapa educativa.
Se trata de una investigación de tipo instrumental, con una muestra no
probabilística de conveniencia compuesta por 339 estudiantes de 3º a 6º curso,
proveniente de nueve centros educativos de la provincia de Burgos. El análisis
factorial confirmatorio arrojó niveles de bondad de ajuste óptimos para la
estructura factorial compuesta por tres factores: expectativas de éxito, creencias
de valor, y coste. Las matrices de coeficientes estandarizados y de correlaciones
entre constructos proporcionaron evidencias de validez convergentes y
discriminantes. Un análisis correlacional con seis dimensiones actitudinales de
afinidad teórica aportó evidencias de validez concurrente. Asimismo, los tres
factores presentaron una fiabilidad interna adecuada, atendiendo a los índices
Alfa de Cronbach y Omega de McDonald. Finalmente, se han identificado bajos
niveles de expectativas de éxito y creencias de valor, sin diferencias significativas según el género o el nivel escolar. Estos hallazgos ofrecen apoyo empírico para el modelo teórico expectativas-valor-coste y presentan un instrumento oportuno, pertinente y psicométricamente válido y confiable que permite el desarrollo de futuras investigaciones. Además, resaltan la necesidad de desarrollar intervenciones educativas desde etapas elementales para fomentar la motivación por las ciencias de la naturaleza.Lately, a decline in the scientific vocations of students has been identified. The expectancy-value model is postulated as one of the most useful theoretical frameworks for understanding academic motivations; however, recent studies suggest the need to add a third construct, called cost. Since there is a lack of research supporting this reconceptualization in the Spanish population, this investigation presents the design and psychometric analysis of a new instrument focused on measuring motivation for school science subjects in elementary education and provides reference data for this educational stage. The research adopted an instrumental design, with a non-probabilistic convenience sample of 339 students from 3rd to 6th grades, drawn from nine schools in the province of Burgos. The confirmatory factor analysis yielded optimal goodness-of-fit levels for the factorial structure composed of three factors: expectancies of success, task value and cost. Matrices of standardized coefficients and correlations between constructs provided evidence of convergent and discriminative validity. A correlational analysis with six attitudinal dimensions of theoretical convergence provided robust evidence of concurrent validity. Likewise, the three factors possessed adequate internal reliability, according to Cronbach’s alpha and McDonald’s Omega indices. Finally, low levels of expectancies of success expectancies and value beliefs were identified, with no significant differences according to gender or school level. These findings provide empirical support for the expectations-value-cost theoretical model and present a timely, relevant and psychometrically valid and reliable instrument that allows for the development of future research. In addition, they highlight the need to develop educational interventions from elementary stages to foster motivation for the natural sciences
Los anticipos de caja fija como vía de escape de la regulación antifraude del contrato menor
No full textLos contratos menores han sido una de las formas de contratación más utilizadas y han
tenido una especial incidencia en el contexto de la actividad administrativa desarrollada por
las entidades locales. La sencillez en el procedimiento y la rapidez de ejecución han sido
características muy valiosas para su extensa utilización, pero también han constituido una
puerta abierta para actuar al margen de los principios que inspiran la contratación pública
como son la publicidad, la transparencia, la no discriminación así como la eficiencia en la
utilización de los recursos públicos
Estimation of baseline levels of bacterial community tolerance to Cr, Ni, Pb, and Zn in unpolluted soils, a background for PICT (pollution-induced community tolerance) determination
No full textThe PICT method (pollution-induced community tolerance) can be used to assess whether changes in soil microbial response are due to heavy metal toxicity or not. Microbial community tolerance baseline levels can, however, also change due to variations in soil physicochemical properties. Thirty soil samples (0–20 cm), with geochemical baseline concentrations (GBCs) of heavy metals and from five different parent materials (granite, limestone, schist, amphibolite, and serpentine), were used to estimate baseline levels of bacterial community tolerance to Cr, Ni, Pb, and Zn using the leucine incorporation method. General equations (n = 30) were determined by multiple linear regression using general soil properties and parent material as binary variables, explaining 38% of the variance in log IC50 (concentration that inhibits 50% of bacterial growth) values for Zn, with 36% for Pb, 44% for Cr, and 68% for Ni. The use of individual equations for each parent material increased the explained variance for all heavy metals, but the presence of a low number of samples (n = 6) lead to low robustness. Generally, clay content and dissolved organic C (DOC) were the main variables explaining bacterial community tolerance for the tested heavy metals. Our results suggest that these equations may permit applying the PICT method with Zn and Pb when there are no reference soils, while more data are needed before using this concept for Ni and Cr.Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. This study has been funded by the Spanish Ministry of Economy and Competitiveness through the project CTM2015-73422-JIN (FEDER Funds). David Fernández-Calviño holds a Ramón y Cajal contract (RYC-2016–20411) financed by the Spanish Ministry of Economy, Industry and Competitiveness. Claudia Campillo-Cora holds a predoctoral fellowship financed by Xunta de Galicia (ED481A-2020/084). Diego Soto-Gómez was supported by a postdoctoral fellowship from the Spanish Ministry of Education “Juan de la Cierva Formación (FJC2019-039176-I).
Profesor digital del siglo XXI
No full textEl desarrollo tecnológico incide directamente en el ámbito educativo al considerar la escuela
como “un reflejo de la sociedad” que integra los nuevos escenarios del siglo XXI. Los estudios
actuales reflejan la necesidad de una formación basada en un currículo por competencias. Este
enfoque coincide con la concepción planteada por un cambio en la sociedad de la información.
De este modo, se considera una prioridad tener presente estas situaciones problemáticas al
abordar la educación del Siglo XXI