93 research outputs found
Mössbauer study of iron gall inks on historical documents
AL designed and coordinated the practical and scientific work, was involved
in the evaluation and interpretation of the data and wrote various drafts of
the paper. FEW designed and coordinated the practical and scientific work,
performed the Mössbauer spectroscopy, evaluated and interpreted the
data and wrote the final version of the manuscript. MD carried out the pH
measurements of the papers and determined the nature of the papers and
gave valuable hints to research on historical documents. TE provided the
fragments of the two Spanish documents. JLPP proposed this investigation
and gave valuable hints on the documents. All authors read and approved the
final manuscript.Iron gall ink was used in the Western world as a permanent writing material already in late Roman times and throughout the Middle Ages, until it became obsolete in the twentieth century. There is much interest in experimental methods to determine the state of the ink and its degradation products on historical documents. Mossbauer spectroscopy with Fe-57 is such a method, and it has the particular advantage to be sensitive to the chemical bonding of iron, but this method has only rarely been applied to historical documents. In this paper we present Mossbauer data for two damaged documents from a Library in Granada and a handwritten German book from the eighteenth century. In addition to the inked parts of the manuscripts, ink-free parts were studied to determine the amount and chemical state of the iron in the papers. These new results are discussed in the context of previously published Mossbauer data. In one of the investigated documents Fe(II)-oxalate, FeC2O4 center dot 2H(2)O, was observed. The assignment of the various Fe3+ sites in the different documents is rather difficult and often there is a superposition of various species. Known forms of iron gallate are definitely not present on the inked papers. The observed ferric species can be remains of Fe3+ polyphenol complexes of the ink, complexes of Fe3+ with degradation products of the cellulose of the paper or gum arabic, or very small iron oxide or hydroxide nanoparticles
Clima organizacional y engagement laboral en docentes de nivel secundaria en la región Junín
Objective. To establish the relationship between organizational climate and work engagement in secondary school teachers in the Junín region (Peru). Methods. The study had a quantitative approach, basic type for its purpose, correlational level and cross-sectional and correlational design. Two instruments were used: the organizational climate questionnaire which consisted of 23 items and whose dimensions were leadership, communication and motivation; and the work engagement questionnaire which consisted of 16 items and 3 dimensions: vigor, dedication and absorption. The sampling technique was non-probabilistic by convenience, and the sample consisted of 126 secondary school teachers. Results. 84.1 % perceived that the organizational climate was good and 69 % considered that work engagement was high. The hypothesis test confirms the significant relationship between both variables, since the p-value found was 0.001 and the Kendall's tau-b correlation strength was 0.363, which indicates that there is a medium-low correlation. Conclusion. There is sufficient evidence to affirm that the organizational climate has a lower level of incidence on work engagement, which, however, could be greater if educational institutions do not consider preventive measures.Objetivo. Establecer la relación entre clima organizacional y engagement laboral en docentes de educación secundaria en la región Junín (Perú). Métodos. El estudio tuvo un enfoque cuantitativo, tipo básico por su finalidad, nivel correlacional y diseño transversal y correlacional. Se emplearon dos instrumentos: el cuestionario de clima organizacional que constó de 23 ítems y cuyas dimensiones fueron liderazgo, comunicación y motivación; y el de engagement laboral que constó de 16 ítems y 3 dimensiones: vigor, dedicación y absorción. La técnica de muestreo fue no probabilística por conveniencia, y la muestra fue de 126 docentes de educación secundaria. Resultados. El 84,1 % percibió que el clima organizacional es bueno y el 69 % considera que el engagement laboral es alto. La prueba de hipótesis confirma la relación significativa entre ambas variables, puesto que el p-valor hallado fue de 0,001 y la fuerza de correlación tau-b de Kendall de 0,363, lo cual señala que existe correlación media-baja. Conclusión. Existen evidencias suficientes para afirmar que el clima organizacional tiene un nivel de incidencia menor en el engagement laboral, el cual, sin embargo, podría ser mayor si las instituciones educativas no consideran medidas preventivas
Buenas prácticas de transferencia del conocimiento en la Universidad de Córdoba
La iniciativa consiste en proporcionar la materia prima. El proyecto, que se ha realizado con cerdos y ha tenido una duración de tres años, demuestra que la administración de Cardiotrofina-1 en el transplante hepático incrementa la supervivencia del animal, mejora su función cardiaca, respiratoria y renal, y también consigue reducir el daño hepatocelecuar y el estrés oxidativo y nitrosativo en el injerto
The karst site of Las Palomas (Guadalteba County, Málaga, Spain): A preliminary study of its MiddleeLate Pleistocene archaeopaleontological record
Cleaning works in the cave of Las Palomas in Teba (Málaga, Spain), developed by the Guadalteba
Consortium, have provided a number of lithic tools and knapping products that may be ascribed to the
Mode III technotypological tradition as well as remains of a number of large mammal species typical of
MiddleeLate Pleistocene times. Topographic measurements help to place this ancient cave within a karst
landform. This discovery opens up new perspectives in the research on the Neanderthal groups that
inhabited the valleys of Guadalteba and Turón rivers in the middle basin of the Guadalhorce River, and
thus in the southern region of the Iberian Peninsula
Hispanic Latin America, Spain and the Spanish-speaking Caribbean: A rich source of reference material for public health, epidemiology and tropical medicine
There is a multiplicity of journals originating in Spain and the Spanish-speaking countries of Latin America and the Caribbean (SSLAC) in the health sciences of relevance to the fields of epidemiology and public health. While the subject matter of epidemiology in Spain shares many features with its neighbours in Western Europe, many aspects of epidemiology in Latin America are particular to that region. There are also distinctive theoretical and philosophical approaches to the study of epidemiology and public health arising from traditions such as the Latin American social medicine movement, of which there may be limited awareness. A number of online bibliographic databases are available which focus primarily on health sciences literature arising in Spain and Latin America, the most prominent being Literatura Latinoamericana en Ciencias de la Salud (LILACS) and LATINDEX. Some such as LILACS also extensively index grey literature. As well as in Spanish, interfaces are provided in English and Portuguese. Abstracts of articles may also be provided in English with an increasing number of journals beginning to publish entire articles written in English. Free full text articles are becoming accessible, one of the most comprehensive sources being the Scientific Electronic Library Online (SciELO). There is thus an extensive range of literature originating in Spain and SSLAC freely identifiable and often accessible online, and with the potential to provide useful inputs to the study of epidemiology and public health provided that any reluctance to explore these resources can be overcome. In this article we provide an introduction to such resources
The Mars Environmental Dynamics Analyzer, MEDA. A Suite of Environmental Sensors for the Mars 2020 Mission
86 pags., 49 figs., 24 tabs.NASA’s Mars 2020 (M2020) rover mission includes a suite of sensors to monitor current environmental conditions near the surface of Mars and to constrain bulk aerosol properties from changes in atmospheric radiation at the surface. The Mars Environmental Dynamics Analyzer (MEDA) consists of a set of meteorological sensors including wind sensor, a barometer, a relative humidity sensor, a set of 5 thermocouples to measure atmospheric temperature at ∼1.5 m and ∼0.5 m above the surface, a set of thermopiles to characterize the thermal IR brightness temperatures of the surface and the lower atmosphere. MEDA adds a radiation and dust sensor to monitor the optical atmospheric properties that can be used to infer bulk aerosol physical properties such as particle size distribution, non-sphericity, and concentration. The MEDA package and its scientific purpose are described in this document as well as how it responded to the calibration tests and how it helps prepare for the human exploration of Mars. A comparison is also presented to previous environmental monitoring payloads landed on Mars on the Viking, Pathfinder, Phoenix, MSL, and InSight spacecraft.This work has been funded by the Spanish Ministry of Economy and Competitiveness, through the projects No. ESP2014-54256-C4-1-R (also -2-R, -3-R and -4-R) and AYA2015-65041-P; Ministry of Science, Innovation and Universities, projects No. ESP2016-79612-C3-1-R (also -2-R and -3-R),
ESP2016-80320-C2-1-R, RTI2018-098728-B-C31 (also -C32 and -C33) and RTI2018-099825-B-C31; Instituto Nacional de Técnica Aeroespacial; Ministry of Science and Innovation’s Centre for the Development of Industrial Technology; Grupos Gobierno Vasco IT1366-19; and European Research Council Consolidator Grant no 818602. The US co-authors performed their work under sponsorship from NASA’s Mars 2020 project, from the
Game Changing Development program within the Space Technology Mission Directorate and from the Human Exploration and Operations Directorate
Social times, reproduction and social inequality at work : contrasts and comparative perspectives between countries
Production of INCASI Project H2020-MSCA-RISE-2015 GA 691004If the focus is placed specifically on the problem of work and family, the daily life of people and their use of time are a main problem. This time is expressed in both freely available time, which is related to activities, and time of the productive and reproductive sphere. This chapter considers work in a broad sense and takes into account the sexual division of labour. Specifically, this chapter will explore transformations in time use and social inequality in unpaid work. For this purpose, a comparative analysis of time-use surveys will be used, analysing the time spent, and the time dedicated to household chores in Chile, Argentina, Uruguay and Spain. From an analytical viewpoint, the analysis will place social reproduction at the centre of the socio-economic system, showing that the economic crisis has affected women and men differently, and that in both Europe and Latin America the family pattern is being replaced by a dominant family model of a male provider and a double presence of women. The large-scale incorporation of women into the labour market has emphasised the role that women assume in the domestic sphere perpetuating gender segregation in employment and in domestic and care work
Basin-wide variation in tree hydraulic safety margins predicts the carbon balance of Amazon forests
Tropical forests face increasing climate risk1,2, yet our ability to predict their response to climate change is limited by poor understanding of their resistance to water stress. Although xylem embolism resistance thresholds (for example, Ψ50) and hydraulic safety margins (for example, HSM50) are important predictors of drought-induced mortality risk3–5, little is known about how these vary across Earth’s largest tropical forest. Here, we present a pan-Amazon, fully standardized hydraulic traits dataset and use it to assess regional variation in drought sensitivity and hydraulic trait ability to predict species distributions and long-term forest biomass accumulation. Parameters Ψ50 and HSM50 vary markedly across the Amazon and are related to average long-term rainfall characteristics. Both Ψ50 and HSM50 influence the biogeographical distribution of Amazon tree species. However, HSM50 was the only significant predictor of observed decadal-scale changes in forest biomass. Old-growth forests with wide HSM50 are gaining more biomass than are low HSM50 forests. We propose that this may be associated with a growth–mortality trade-off whereby trees in forests consisting of fast-growing species take greater hydraulic risks and face greater mortality risk. Moreover, in regions of more pronounced climatic change, we find evidence that forests are losing biomass, suggesting that species in these regions may be operating beyond their hydraulic limits. Continued climate change is likely to further reduce HSM50 in the Amazon6,7, with strong implications for the Amazon carbon sink
Anales de Edafología y Agrobiología Tomo 47 Número 3-4
Suelos. Física. Resistencia del suelo y susceptibilidad a la compactación en terrenos a monte sometidos a pastoreo. Por R. Pérez Moreira y F. Diaz-Fierros Viqueira.-- La reserva de agua útil de los suelos de Galicia. l. Relación con la textura y el contenido de materia orgánica. Por A. M. Martinez Cortizas.-- Química Empleo de aminas alifáticas en el estudio de asociaciones haloisita-esmectita en suelos. Por F. J. Aragoneses, J. Casas, y J. L. Martin de Vidales.-- Quelación por EDDHA de micronutrientes en suelos calizos. Ecuación de límite máximo. Por M. Juárez, J. Sánchez-Andréu, L. Pla y J. Jorda.-- Quelación por EDDHA de micronutrientes en suelos calizos. Ecuación de orden "n ".Por J. Sánchez-Andréu, M. Juarez, L. Pla y J. Jordá.-- Génesis, Clasificación y Cartografía Caracterización de un podsol ferro - húmico en el Puerto de la Quesera (Sierra del Ayllón). Por R. Espejo Serrano, F. Guerrero López y A. Saa Requejo.-- Natrixerales en el Baix Segre (Lleida). Por J. Bech i Borrás, J. Garrigo i Reixach y J. R. Torrento i Marselles.-- Aspectos micromorfológicos del horizonte superior en suelos artificiales (Sorribas) de las Islas Canarias. Por A. Rodríguez Rodríguez y J. M. Ontañón Sánchez.-- Fertilidad Influencia de diferentes factores del suelo sobre su contenido en microelementos asimilables: Mn, Fe, Cu y Zn. Por B. C. Ortega, Ma C. Ortega y J. G. de las Heras.--Incidencia de la salinidad del agua de riego en la mineralización del nitrógeno orgánico en suelos calizos del sureste español. Por J. García-Serna, J. Sánchez Andréu, M. Juárez y J. Mataix.-- Biología Vegetal-Fisiología Efectos de la toxicidad del flúor sobre el ciclo biológico en especies herbáceas dicotiledoneas. Por M. Ibarra, F. López Belmonte y Ma A. Diez.-- Efectos de la toxicidad del flúor sobre el ciclo biológico de especies de monocotiledoneas. Por M. Ibarra, F. López-Belmonte y Mª A . Diez.-- Proteasas ácidas en uvas Vitis vinifera (variedad Macabeo). l. Actividad proteásica durante su maduración. Por J. Marín Expósito, C. Miguel Gordillo, J. l. Maynar Mariño y J. L. Mesias Iglesias.-- Agro biología Efectos de enmiendas calcáreas en suelos fijadores de fósforo. Por S. G. Ramos Hernández y N. Aguilera Herrera.-- III. Trabajo Recapitulativo. Una deriva hacia hemiparasftismo de los líquenes epifitos: Análisis fisiológico de las relaciones con sus fitoforos. Por C. VicentePeer reviewed2019-08.- CopyBook.- Libnova.- Biblioteca IC
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