62 research outputs found

    Mineralogical and isotopic characterization of graphite deposits from the Anatectic Complex of Toledo, central Spain

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    Graphite is found dispersed in high-grade metapelitic rocks of the Anatectic Complex of Toledo (ACT) and was mined during the mid twentieth century in places where it has been concentrated (Guadamur and la Puebla de Montalbán mines). Some samples from these mines show variable but significant alteration intensity, reaching very low-T hydrothermal (supergene) conditions for some samples from the waste heap of the Guadamur site (<100 °C and 1 kbar). Micro-Raman and XRD data indicate that all the studied ACT graphite is of high crystallinity irrespective of the degree of hydrothermal alteration. Chemical differences were obtained for graphite δ13C composition. ACT granulitic graphite shows δ13CPDB values in the range of −20.5 to −27.8 ‰, indicating a biogenic origin. Interaction of graphite with hydrothermal fluids does not modify isotopic compositions even in the most transformed samples from mining sites. The different isotopic signatures of graphite from the mining sites reflect its contrasted primary carbon source. The high crystallinity of studied graphite makes this area of central Spain suitable for graphitic exploration and its potential exploitation, due to the low carbon content required for its viability and its strategic applications in advanced technologies, such as graphene synthesis.This work is included in the objectives of, and supported by, the CGL2012-32822 project of the Ministerio de Economía y Competitividad of Spain and the 910492-UCM group.Peer reviewe

    Gestión de personas para propiciar la felicidad laboral, en la empresa “Arenera Jaén” de Piura, Perú

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    El presente estudio tuvo como objetivo general determinar cómo la gestión de personas puede propiciar la felicidad laboral en la empresa “Arenera Jaén” de la ciudad de Piura, en el año 2019. Las teorías en que se basó fueron: La Teoría de Sonja Lyubomirsky, la Teoría de la auténtica felicidad, de Seligman, y la Teoría de la ciencia de la felicidad. Es de tipo no experimental, de enfoque mixto, cuantitativo y cualitativo; su diseño es descriptivo-explicativo para la investigación cuantitativa, y diseño fenomenológico para la investigación cualitativa. Asimismo, la muestra fue de 21 colaboradores, 01 jefe, 08 asistentes y 12 administrativos. Las técnicas usadas en esta investigación fueron: la Entrevista, por medio de la Guía Temática; y la Encuesta, a través de Cuestionario. La validez de los instrumentos fue determinada por juicio de tres expertos; y, la confiabilidad mediante el estadístico Alfa de Cronbach. Concluyéndose que, el 45% de colaboradores se sienten totalmente felices de trabajar en la empresa; además, el jefe considera que incentiva la felicidad de sus colaboradores buscando un equilibrio entre el trabajo y la familia. Aun así, solo el 40% de los colaboradores está totalmente de acuerdo que la felicidad es la aspiración máxima de las personas

    Mineralogical and isotopic characterization of graphite 2 deposits from the Anatectic Complex of Toledo, central Spain

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    Graphite is found dispersed in high-grade metapelitic rocks of the Anatectic Complex of Toledo 15 (ACT) and was mined during the mid twentieth century in places where it has been concentrated 16 (Guadamur and la Puebla de Montalbán mines). Some samples from these mines show variable but 17 significant alteration intensity, reaching very low-T hydrothermal (supergene) conditions for some 18 samples from the waste heap of the Guadamur site (<100 ºC and 1kbar). Micro-Raman and XRD data 19 indicate that all the studied ACT graphite is of high crystallinity irrespectively of the degree of hydrothermal alteration. Chemical differences were obtained for graphite δ 13 20 C composition. ACT granulitic graphite shows δ 13 21 CPDB values in the range of -20.5 to -27.8‰, indicating a biogenic origin. 22 Interaction of graphite with hydrothermal fluids does not modify isotopic compositions even in the 23 most transformed samples from mining sites. The different isotopic signatures of graphite from the 24 mining sites reflect its contrasted primary carbon source. The high crystallinity of studied graphite 25 makes this area of central Spain suitable for graphitic exploration and its potential exploitation, due to 26 the low carbon content required for its viability and its strategic applications in advanced technologies, 27 such as graphene synthesis

    Arsenic and chromium topsoil levels and cancer mortality in Spain

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    Spatio-temporal cancer mortality studies in Spain have revealed patterns for some tumours which display a distribution that is similar across the sexes and persists over time. Such characteristics would be common to tumours that shared risk factors, including the chemical soil composition. The objective of the present study is to assess the association between levels of chromium and arsenic in soil and the cancer mortality. This is an ecological cancer mortality study at municipal level, covering 861,440 cancer deaths in 7917 Spanish mainland towns from 1999 to 2008. Chromium and arsenic topsoil levels (partial extraction) were determined by ICP-MS at 13,317 sampling points. To estimate the effect of these concentrations on mortality, we fitted Besag, York and Mollié models, which included, as explanatory variables, each town’s chromium and arsenic soil levels, estimated by kriging. In addition, we also fitted geostatistical-spatial models including sample locations and town centroids (non-aligned data), using the integrated nested Laplace approximation (INLA) and stochastic partial differential equations (SPDE). All results were adjusted for socio-demographic variables and proximity to industrial emissions. The results showed a statistical association in men and women alike, between arsenic soil levels and mortality due to cancers of the stomach, pancreas, lung and brain and non-Hodgkin’s lymphomas (NHL). Among men, an association was observed with cancers of the prostate, buccal cavity and pharynx, oesophagus, colorectal and kidney. Chromium topsoil levels were associated with mortality among women alone, in cancers of the upper gastrointestinal tract, breast and NHL. Our results suggest that chronic exposure arising from low levels of arsenic and chromium in topsoil could be a potential risk factor for developing cancer. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s11356-016-6806-y) contains supplementary material, which is available to authorized users

    A 3D Peptide/[60]Fullerene Hybrid for Multivalent Recognition

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    Multivalent ligand presentation is a powerful strategy for the development of specific binders and inhibitors. Peptide/[60]fullerene hybrids have now been synthesized that exploit the complete substitution of the fullerene scaffold to afford globular structures presenting twelve copies of a peptide ligand for the recognition of E-selectin. Fully substituted peptide/[60]fullerene hexakis-adducts offer an excellent opportunity for multivalent protein recognition. In contrast to monofunctionalized fullerene hybrids, peptide/[60]fullerene hexakis-adducts display multiple copies of a peptide in close spatial proximity and in the three dimensions of space. High affinity peptide binders for almost any target can be currently identified by in vitro evolution techniques, often providing synthetically simpler alternatives to natural ligands. However, despite the potential of peptide/[60]fullerene hexakis-adducts, these promising conjugates have not been reported to date. Here we present a synthetic strategy for the construction of 3D multivalent hybrids that are able to bind with high affinity the E-selectin. The here synthesized fully substituted peptide/[60]fullerene hybrids and their multivalent recognition of natural receptors constitute a proof of principle for their future application as functional biocompatible materialsThis work was partially supported by the Spanish Agencia Estatal de Investigación (AEI) [SAF2017-89890-R, PCI2019-103400, PID2020-117143RB-I00, PID2020-114653RB-I00 and PID2020-115120GB-I00], Xunta de Galicia (ED431C 2017/25 and Centro singular de investigación de Galicia accreditation 2019–2022, ED431G 2019/03) and the European Commission (EC) (European Regional Development Fund-ERDF). J.M. thanks the ERC-STG (DYNAP, 677786), ERC-POC (TraffikGene, 838002), Xunta de Galicia (Oportunius Program) and Human Frontier Science Programme Young Investigator Grant (RGY0066/2017) for funding. J.J.R. received a Beatriz Galindo Grant (BEAGAL18-00051) by the Spanish Ministerio de Universidades. I.G. received predoctoral fellowships (ED481A-2018/116 and FPU17/00941). J.C.-G. thanks the Comunidad de Madrid Atracción de Talento program (2018-T2/BMD-10275)S

    Cirugía mínimamente invasiva de estrabismo modificada

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    Introducción: La cirugía mínimamente invasiva de estrabismo ha revolucionado el concepto de la cirugía tradicional de estrabismo. Este procedimiento se realiza con mínima disrupción anatómica entre el músculo y el tejido perimuscular. Objetivo: Describir una propuesta de modificación a la técnica de cirugía mínimamente invasiva de estrabismo. Métodos: Se revisó la literatura en español e inglés, sin restricciones de fecha, para investigar modificaciones reportadas a la técnica de cirugía mínimamente invasiva de estrabismo. En las modificaciones revisadas, coexiste la posibilidad de que ocurra la complicación de músculo deslizado o músculo perdido. Para realizar una técnica quirúrgica segura se identificaron los aspectos que pueden influir en esta, que son el agarre muscular y su fijación escleral, sin ampliar las microincisiones. Resultados: En la técnica modificada se emplearon pinzas curvas de Moody-Castroviejo, para ampliar el campo operatorio. Se utilizó una sola sutura no reabsorbible de ácido poliglicólico para el agarre muscular; se pasa primero por el espesor muscular y después por los extremos superior e inferior de la inserción muscular, lo cual ofrece seguridad al procedimiento. Se propone el uso del Dardenne, instrumento oftalmológico utilizado en la realización de pupiloplastias, para traer el extremo opuesto de la sutura y realizar un nudo de Siepser; al cortar la sutura, quedan los cabos por debajo del túnel conjuntival, sin ampliar las microincisiones. Conclusiones: Las modificaciones a la técnica de cirugía mínimamente invasiva de estrabismo, que propone este trabajo, permiten mejor agarre y fijación del músculo

    Cadmium (Cd) and Lead (Pb) topsoil levels and incidence of childhood leukemias

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    There are few well-established risk factors for childhood leukemias. While the frequency of childhood leukemias might be partially attributable to some diseases (accounting for a small fraction of cases) or ionizing radiation, the role of heavy metals has not been assessed. The objective of our study was to assess the potential association between levels of cadmium (Cd) and lead (PB) in soil and childhood leukemias incidence. We conducted a population-based case-control study of childhood leukaemia in Spain, covering 2897 incident cases gathered from the Spanish Registry of Childhood Tumours and including 14 Spanish Regions with a total population of 5,307,433 children (period 1996-2015). Cd and Pb bioavailable levels at every children's home address were estimated using data from the Geochemical Atlas of Spain. We used logistic regression to estimate odds ratios (ORs) and their 95% confidence intervals (95%CIs); we included as covariates: sex, rurality, employment rate and socioeconomic status. Metal levels were analysed according to two definitions: as continuous variable assuming linearity and as categorical variables to explore a potentially nonlinear association (quantiles). Increases in both Cd and Pb topsoil levels were associated with increased probability of childhood leukemias incidence. The results for the models with the continuous variables showed that a unit increase on the topsoil level was associated with an OR of 1.11 for Cd (95%CI 1.00-1.24) and an OR of 1.10 for Pb (95%CI 0.99-1.21). Our study may point towards a possible link between residential Cd and Pb topsoil levels and the probability of childhood leukemias incidence. Residing in a location with the highest concentrations of these heavy metals compared to those locations with the lowest could increase the risk around a 20%, for both Cd and Pb.This work was supported by Carlos III Health Institute: FIS 12/01416, AESI PI16CIII/00009, AESI PI19CIII/00025.S

    The Importance of Spanish Data (BDMIN & PANORAMA MINERO) in the European Raw Materials Knowledge Base (EURMKB)

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    [EN] The IGME has an extensive experience in the field of mineral resources and the main source of information is the Mineral Resources Database (BDMIN) that integrates the geological‐mining information on occurrences, mines and exploitations (active and inactive) of metallic, nonmetallic and industrial minerals, and rocks in Spain. In addition, since 1981, the Panorama Minero has been carried out with the aim of providing reliable data on Spanish mining production, based on the Spanish Mining Statistics (MITERD). This information includes data on the national production of minerals, in tonnage and value, metallurgical production, foreign trade, etc. Other sources include the National Mining Cadastre and Foreign Trade statistics from the Tax Agency.Peer reviewe

    Strategic raw materials for the energy and digital transition in Spain

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    [EN] One of the main concerns of the European Commission is critical raw materials (CRM), necessary for daily life in a wide range of goods and applications. The EU's industry and economy depend on international markets for many important raw materials, which are produced and supplied by third countries. These CRMs are closely linked to clean technologies, technological progress and quality of life. Concern about access to CRMs led the European Commission to draw up a first list of critical raw materials (CRM) in 2011, and to schedule its review and update every three years, the last being in 2020.Peer reviewe

    Adaptation to Change Questionnaire for Nurses: Validation and New Needs in the Context of COVID-19

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    Background: The worldwide pandemic caused by the SARS-CoV-2 coronavirus has challenged healthcare systems and the professionals who work in them. This challenge involves strong changes to which nurses have had to quickly adapt. Emotional and cognitive–behavioral factors influence the capacity for adaptation to change. Based on this model, the objective of this study was to validate the Adaptation to Change Questionnaire (ADAPTA-10) for identifying professionals in a population of nurses who have problems adapting to adverse situations such as those caused by COVID-19. Methods: This study was performed with a sample of 351 nurses. (3) Results: The ADAPTA-10 questionnaire was found to have good psychometric properties, and to be an effective, useful tool for nurses in research and clinical practice. The two-dimensional structure proposed in the original model was confirmed. Scales are also provided by sex for evaluation of adaptation to change; the highest scores on the emotional component were among nurses who had not personally encountered the virus. Conclusions: This instrument will be able to detect of the needs for adaptation to the new reality associated with COVID-19, as well as other situations in which nurses are immersed that demand adaptation strategies
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