Hormigón de altas prestaciones basado en aglomerantes poliméricos

This paper studies the performance of concrete whose chief components are natural aggregate and an organic binder —a thermosetting polyester resin— denominated polymer concrete or PC. The material was examined macro- and microscopically and its basic physical and mechanical properties were determined using mercury porosimetry, scanning electron microscopy (SEM-EDAX), X-ray diffraction (XRD) and strength tests (modulus of elasticity, stress-strain curves and ultimate strengths). According to the results of these experimental studies, the PC exhibited a low density (4.8%), closed pore system and a concomitantly continuous internal microstructure. This would at least partially explain its mechanical out-performance of traditional concrete, with average compressive and flexural strength values of 100 MPa and over 20 MPa, respectively. In the absence of standard criteria, the bending test was found to be a useful supplement to compressive strength tests for establishing PC strength classes.Este trabajo de investigación aborda el estudio de un hormigón de altas prestaciones, formado por áridos naturales y un aglomerante orgánico constituido por una resina termoestable poliéster, denominado hormigón polimérico HP. Se describe el material a nivel microscópico y macroscópico, presentando sus propiedades físicas y mecánicas fundamentales, mediante diferentes técnicas experimentales, tales como: porosimetría de mercurio, microscopía electrónica (SEM-EDAX), difracción de rayos X (DRX) y ensayos mecánicos (módulo de elasticidad, curvas tensión- deformación y resistencias últimas). Como consecuencia del estudio experimental llevado a cabo, se ha podido apreciar cómo el HP está formado por porosidad cerrada del 4,8%, proporcionando una elevada continuidad a su microestructura interna, lo que justifica, en parte, la mejora de propiedades mecánicas respecto al hormigón tradicional, con unos valores medios de resistencia a compresión de 100 MPa y superiores a 20 MPa en su resistencia a flexotracción. Debido a la falta de estandarización, se ha concluido cómo el ensayo de flexión puede ser un procedimiento adicional al de compresión, a la hora de establecer las clases resistentes del HP

Effect of Ph and vegetation cover in soil organic matter structure at a high-mountain ecosystem (Sierra Nevada National Park, Granada, Spain)

Poster nº 8246 en EGU General Assembly 2020, Online, 4–8 May 2020During the last decade, soil organic matter dynamics and its determining factors have received increased attention, mainly due to the evident implication of these parameters in climate change understanding, predictions and possible management. High-mountain soil could be considered as hotspot of climate change dynamic since its high carbon accumulation and low organic matter degradation rates could be seriously altered by slight changes in temperature and rainfall regimes associated to climate change effects. In the particular case of Sierra Nevada National Park, this threat could be even stronger due to its Southern character, although its elevated biodiversity could shed some light on how could we predict and manage climate change in the future. In this study, a quantitative and qualitative organic matter characterization was performed and soil microbial activity measured to evaluate the implication of pH and vegetation in soil organic matter dynamics. The sampling areas were selected according to vegetation and soil pH; with distinct soil pH (area A with pH7) and vegetation (high-mountain shrubs and pine reforested area). Soil samples were collected under the influence of several plant species representatives of each vegetation series. Six samples were finally obtained (five replicates each); three were collected in area A under Juniperus communis ssp. Nana (ENE), Genista versicolor (PIO) and Pinus sylvestris (PSI) and other three were collected in area B under Juniperus Sabina (SAB), Astragalus nevadensis (AST) and Pinus sylvestris (PCA). Qualitative and quantitative analyses of soil organic matter were made to establish a possible relationship with microbial activity estimated by respiration rate (alkali trap) and fungi-to-bacteria ratio using a plate count method. Soil easily oxidizable organic carbon content was determined by the Walkley-Black method (SOC %) and organic matter amount was estimated by weight loss on ignition (LOI %). Analytical pyrolysis (Py-GC/MS) was used to analyse in detail the soil organic carbon composition. Our results showed that the microbial and therefore the dynamics of organic matter is influenced by both, soil pH and soil of organic matter. So that the pH in acidic media prevail as a determining factor of microbial growth over soil organic matter composition conditioned by vegetation.Ministerio de Ciencia Innovación y Universidades (MICIU) for INTERCARBON project (CGL2016-78937-R). N.T. Jiménez-Morillo and L. San Emeterio also thanks MICIU for funding FPI research grants (BES-2013-062573 and Ref. BES-2017-07968). Mrs Desiré Monis is acknowledged for technical assistance

Carácterización y transformación de un residuo industrial (lodo de papel estucado) en un material con propiedades puzolánicas

The effective re-use of industrial by-products calls for an understanding of their chemical, mineralogical and physical characteristics. The by-product used in this study was coated paper industry sludge from a plant whose sole prime material is recycled paper. Due to its high organic and calcium carbonate content and the presence of several clayey materials such as talc and kaolinite, incineration conditions had a significant effect on the mineralogy of such sludge. The present study examined the impact of such conditions on the pozzolanic properties of coated paper sludge. Several temperature intervals ranging from 600 to 750 ºC were studied to determine the conditions yielding the most promising pozzolanic properties.La necesidad de dar un correcto uso a los subproductos industriales requiere del conocimiento de sus características, tanto desde un punto de vista químico como mineralógico y físico. El subproducto utilizado para esta investigación es un lodo de papel estucado procedente de la industria papelera, la cual usa como materias primas un 100% de material reciclado. Debido al alto contenido de materia orgánica y carbonato cálcico y a la presencia de diferentes materiales arcillosos, como el talco y la caolinita, las condiciones de calcinación presentan un papel principal en la mineralogía de este lodo. En el actual trabajo se considera el papel que juegan estas condiciones, tiempo y permanencia en horno, en las propiedades puzolánicas del lodo de papel estucado como material cementante. Por esta razón, se estudiaron diferentes intervalos de temperatura, entre 600 y 750 ºC y 2 horas de permanencia en horno con el objetivo de obtener las mejores propiedades puzolánicas

COST ES0602: towards a European network on chemical weather forecasting and information systems

The COST ES0602 action provides a forum for benchmarking approaches and practices in data exchange and multi-model capabilities for chemical weather forecasting and near real-time information services in Europe. The action includes approximately 30 participants from 19 countries, and its duration is from 2007 to 2011 (<a href="http://www.chemicalweather.eu/" target="_blank">http://www.chemicalweather.eu/</a>). Major efforts have been dedicated in other actions and projects to the development of infrastructures for data flow. We have therefore aimed for collaboration with ongoing actions towards developing near real-time exchange of input data for air quality forecasting. We have collected information on the operational air quality forecasting models on a regional and continental scale in a structured form, and inter-compared and evaluated the physical and chemical structure of these models. We have also constructed a European chemical weather forecasting portal that includes links to most of the available chemical weather forecasting systems in Europe. The collaboration also includes the examination of the case studies that have been organized within COST-728, in order to inter-compare and evaluate the models against experimental data. We have also constructed an operational model forecasting ensemble. Data from a representative set of regional background stations have been selected, and the operational forecasts for this set of sites will be inter-compared and evaluated. The Action has investigated, analysed and reviewed existing chemical weather information systems and services, and will provide recommendations on best practices concerning the presentation and dissemination of chemical weather information towards the public and decision makers

Preservation of Quercus robur germplasm by cryostorage of embryogenic cultures derived from mature trees and rapd analysis of genetic stability

This study reports on the cryostorage of embryogenic lines derived from selected mature Quercus robur trees, following application of the PVS2-vitrification based procedure. In seven oak genotypes, embryo recovery levels ranging from 57-92% were obtained when 4-6 mg embryo clumps were precultured for 3 days on 0.3 M sucrose basal medium, treated with PVS2 solution for 60 min at 24ºC, and then immersed in liquid nitrogen (LN). Embryos of six out of seven lines were cryostored for one week and one year and used to evaluate cryopreservation tolerance, germination ability and to assess genetic fidelity by random amplified polymorphic DNA (RAPD) markers. There were no significant differences between the recovery frequencies of samples retrieved from LN after 1 week and 1 year of cryostorage. In five out of six lines, RAPD profiles of cryopreserved somatic embryos and regenerated plantlets were identical to those of the controls. Although polymorphisms were detected in only one cryostored embryo of one genotype, no genetic instability was found in the regenerated plantlets. This methodology appears to be suitable for long-term storage of this valuable germplasm, as the recovered plantlets were found to be genetically stable.Xunta de Galicia project: PGIDIT03RFO40001PR MEC (Spain) project: AGL2006-01387/FORPeer reviewe

Intermediate window observable for the hadronic vacuum polarization contribution to the muon g−2g-2 from O(a)(a) improved Wilson quarks

Following the publication of the new measurement of the anomalous magnetic moment of the muon, the discrepancy between experiment and the theory prediction from the g−2 theory initiative has increased to 4.2σ. Recent lattice QCD calculations predict values for the hadronic vacuum polarization contribution that are larger than the data-driven estimates, bringing the Standard Model prediction closer to the experimental measurement. Euclidean time windows in the time-momentum representation of the hadronic vacuum polarization contribution to the muon g−2 can help clarify the discrepancy between the phenomenological and lattice predictions. We present our calculation of the intermediate distance window contribution using Nf=2+1 flavors of O(a) improved Wilson quarks. We employ ensembles at six lattice spacings below 0.1fm and pion masses down to the physical value. We present a detailed study of the continuum limit, using two discretizations of the vector current and two independent sets of improvement coefficients. Our result at the physical point displays a tension of 3.9σ with a recent evaluation of the intermediate window based on the data-driven method

Feasibility study of the National Autistic Society EarlyBird parent support programme

The EarlyBird programme is a group-based psychoeducation intervention for parents of young children with autism. Although it is widely used in the United Kingdom, the evidence base for the programme is very limited. Using a mixed method, non-randomised research design, we aimed to test (1) the acceptability of the research procedures (recruitment, retention, suitability of measures), (2) the parental acceptability of EarlyBird (attendance, views of the programme, perceived changes) and (3) the facilitator acceptability of EarlyBird (fidelity, views of the programme, perceived changes). Seventeen families with a 2- to 5-year-old autistic child and 10 EarlyBird facilitators took part. Pre- and post-intervention assessment included measures of the child’s autism characteristics, cognitive ability, adaptive behaviour, emotional and behavioural problems and parent-reported autism knowledge, parenting competence, stress and wellbeing. Semi-structured interviews were completed at post-intervention with parents and facilitators. For those involved in the study, the research procedures were generally acceptable, retention rates were high and the research protocol was administered as planned. Generally, positive views of the intervention were expressed by parents and facilitators. Although the uncontrolled, within-participant design does not allow us to test for efficacy, change in several outcome measures from pre- to post-intervention was in the expected direction. Difficulties were encountered with recruitment (opt-in to the groups was ~56% and opt-in to the research was 63%), and strategies to enhance recruitment need to be built into any future trial. These findings should be used to inform protocols for pragmatic, controlled trials of EarlyBird and other group-based interventions for parents with young autistic children

Lenalidomide-dexamethasone versus observation in high-risk smoldering myeloma after 12 years of median follow-up time: A randomized, open-label study

[Background]: Smoldering multiple myeloma (SMM) is a heterogeneous disease in terms of progression to myeloma (MM), but its standard of care continues to be observation. [Methods]: The QuiRedex phase 3 trial initiated in 2007 included 119 high-risk patients with SMM randomized to treatment or observation. Treatment consisted of nine 4-week induction cycles (lenalidomide [Rd], 25 mg on days 1–21 plus dexamethasone, 20 mg on days 1–4 and 12–15), followed by maintenance (R, 10 mg on days 1–21) for up to 2 years. The primary end-point was time to progression (TTP) to myeloma based on per protocol population. Secondary end-points were overall survival (OS), response rate, and safety. An update of the trial after a long-term follow-up is presented here. This trial was registered with ClinicalTrials.gov (NCT00480363). [Findings]: After a median follow-up time of 12.5 years (range: 10.4–13.6), the median TTP to MM was 2.1 years in the observation arm and 9.5 years in the Rd arm (HR: 0.28, 95% CI: 0.18–0.44, p < 0.0001). The median OS was 8.5 years in the abstention arm and not reached in the Rd group (HR: 0.57, 95% CI: 0.34–0.95, p = 0.032). Patients who progressed received optimized treatments according to the standards of care, and the OS from progression was comparable in both arms (p = 0.96). [Interpretation]: This analysis confirms that early treatment with Rd for high-risk SMM translates into a sustained benefit in both TTP and OS.This study was also supported by the Cooperative Research Thematic Network grant RD12/0036/0058 and RD12/0036/0046 and Instituto de Salud Carlos III/Subdirección General de Investigación Sanitaria, Spain. (FIS:PI12/02311/01761/01569)

How teachers' practices and students' attitudes towards technology affect mathematics achievement: results and insights from PISA 2012

The present work seeks to deepen the impact of factors linked to the characteristics of teaching practices and students' attitudes towards the use of technology on their performance in mathematics in the process of teaching-learning in the Spanish context. In this sense, this study is a secondary analysis of the PISA 2012 data. Therefore, it is an ex post facto design. Regarding the attitudes and the contextual variables, the results do coincide with the accumulated evidence. However, once these contextual effects have been controlled for, the negative relationship found between the pedagogic strategies used by the teachers and the mathematics score cannot but convey perplexity, since the results relative to student-oriented, formative assessment and teacher-directed instruction are clearly contradictory to the solid previous evidence. The data do not allow us to explain this paradoxical result. We dare to point to a conjecture that we find plausible. All these complex variables are informed through questionnaires responded to by students and require a great degree of inference in the answers. Future studies must consider the complexity of the measured variables as well as the students' perception and understanding of them

Water in star-forming regions with Herschel (WISH). V. The physical conditions in low-mass protostellar outflows revealed by multi-transition water observations

International audienceContext: Outflows are an important part of the star formation process as both the result of ongoing active accretion and one of the main sources of mechanical feedback on small scales. Water is the ideal tracer of these effects because it is present in high abundance in various parts of the protostar. Method: We present \textit{Herschel} HIFI spectra of multiple water-transitions towards 29 nearby Class 0/I protostars as part of the WISH Survey. These are decomposed into different Gaussian components, with each related to one of three parts of the protostellar system; quiescent envelope, cavity shock and spot shocks in the jet and at the base of the outflow. We then constrain the excitation conditions present in the two outflow-related components. Results: Water emission is optically thick but effectively thin, with line ratios that do not vary with velocity, in contrast to CO. The physical conditions of the cavity and spot shocks are similar, with post-shock H$_{2}$ densities of order 10$^{5}-$10$^{8}$\,cm$^{-3}$ and H$_{2}$O column densities of order 10$^{16}-$10$^{18}$\,cm$^{-2}$. H$_{2}$O emission originates in compact emitting regions: for the spot shocks these correspond to point sources with radii of order 10-200\,AU, while for the cavity shocks these come from a thin layer along the outflow cavity wall with thickness of order 1-30\,AU. Conclusions: Water emission at the source position traces two distinct kinematic components in the outflow; J shocks at the base of the outflow or in the jet, and C shocks in a thin layer in the cavity wall. Class I sources have similar excitation conditions to Class 0 sources, but generally smaller line-widths and emitting region sizes. We suggest that it is the velocity of the wind driving the outflow, rather than the decrease in envelope density or mass, that is the cause of the decrease in H$_{2}$O intensity between Class 0 and I