71 research outputs found

    G-arylated hydrogen-bonded cyclic tetramer assemblies with remarkable thermodynamic and kinetic stability

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    The preparation and self-assembly of novel G-C dinucleoside monomers that are equipped with electron-poor aryl groups at the G-N2 amino group have been studied. Such monomers associate via Watson-Crick H-bonding into discrete unstrained tetrameric macrocycles that arise as a thermodynamically and kinetically stabilized product in a wide variety of experimental conditions, including very polar solvent environments and low concentrations. G-arylation produces an increased stability of the cyclic assembly, as a result of a subtle interplay between enthalpic and entropic effects involving the solvent coordination sphereFunding from the European Research Council (ERC-StG 279548) and MINECO (CTQ2011-23659) is gratefully acknowledge

    2013. Documento Sevilla de Consenso sobre Alternativas a la Transfusión de Sangre Alogénica. Actualización del Documento Sevilla

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    La transfusión de sangre alogénica (TSA) no es inocua, y como consecuencia han surgido múltiples alternativas a la misma (ATSA). Existe variabilidad respecto a las indicaciones y buen uso de las ATSA. Dependiendo de la especialidad de los médicos que tratan a los pacientes, el grado de anemia, la política transfusional, la disponibilidad de las ATSA y el criterio personal, estas se usan de forma variable. Puesto que las ATSA tampoco son inocuas y pueden no cumplir criterios de coste-efectividad, la variabilidad en su uso es inaceptable. Las sociedades españolas de Anestesiología y Reanimación (SEDAR), Hematología y Hemoterapia (SEHH), Farmacia Hospitalaria (SEFH), Medicina Intensiva y Unidades Coronarias (SEMICYUC), Trombosis y Hemostasia (SETH) y Transfusiones Sanguíneas (SETS) han elaborado un documento de consenso para el buen uso de la ATSA. Un panel de expertos de las 6 sociedades ha llevado a cabo una revisión sistemática de la literatura médica y elaborado el 2013. Documento Sevilla de Consenso sobre Alternativas a la Transfusión de Sangre Alogénica. Solo se contempla las ATSA dirigidas a disminuir la transfusión de concentrado de hematíes. Se definen las ATSA como toda medida farmacológica y no farmacológica encaminada a disminuir la transfusión de concentrado de hematíes, preservando siempre la seguridad del paciente. La cuestión principal que se plantea en cada ítem se formula, en forma positiva o negativa, como: «La ATSA en cuestión reduce/no reduce la tasa transfusional». Para formular el grado de recomendación se ha usado la metodología Grades of Recommendation Assessment, Development and Evaluation (GRADE)

    Getting it right takes time: latency and performance in secondary school students

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    The relation between response time and performance in cog-nitive tasks is increasingly evident. In the present study, we analyzed the effect of participants’ spontaneous speed when responding to a mental rotation task. We carried out a data reanalysis from a previous study where a training of 3 practice sessions of 100 trials each was applied. The procedure was applied to a sample of 21 high school students (11 boys, 10 girls). The relation between response time and performance (hits) across the training trials was analyzed. In addition, we carried out a regression analysis of performance on the learn-ing task as a function of response time on that same task, as well as with the score on two previously applied tests of spa-tial intelligence and fluid intelligence. Results showed, (a) a significant relationship (r¼0.624) between response time and hits, (b) that the group of participants with longer response times performed better; (c) that participants’ response time explained most of the variance of their score on the training task in the regression analysis, although spatial and fluid intel-ligence scores improved the prediction of performance. Our results suggest that the reflective style achieves greater per-formance in solving spatial tasks, which could have important practical implications to promote a slower and more reflective style when solving school tasks with spatial componentsMinistry of Science, Innovation and Universities (PID2021-125677OB-I00

    Improving EEG-Based Motor Imagery Classification for Real-Time Applications Using the QSA Method

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    We present an improvement to the quaternion-based signal analysis (QSA) technique to extract electroencephalography (EEG) signal features with a view to developing real-time applications, particularly in motor imagery (IM) cognitive processes. The proposed methodology (iQSA, improved QSA) extracts features such as the average, variance, homogeneity, and contrast of EEG signals related to motor imagery in a more efficient manner (i.e., by reducing the number of samples needed to classify the signal and improving the classification percentage) compared to the original QSA technique. Specifically, we can sample the signal in variable time periods (from 0.5 s to 3 s, in half-a-second intervals) to determine the relationship between the number of samples and their effectiveness in classifying signals. In addition, to strengthen the classification process a number of boosting-technique-based decision trees were implemented. The results show an 82.30% accuracy rate for 0.5 s samples and 73.16% for 3 s samples. This is a significant improvement compared to the original QSA technique that offered results from 33.31% to 40.82% without sampling window and from 33.44% to 41.07% with sampling window, respectively. We can thus conclude that iQSA is better suited to develop real-time applications

    A genome-wide association study for survival from a multi-centre European study identified variants associated with COVID-19 risk of death

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    The clinical manifestations of SARS-CoV-2 infection vary widely among patients, from asymptomatic to life-threatening. Host genetics is one of the factors that contributes to this variability as previously reported by the COVID-19 Host Genetics Initiative (HGI), which identified sixteen loci associated with COVID-19 severity. Herein, we investigated the genetic determinants of COVID-19 mortality, by performing a case-only genome-wide survival analysis, 60 days after infection, of 3904 COVID-19 patients from the GEN-COVID and other European series (EGAS00001005304 study of the COVID-19 HGI). Using imputed genotype data, we carried out a survival analysis using the Cox model adjusted for age, age2, sex, series, time of infection, and the first ten principal components. We observed a genome-wide significant (P-value < 5.0 × 10−8) association of the rs117011822 variant, on chromosome 11, of rs7208524 on chromosome 17, approaching the genome-wide threshold (P-value = 5.19 × 10−8). A total of 113 variants were associated with survival at P-value < 1.0 × 10−5 and most of them regulated the expression of genes involved in immune response (e.g., CD300 and KLR genes), or in lung repair and function (e.g., FGF19 and CDH13). Overall, our results suggest that germline variants may modulate COVID-19 risk of death, possibly through the regulation of gene expression in immune response and lung function pathways

    Dust environment and dynamical history of a sample of short-period comets: II. 81P/Wild 2 and 103P/Hartley 2

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    Aims. This paper is a continuation of the first paper in this series, where we presented an extended study of the dust environment of a sample of short-period comets and their dynamical history. On this occasion, we focus on comets 81P/Wild 2 and 103P/Hartley 2, which are of special interest as targets of the spacecraft missions Stardust and EPOXI. Methods. As in the previous study, we used two sets of observational data: a set of images, acquired at Sierra Nevada and Lulin observatories, and the Afρ data as a function of the heliocentric distance provided by the amateur astronomical association Cometas-Obs. The dust environment of comets (dust loss rate, ejection velocities, and size distribution of the particles) was derived from our Monte Carlo dust tail code. To determine their dynamical history we used the numerical integrator Mercury 6.2 to ascertain the time spent by these objects in the Jupiter family Comet region. Results. From the dust analysis, we conclude that both 81P/Wild 2 and 103P/Hartley 2 are dusty comets, with an annual dust production rate of 2.8 × 109 kg yr-1 and (0.4-1.5) × 109 kg yr-1, respectively. From the dynamical analysis, we determined their time spent in the Jupiter family Comet region as ~40 yr in the case of 81P/Wild 2 and ~1000 yr for comet 103P/Hartley 2. These results imply that 81P/Wild 2 is the youngest and the most active comet of the eleven short-period comets studied so far, which tends to favor the correlation between the time spent in JFCs region and the comet activity previously discussed

    Anti-tumour necrosis factor discontinuation in inflammatory bowel disease patients in remission: study protocol of a prospective, multicentre, randomized clinical trial

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    Background: Patients with inflammatory bowel disease who achieve remission with anti-tumour necrosis factor (anti-TNF) drugs may have treatment withdrawn due to safety concerns and cost considerations, but there is a lack of prospective, controlled data investigating this strategy. The primary study aim is to compare the rates of clinical remission at 1?year in patients who discontinue anti-TNF treatment versus those who continue treatment. Methods: This is an ongoing, prospective, double-blind, multicentre, randomized, placebo-controlled study in patients with Crohn?s disease or ulcerative colitis who have achieved clinical remission for ?6?months with an anti-TNF treatment and an immunosuppressant. Patients are being randomized 1:1 to discontinue anti-TNF therapy or continue therapy. Randomization stratifies patients by the type of inflammatory bowel disease and drug (infliximab versus adalimumab) at study inclusion. The primary endpoint of the study is sustained clinical remission at 1?year. Other endpoints include endoscopic and radiological activity, patient-reported outcomes (quality of life, work productivity), safety and predictive factors for relapse. The required sample size is 194 patients. In addition to the main analysis (discontinuation versus continuation), subanalyses will include stratification by type of inflammatory bowel disease, phenotype and previous treatment. Biological samples will be obtained to identify factors predictive of relapse after treatment withdrawal. Results: Enrolment began in 2016, and the study is expected to end in 2020. Conclusions: This study will contribute prospective, controlled data on outcomes and predictors of relapse in patients with inflammatory bowel disease after withdrawal of anti-TNF agents following achievement of clinical remission. Clinical trial reference number: EudraCT 2015-001410-1

    Euclid: I. Overview of the Euclid mission

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    The current standard model of cosmology successfully describes a variety of measurements, but the nature of its main ingredients,dark matter and dark energy, remains unknown. Euclid is a medium-class mission in the Cosmic Vision 2015–2025 programme of theEuropean Space Agency (ESA) that will provide high-resolution optical imaging, as well as near-infrared imaging and spectroscopy,over about 14 000 deg² of extragalactic sky. In addition to accurate weak lensing and clustering measurements that probe structureformation over half of the age of the Universe, its primary probes for cosmology, these exquisite data will enable a wide range ofscience. This paper provides a high-level overview of the mission, summarising the survey characteristics, the various data-processingsteps, and data products. We also highlight the main science objectives and expected performance

    Software and computing for Run 3 of the ATLAS experiment at the LHC

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    The ATLAS experiment has developed extensive software and distributed computing systems for Run 3 of the LHC. These systems are described in detail, including software infrastructure and workflows, distributed data and workload management, database infrastructure, and validation. The use of these systems to prepare the data for physics analysis and assess its quality are described, along with the software tools used for data analysis itself. An outlook for the development of these projects towards Run 4 is also provided
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