44 research outputs found

    Functionalization of a Few-Layer Antimonene with Oligonucleotides for DNA Sensing

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    This document is the Accepted Manuscript version of a Published Work that appeared in final form in ACS Applied Nano Materials, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see: https://pubs.acs.org/doi/abs/10.1021/acsanm.0c00335Antimonene, a novel group 15 two-dimensional material, is functionalized with an oligonucleotide as a first step to DNA sensor development. The functionalization process leads to a few-layer antimonene modified with DNA that after deposition on gold screen-printed electrodes gives a simple and efficient DNA electrochemical sensing platform. We provide theoretical and experimental data of the DNA–antimonene interaction, confirming that oligonucleotides interact noncovalently but strongly with antimonene. The potential utility of this antimonene-based sensing device is assessed using, as a case of study, a sequence from the BRCA1 gene as the target DNA. The selectivity of the device allows not only recognition of a specific DNA sequence but also detection of a mutation in this gene associated with breast cancer, directly in clinical samplesThe Ministerio de Ciencia Innovación y Universidades (Grants CTQ2017-84309-C2-1-R, MAT2016-77608-C3-1-P, PCI2018-093081, JTC2017/2D-Sb&Ge, and FIS2016-80434-P), Generalitat Valenciana (Grant APOSTD/2017/010), and CAM (Grants TransNANOAVANSENS and 2017-T1/BIO-5435) are gratefully acknowledged. We also acknowledge the María de Maeztu Programme for Units of Excellence in R&D (MDM-2014-0377), the Fundación Ramón Areces, and the computer resources and assistance provided by the Centro de Computación Científica of the Universidad Autónoma de Madri

    Pobreza infantil y educación

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    Los autores del artículo analizan el impacto de la pobreza infantil en la educación y su relación con el fracaso y el abandono escolar. Proponen medidas urgentes y líneas de intervención para romper el círculo vicioso que vincula la pobreza a la exclusión escolar y social. Se trata de un fenómeno complejo que exige una respuesta sistémica y articulada por parte de las políticas educativas, de salud y sociales

    Pobreza infantil y educación

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    P. 74-79Los autores del artículo analizan el impacto de la pobreza infantil en la educación y su relación con el fracaso y el abandono escolar. Proponen medidas urgentes y líneas de intervención para romper el círculo vicioso que vincula la pobreza a la exclusión escolar y social. Se trata de un fenómeno complejo que exige una respuesta sistémica y articulada por parte de las políticas educativas, de salud y sociales.S

    Sensitivity of a tonne-scale NEXT detector for neutrinoless double beta decay searches

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    The Neutrino Experiment with a Xenon TPC (NEXT) searches for the neutrinoless double-beta decay of Xe-136 using high-pressure xenon gas TPCs with electroluminescent amplification. A scaled-up version of this technology with about 1 tonne of enriched xenon could reach in less than 5 years of operation a sensitivity to the half-life of neutrinoless double-beta decay decay better than 1E27 years, improving the current limits by at least one order of magnitude. This prediction is based on a well-understood background model dominated by radiogenic sources. The detector concept presented here represents a first step on a compelling path towards sensitivity to the parameter space defined by the inverted ordering of neutrino masses, and beyond.Comment: 22 pages, 11 figure

    Boosting background suppression in the NEXT experiment through Richardson-Lucy deconvolution

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    Next-generation neutrinoless double beta decay experiments aim for half-life sensitivities of ~102710^{27} yr, requiring suppressing backgrounds to <1 count/tonne/yr. For this, any extra background rejection handle, beyond excellent energy resolution and the use of extremely radiopure materials, is of utmost importance. The NEXT experiment exploits differences in the spatial ionization patterns of double beta decay and single-electron events to discriminate signal from background. While the former display two Bragg peak dense ionization regions at the opposite ends of the track, the latter typically have only one such feature. Thus, comparing the energies at the track extremes provides an additional rejection tool. The unique combination of the topology-based background discrimination and excellent energy resolution (1% FWHM at the Q-value of the decay) is the distinguishing feature of NEXT. Previous studies demonstrated a topological background rejection factor of ~5 when reconstructing electron-positron pairs in the 208^{208}Tl 1.6 MeV double escape peak (with Compton events as background), recorded in the NEXT-White demonstrator at the Laboratorio Subterr\'aneo de Canfranc, with 72% signal efficiency. This was recently improved through the use of a deep convolutional neural network to yield a background rejection factor of ~10 with 65% signal efficiency. Here, we present a new reconstruction method, based on the Richardson-Lucy deconvolution algorithm, which allows reversing the blurring induced by electron diffusion and electroluminescence light production in the NEXT TPC. The new method yields highly refined 3D images of reconstructed events, and, as a result, significantly improves the topological background discrimination. When applied to real-data 1.6 MeV ee+e^-e^+ pairs, it leads to a background rejection factor of 27 at 57% signal efficiency.Comment: Submitted to JHE

    Sensitivity of a tonne-scale NEXT detector for neutrinoless double-beta decay searches

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    The Neutrino Experiment with a Xenon TPC (NEXT) searches for the neutrinoless double-beta (0¿ßß) decay of 136Xe using high-pressure xenon gas TPCs with electroluminescent amplification. A scaled-up version of this technology with about 1 tonne of enriched xenon could reach in less than 5 years of operation a sensitivity to the half-life of 0¿ßß decay better than 1027 years, improving the current limits by at least one order of magnitude. This prediction is based on a well-understood background model dominated by radiogenic sources. The detector concept presented here represents a first step on a compelling path towards sensitivity to the parameter space defined by the inverted ordering of neutrino masses, and beyond. [Figure not available: see fulltext.] © 2021, The Author(s)

    Ba+2 ion trapping using organic submonolayer for ultra-low background neutrinoless double beta detector

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    If neutrinos are their own antiparticles the otherwise-forbidden nuclear reaction known as neutrinoless double beta decay can occur. The very long lifetime expected for these exceptional events makes its detection a daunting task. In order to conduct an almost background-free experiment, the NEXT collaboration is investigating novel synthetic molecular sensors that may capture the Ba dication produced in the decay of certain Xe isotopes in a high-pressure gas experiment. The use of such molecular detectors immobilized on surfaces must be explored in the ultra-dry environment of a xenon gas chamber. Here, using a combination of highly sensitive surface science techniques in ultra-high vacuum, we demonstrate the possibility of employing the so-called Fluorescent Bicolor Indicator as the molecular component of the sensor. We unravel the ion capture process for these molecular indicators immobilized on a surface and explain the origin of the emission fluorescence shift associated to the ion trapping

    Boosting background suppression in the NEXT experiment through Richardson-Lucy deconvolution

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    Next-generation neutrinoless double beta decay experiments aim for half-life sensitivities of ~ 1027 yr, requiring suppressing backgrounds to &lt; 1 count/tonne/yr. For this, any extra background rejection handle, beyond excellent energy resolution and the use of extremely radiopure materials, is of utmost importance. The NEXT experiment exploits differences in the spatial ionization patterns of double beta decay and single-electron events to discriminate signal from background. While the former display two Bragg peak dense ionization regions at the opposite ends of the track, the latter typically have only one such feature. Thus, comparing the energies at the track extremes provides an additional rejection tool. The unique combination of the topology-based background discrimination and excellent energy resolution (1% FWHM at the Q-value of the decay) is the distinguishing feature of NEXT. Previous studies demonstrated a topological background rejection factor of ~ 5 when reconstructing electron-positron pairs in the 208Tl 1.6 MeV double escape peak (with Compton events as background), recorded in the NEXT-White demonstrator at the Laboratorio Subterráneo de Canfranc, with 72% signal efficiency. This was recently improved through the use of a deep convolutional neural network to yield a background rejection factor of ~ 10 with 65% signal efficiency. Here, we present a new reconstruction method, based on the Richardson-Lucy deconvolution algorithm, which allows reversing the blurring induced by electron diffusion and electroluminescence light production in the NEXT TPC. The new method yields highly refined 3D images of reconstructed events, and, as a result, significantly improves the topological background discrimination. When applied to real-data 1.6 MeV e-e+ pairs, it leads to a background rejection factor of 27 at 57% signal efficiency. [Figure not available: see fulltext.]. © 2021, The Author(s)

    A922 Sequential measurement of 1 hour creatinine clearance (1-CRCL) in critically ill patients at risk of acute kidney injury (AKI)

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