1,005 research outputs found

    Quark mass dependence of the Ds0(2317)D_{s0}^*(2317)

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    We determine the quark mass dependence - light and heavy - of the Ds0(2317)D_{s0}(2317) properties, such as, mass, coupling to DKDK, scattering lengths and compositeness, from a global analysis of DKDK energy levels from LQCD. In particular, we analyze the HSC energy levels for DKDK scattering in I=0I=0 for different boosts and two pion masses. The formalism is based in the local hidden-gauge interaction of Weinberg-Tomozawa type which respects chiral and heavy quark spin symmetries, supplemented by a term that takes into account the DKDK coupling to a bare csˉc\bar{s} component. The isospin violating decay of the Ds0(2317)Ds+π0D_{s0}(2317)\to D_{s}^+\pi^0 is also evaluated

    Proton charge radius extraction from muon scattering at MUSE using dispersively improved chiral effective field theory

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    The MUSE experiment at Paul Scherrer Institute will perform the first measurement of low-energy muon-proton elastic scattering (muon lab momenta 115-210 MeV) with the aim of determining the proton charge radius. We study the prospects for the proton radius extraction using the theoretical framework of Dispersively Improved Chiral Effective Field Theory (DIχ\chiEFT). It connects the proton radii with the finite-Q2Q^2 behavior of the form factors through complex analyticity and enables the use of data up to Q2Q^2 \sim 0.1 GeV2^2 for radius extraction. We quantify the sensitivity of the μp\mu p cross section to the proton charge radius, the theoretical uncertainty of the cross section predictions, and the size of two-photon exchange corrections. We find that the optimal kinematics for radius extraction at MUSE is at momenta 210 MeV and Q2Q^2 \sim 0.05-0.08 GeV2^2. We compare the performance of electron and muon scattering in the same kinematics. As a byproduct, we obtain explicit predictions for the μp\mu p and epep cross sections at MUSE as functions of the assumed value of the proton radius.Comment: 12 pages, 12 figure

    Metallo-dielectric core-shell nanospheres as building blocks for optical three-dimensional isotropic negative-index metamaterials

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    Materials showing electromagnetic properties that are not attainable in naturally occurring media, so-called metamaterials, have been lately, and still are, among the most active topics in optical and materials physics and engineering. Among these properties, one of the most attractive ones is the subdiffraction resolving capability predicted for media having an index of refraction of -1. Here, we propose a fully three-dimensional, isotropic metamaterial with strong electric and magnetic responses in the optical regime, based on spherical metallo-dielectric core-shell nanospheres. The magnetic response stems from the lowest, magnetic-dipole resonance of the dielectric shell with a high refractive index, and can be tuned to coincide with the plasmon resonance of the metal core, responsible for the electric response. Since the response does not originate from coupling between structures, no particular periodic arrangement needs to be imposed. Moreover, due to the geometry of the constituents, the metamaterial is intrinsically isotropic and polarization independent. It could be realized with current fabrication techniques with materials such as silver (core) and silicon or germanium (shell). For these particular realistic designs, the metamaterials present a negative index in the range of 1.2-1.55οm. © IOP Publishing Ltd and Deutsche Physikalische Gesellschaft.The authors acknowledge support from the Spain Ministerio de Ciencia e Innovacion´ through the Consolider-Ingenio project EMET (CSD2008-00066) and NANOPLAS (FIS2009- 11264) and from the Comunidad de Madrid (grant MICROSERES P2009/TIC-1476). RP-D acknowledges support from CSIC through a JAE-Pre grantPeer Reviewe

    Fano-like interference of plasmon resonances at a single rod-shaped nanoantenna

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    Single metallic nanorods acting as half-wave antennas in the optical range exhibit an asymmetric, multi-resonant scattering spectrum that strongly depends on both their length and dielectric properties. Here we show that such spectral features can be easily understood in terms of Fano-like interference between adjacent plasmon resonances. On the basis of analytical and numerical results for different geometries, we demonstrate that Fano resonances may appear for such single-particle nanoantennas provided that interacting resonances overlap in both spatial and frequency domains.Comment: 18 pages, 9 figure

    Testosterone recovery after androgen deprivation therapy in prostate cancer: building a predictive model

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    Purpose: To analyze the variability, associated actors, and the design of nomograms for individualized testosterone recovery after cessation of androgen deprivation therapy (ADT). Materials and Methods: A longitudinal study was carried out with 208 patients in the period 2003 to 2019. Castrated and normogonadic testosterone levels were defined as 0.5 and 3.5 ng/mL, respectively. The cumulative incidence curve described the recovery of testosterone. Univariate and multivariate analyzes were performed to predict testosterone recovery with candidate prognostic factors prostate-specific antigen at diagnosis, clinical stage, Gleason score from biopsy, age at cessation of ADT, duration of ADT, primary therapy and use of LHRH (luteinizing hormone-releasing hormone) agonists. Results: The median follow-up duration in the study was 80 months (interquartile range, 49–99 mo). Twenty-five percent and 81% of patients did not recover the castrate and normogonadic levels, respectively. Duration of ADT and age at ADT cessation were significant predictors of testosterone recovery. We built two nomograms for testosterone recovery at 12, 24, 36, and 60 months. The castration recovery model had good calibration. The C-index was 0.677, with area under the receiver operating characteristic curve (AUC-ROC) of 0.736, 0.783, 0.782, and 0.780 at 12, 24, 36, and 60 months, respectively. The normogonadic recovery model overestimated the higher values of probability of recovery. The Cindex was 0.683, with AUC values of 0.812, 0.711, 0.708 and 0.693 at 12, 24, 36, and 60 months, respectively. Conclusions: Depending on the age of the patient and the length of treatment, clinicians may stop ADT and the castrated testosterone level will be maintained or, if the course of treatment has been short, we can estimate if it will return to normogonadic levels

    Comparative analysis of the serve in volleyball between the spanish championships 2005-2010

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    El objetivo fue analizar los cambios que ha experimentado el saque desde el Campeonato de España cadete masculino de 2005 al de 2010. Mediante la observación sistemática se analizaron 1594 acciones, en las cuales se midieron las siguientes variables: zona de origen, eficacia, tipo de saque, zona de recepción, función del receptor, dirección y temporalidad. Los resultados reflejaron que en los últimos años, el saque realizado por jugadores de categoría de formación ha sufrido modificaciones relevantes, tales como, mejora de la eficacia, incremento del empleo del saque en salto, y realización del saque con un carácter más táctico. Pese a la mayor aproximación del saque a los perfiles existentes en alto nivel, se recomienda que el saque de voleibol en categorías de formación se entrene en función de las características y nivel de los jugadores, evitando el mimetismo de lo que acontece en alto nivelThe aim of this research was to analyze the changes in the characteristics of the serve between the male Under-16 Spanish Championships that took place in 2005 and 2010. Through systematic observation 1594 actions were analyzed. The measured variables were: serve zone, effectiveness, serve type, reception zone, in-game role of the receptor, serve direction and timing. The results showed that in recent years, the serve performed by players at training stages has undergone significant changes, such as improved efficiency, increased use of jump serve, and execution of the serve with a more tactical role. Despite of the closest approach of the serve to the existing high level profiles, it is recommended to train the serve in volleyball training stages according to the characteristics and level of players, avoiding mimicry of what happens at a high levelEste trabajo ha sido realizado gracias al apoyo del Programa de Formación de Personal Investigador (FPI) de la Consejería de Empleo, Empresa e Innovación del Gobierno de Extremadura (España), y gracias al Ministerio de Ciencia e Innovación en el Plan Nacional de I+D+I 2008-2011 (ref. DEP2011-27503

    Production of new neutron-rich isotopes of heavy elements in fragmentation reactions of 238^{238}U projectiles at 1 A GeV

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    The production of heavy neutron-rich nuclei has been investigated using cold fragmentation reactions of 238^{238}U projectiles at relativistic energies. The experiment performed at the high-resolving-power magnetic spectrometer FRS at GSI allowed to identify 45 new heavy neutron-rich nuclei: 205^{205}Pt, 207210^{207-210}Au, 211216^{211-216}Hg, 213217^{213-217}Tl, 215220^{215-220}Pb, 219224^{219-224}Bi, 221227^{221-227}Po, 224229^{224-229}At, 229231^{229-231}Rn and 233^{233}Fr. The production cross sections of these nuclei were also determined and used to benchmark reaction codes that predict the production of nuclei far from stability.Comment: 5 pages, 2 figure

    Uncontrolled Donation after Circulatory Death: European practices and recommendations for the development and optimization of an effective programme.

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    Shortage of organs has made a global interest for donation after circulatory death (DCD) to re-emerge. While controlled DCD (cDCD) has been progressively increasing, uncontrolled DCD (uDCD) has only been developed in a few settings.1 This activity is quantitatively important in France and Spain, although it has also been reported in other European countries, as Austria, Belgium, Italy, the Netherlands, and recently in Russia.2,3 uDCD protocols have allowed the transplantation of a significant number of kidneys, livers and lungs at these countries.3 Excellent graft survival has been reported in kidney transplantation from uDCD, in spite of an increased incidence of delayed graft function (DGF).4,5,6,7,8,9,10,11,12,13,14,1516 Albeit promising, results with liver transplants obtained in uDCD protocols do not consistently provide similar outcomes compared with livers from donors after brain death (DBD), mainly due to a higher incidence of primary graft dysfunction and non-function and biliary complications.17,18,19,20,21,22 Lung transplantation is still facing limited experience, but preliminary results are encouraging.pre-print938 K

    Exploiting distant homologues for phasing through the generation of compact fragments, local fold refinement and partial solution combination.

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    Macromolecular structures can be solved by molecular replacement provided that suitable search models are available. Models from distant homologues may deviate too much from the target structure to succeed, notwithstanding an overall similar fold or even their featuring areas of very close geometry. Successful methods to make the most of such templates usually rely on the degree of conservation to select and improve search models. ARCIMBOLDO_SHREDDER uses fragments derived from distant homologues in a brute-force approach driven by the experimental data, instead of by sequence similarity. The new algorithms implemented in ARCIMBOLDO_SHREDDER are described in detail, illustrating its characteristic aspects in the solution of new and test structures. In an advance from the previously published algorithm, which was based on omitting or extracting contiguous polypeptide spans, model generation now uses three-dimensional volumes respecting structural units. The optimal fragment size is estimated from the expected log-likelihood gain (LLG) values computed assuming that a substructure can be found with a level of accuracy near that required for successful extension of the structure, typically below 0.6 Å root-mean-square deviation (r.m.s.d.) from the target. Better sampling is attempted through model trimming or decomposition into rigid groups and optimization through Phaser's gyre refinement. Also, after model translation, packing filtering and refinement, models are either disassembled into predetermined rigid groups and refined (gimble refinement) or Phaser's LLG-guided pruning is used to trim the model of residues that are not contributing signal to the LLG at the target r.m.s.d. value. Phase combination among consistent partial solutions is performed in reciprocal space with ALIXE. Finally, density modification and main-chain autotracing in SHELXE serve to expand to the full structure and identify successful solutions. The performance on test data and the solution of new structures are described
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