1,278 research outputs found

    Optimal high-dimensional entanglement concentration in the bipartite scenario

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    Considering pure quantum states, entanglement concentration is the procedure where from NN copies of a partially entangled state, a single state with higher entanglement can be obtained. Getting a maximally entangled state is possible for N=1N=1. However, the associated success probability can be extremely low while increasing the system's dimensionality. In this work, we study two methods to achieve a probabilistic entanglement concentration for bipartite quantum systems with a large dimensionality for N=1N=1, regarding a reasonably good probability of success at the expense of having a non-maximal entanglement. Firstly, we define an efficiency function Q\mathcal{Q} considering a tradeoff between the amount of entanglement (quantified by the I-Concurrence) of the final state after the concentration procedure and its success probability, which leads to solving a quadratic optimization problem. We found an analytical solution, ensuring that an optimal scheme for entanglement concentration can always be found in terms of Q\mathcal{Q}. Finally, a second method was explored, which is based on fixing the success probability and searching for the maximum amount of entanglement attainable. Both ways resemble the Procrustean method applied to a subset of the most significant Schmidt coefficients but obtaining non-maximally entangled states.Comment: 11 pages, 4 figure

    The relationship between mindfulness and emotional intelligence as a protective factor for healthcare professionals: systematic review

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    Emotional intelligence is an essential trait and skill for healthcare professionals. Mind fulness meditation has proved to be effective in increasing the wellbeing of those who practice it, leading to better mental health, self-care and job satisfaction. This paper aims to identify the recent evidence on the relationship between mindfulness and emotional intelligence among healthcare professionals and students. A systematic review was conducted including the databases PubMed, Cinhal, PsycINFO and Web of Science. The main variables were emotional intelligence skills and mindfulness practice. Data were extracted according to the following outcomes: authors, year of publication, country, study design, participants, mindfulness training intervention, tools used in data collection and main results. The following inclusion criteria were applied: peer-reviewed articles; published in English or Spanish; published between 2010 and 2020; quantitative methodology; a study population of healthcare professionals or students; the relationship with the aim of the study. The Joanna Briggs Institute criteria were followed for assessing the methodological quality of the selected studies. Three researchers were involved in the review. After the selection process, 10 studies were selected out of the 197 references initially identified. These studies revealed a positive relation ship between mindfulness and emotional intelligence, particularly the capacity to regulate emotions. Furthermore, mindfulness is negatively related to emotional exhaustion. Training interventions based on mindfulness have proved to be useful in promoting emotional balance, emotional awareness, emotional acceptance, emotion recognition, expressive suppression and a reduction in emotional exhaustion. This study could serve as a basis for further research on the benefits of emotional intelligence and practicing mindfulness for the bio-psycho-social welfare of healthcare professionals

    A Multi-Epoch Study of the Radio Continuum Emission of Orion Source I: Constraints on the Disk Evolution of a Massive YSO and the Dynamical History of Orion BN/KL

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    We present new 7mm continuum observations of Orion BN/KL with the VLA. We resolve the emission from the protostar radio Source I and BN at several epochs. Source I is highly elongated NW-SE, and remarkably stable in flux density, position angle, and overall morphology over nearly a decade. This favors the extended emission component arising from an ionized disk rather than a jet. We have measured the proper motions of Source I and BN for the first time at 43 GHz. We confirm that both sources are moving at high speed (12 and 26 km/s, respectively) approximately in opposite directions, as previously inferred from measurements at lower frequencies. We discuss dynamical scenarios that can explain the large motions of both BN and Source I and the presence of disks around both. Our new measurements support the hypothesis that a close (~50 AU) dynamical interaction occurred around 500 years ago between Source I and BN as proposed by Gomez et al. From the dynamics of encounter we argue that Source I today is likely to be a binary with a total mass on the order of 20 Msun, and that it probably existed as a softer binary before the close encounter. This enables preservation of the original accretion disk, though truncated to its present radius of ~50 AU. N-body numerical simulations show that the dynamical interaction between a binary of 20 Msun total mass (I) and a single star of 10 Msun mass (BN) may lead to the ejection of both and binary hardening. The gravitational energy released in the process would be large enough to power the wide-angle flow traced by H2 and CO emission in the BN/KL nebula. Assuming the proposed dynamical history is correct, the smaller mass for Source I recently estimated from SiO maser dynamics (>7 Msun) by Matthews et al., suggests that non-gravitational forces (e.g. magnetic) must play an important role in the circumstellar gas dynamics.Comment: 17 pages, 7 figures, 4 tables, accepted by Ap

    Comparative studies on lectin–carbohydrate interactions in low and high density homo- and heteroglycoclusters

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    12 páginas, 5 figuras, 3 tablas, 3 esquemas.A versatile synthetic procedure to construct series of high- and low-density homo- and heteroglycoclusters is reported. The binding properties of these synthetic multivalent glycoconjugates to concanavalin A (Con A), a model lectin, have been assessed by using a range of competitive and non-competitive binding assays including enzyme-linked lectin assays (ELLA), isothermal titration microcalorimetry (ITC) and surface plasmon resonance (SPR). In all cases, highly dense glycoclusters showed a substantial amplification of the lectin-binding strength in comparison with low-density counterparts. Interestingly, highly-dense glycoligand presentations, regardless of their homo- or heteroglycoligand pattern, furnished similar Con A binding properties, supporting the existence of a synergic effect (heterocluster effect) due to secondary interactions of “non-active” structural motifs in the presence of a certain density of “active” glycoligands.We thank the Spanish Ministerio de Educación y Ciencia (contracts number CTQ2006-15515-C02-01/BQUand CTQ2007-61180/PPQ) and the Junta de Andalucía for financial support.Peer reviewe

    Kinematic analysis of the Large Magellanic Cloud using Gaia DR3

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    Context: The high quality of the Gaia mission data is allowing to study the internal kinematics of the Large Magellanic Cloud (LMC) in unprecedented detail, providing insights on the non-axisymmetric structure of its disc. Aims: To define and validate an improved selection strategy to distinguish the LMC stars from the Milky Way foreground. To check the possible biases that assumed parameters or sample contamination from the Milky Way can introduce in the analysis of the internal kinematics of the LMC using Gaia data. Methods: Our selection is based on a supervised Neural Network classifier using as much as of the Gaia DR3 data as possible. We select three samples of candidate LMC stars with different degrees of completeness and purity; we validate them using different test samples and we compare them with the Gaia Collaboration paper sample. We analyse the resulting velocity profiles and maps, and we check how these results change when using also the line-of-sight velocities, available for a subset of stars. Results: The contamination in the samples from Milky Way stars affects basically the results for the outskirts of the LMC, and the absence of line-of-sight velocities does not bias the results for the kinematics in the inner disc. For the first time, we perform a kinematic analysis of the LMC using samples with the full three dimensional velocity information from Gaia DR3. Conclusions: The dynamics in the inner disc is mainly bar dominated; the kinematics on the spiral arm over-density seem to be dominated by an inward motion and a rotation faster than that of the disc in the piece of the arm attached to the bar; contamination of MW stars seem to dominate the outer parts of the disc and mainly affects old evolutionary phases; uncertainties in the assumed disc morphological parameters and line-of-sight velocity of the LMC can in some cases have significant effects. [ABRIDGED

    Short-Term Evaluation of Left Ventricular Mass and Function in Children With Growth Hormone Deficiency After Replacement Treatment

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    Background: Our study was designed to assess the effects of GHD on nutritional and metabolic parameters, brain natriuretic peptide (BNP) levels, and left ventricular mass (LVM) in prepubertal children and after short-term GH replacement therapy.Materials and Methods: This prospective study enrolled 81 children. We compared 40 GHD children (16 males and 24 females) to 41 healthy children (control group) (18 males and 23 females). All subjects were at Tanner Stage I (aged 7–11 years). At the baseline, a blood sample was drawn and echocardiographic images were obtained. These tests were repeated on the GHD subjects after 6 months of GH replacement therapy. Body surface, weight, size, blood pressure, heart rate, glucose, insulin, HOMA-IR, HOMA-β, QUICKI, cholesterol, HDLc, LDLc, triglycerides, IGF1, and IGFBP3 were measured. Indexed LVM, diastolic and systolic diameter (dD-sD), diastolic and systolic LV function, isovolumic relaxation time, right ventricle function, and BNP levels were obtained through echocardiography. These parameters were correlated to growth factors. Data were analyzed using Student's t-test or U-Mann–Whitney-test and Pearson's correlation, considering p < 0.05 to be significant.Results: Indexed LVM was smaller in GHD patients than in controls, whereas diastolic and systolic functions, BNP, metabolic, and nutritional profiles were similar. After treatment, nutritional and metabolic profiles significantly improved, though diastolic and systolic functions did not seem to have changed. There was a significant increase in LVM. Indexed LVM was similar to that of controls. Significant correlations were obtained between LVM-IGF1 and sD-IGFBP3.Conclusions: GHD in childhood is associated with a lower indexed LVM. In the short-term, GH increases the indexed LVM, while maintaining normal systolic and diastolic functions, BNP, and an improved lipid profile

    Dietilditiocarbamato sódico: acciones hipoglucemiante y antioxidante

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    The diethyldithiocarbamates have been studied in several industries and investigation fields. We have iniciated the study of Sodium diethyldithiocarbamate from antioxidant and hipoglycemic view points. This carbamato decreased glucose levels in rats (800 mg/ kg per os). The antioxidant activity, in yitro, showed similar as whith ascórbic acid.Los dietilditiocarbamatos vienen siendo objeto de estudio en numerosos campos de la industria e investigación. Se ha iniciado el estudio del dietilditiocarbamato sódico desde los puntos de vista de su actividad antioxidante e hipoglucemiante. Dicho carbamato, administrado a ratas (800 mg/kg V.O.) provocó descensos en los niveles de glucosa en sangre. In yitro, su actividad antioxidante se halló dentro del rango del ácido ascórbico

    Using radio astronomical receivers for molecular spectroscopic characterization in astrochemical laboratory simulations: A proof of concept

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    We present a proof of concept on the coupling of radio astronomical receivers and spectrometers with chemical reactorsand the performances of the resulting setup for spectroscopy and chemical simulations in laboratory astrophysics. Several experiments including cold plasma generation and UV photochemistry were performed in a 40\,cm long gas cell placed in the beam path of the Aries 40\,m radio telescope receivers operating in the 41-49 GHz frequency range interfaced with fast Fourier transform spectrometers providing 2 GHz bandwidth and 38 kHz resolution. The impedance matching of the cell windows has been studied using different materials. The choice of the material and its thickness was critical to obtain a sensitivity identical to that of standard radio astronomical observations. Spectroscopic signals arising from very low partial pressures of CH3OH, CH3CH2OH, HCOOH, OCS,CS, SO2 (<1E-03 mbar) were detected in a few seconds. Fast data acquisition was achieved allowing for kinetic measurements in fragmentation experiments using electron impact or UV irradiation. Time evolution of chemical reactions involving OCS, O2 and CS2 was also observed demonstrating that reactive species, such as CS, can be maintained with high abundance in the gas phase during these experiments.Comment: Accepted for publication in Astronomy and Astrophysics in September 21, 2017. 16 pages, 18 figure
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