1,407 research outputs found
Optimal high-dimensional entanglement concentration in the bipartite scenario
Considering pure quantum states, entanglement concentration is the procedure
where from copies of a partially entangled state, a single state with
higher entanglement can be obtained. Getting a maximally entangled state is
possible for . 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 , regarding a
reasonably good probability of success at the expense of having a non-maximal
entanglement. Firstly, we define an efficiency function
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 .
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
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
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
Kinematic analysis of the Large Magellanic Cloud using Gaia DR3
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
Comparative studies on lectin–carbohydrate interactions in low and high density homo- and heteroglycoclusters
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
Short-Term Evaluation of Left Ventricular Mass and Function in Children With Growth Hormone Deficiency After Replacement Treatment
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
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
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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