256 research outputs found
Faculty Entrustment of Students in the Core Clerkships: A Comparison between the Longitudinal Integrated Clerkship and the Block Clerkship
INTRODUCTION: Entrustable Professional Activities (EPAs) have been proposed for use in undergraduate medical education. The ability of faculty to entrust students with EPAs may differ between Longitudinal Integrated Clerkships (LICs) and traditional block clerkships.
METHODS: Participants were core clerkship faculty, 64 in a LIC and 31 in a sequential block clerkship. We administered a web-based survey at the end of the core clerkship year to measure preceptors’ typical entrustment (on a scale of 0–10) in students for the 13 American Association of Medical Colleges Core EPAs. We compared entrustment between LIC and block faculty using a Mann-Whitney test.
RESULTS:LIC faculty were more entrusting of students than block faculty in 12 out of 13 Core EPAs (p
DISCUSSION: LIC faculty were more likely than block clerkship faculty to entrust core clerkship students with performance of most EPAs. This finding is likely the result of LIC faculty having increased familiarity with student abilities because of the continuity of supervision and education inherent to LIC. More research is needed to ascertain the specific features of longitudinal clerkships that increase faculty entrustment of students.
CONCLUSIONS: Longitudinal educational experiences may facilitate the assessment of medical students with EPAs
Stellar Atmospheric Parameters for Cool Dwarfs in Gaia DR3
We provide a catalogue of atmospheric parameters for 1,806,921 cool dwarfs
from Gaia DR3 which lie within the range covered by LAMOST cool dwarf
spectroscopic parameters: 3200 K < T_{eff}< 4300 K, -0.8 < [M/H] < 0.2 dex, and
4.5 <log{g} < 5.5 dex. Our values are derived based on Machine Learning models
trained with multi-band photometry corrected for dust. The photometric data
comprises of optical from SDSS r, i, z bands, near-infrared from 2MASS J, H, K
and mid-infrared from ALLWISE W1, W2. We used both random forest and LightGBM
machine learning models and found similar results from both with an error
dispersion of 68 K, 0.22 dex, and 0.05 dex for T_{eff}, [M/H], and log {g},
respectively. Assessment of the relative feature importance of different
photometric colors indicated W1 -- W2 as most sensitive to both T_{eff} and
log{g}, with J -- H most sensitive to [M/H]. We find that our values show a
good agreement with APOGEE, but are significantly different to those provided
as part of Gaia DR3.Comment: 14 pages, 12 figures, accepted by ApJ
Stellar Atmospheric Parameters for Cool Dwarfs in Gaia Data Release 3
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY), https://creativecommons.org/licenses/by/4.0/We provide a catalog of atmospheric parameters for 1,806,921 cool dwarfs from Gaia Data Release 3 (DR3) that lie within the range covered by LAMOST cool dwarf spectroscopic parameters: 3200 K < T eff < 4300 K, −0.8 < [M/H] < 0.2 dex, and 4.5 < log g < 5.5 dex. Our values are derived based on machine-learning models trained with multiband photometry corrected for dust. The photometric data comprise optical data from the Sloan Digital Sky Survey r, i, and z bands, near-infrared data from the Two Micron All Sky Survey J, H, and K bands, and mid-infrared data from the ALLWISE W1 and W2 bands. We used both random forest and light gradient boosting machine machine-learning models and found similar results from both, with an error dispersion of 68 K, 0.22 dex, and 0.05 dex for T eff, [M/H], and log g, respectively. Assessment of the relative feature importance of different photometric colors indicated W1 − W2 as most sensitive to both T eff and log g, with J − H being most sensitive to [M/H]. We find that our values show a good agreement with the Apache Point Observatory Galactic Evolution Experiment, but are significantly different to those provided as part of Gaia DR3.Peer reviewe
Neuroendocrine Response to Exogenous Ghrelin Administration, Combined With Alcohol, in Heavy-Drinking Individuals: Findings From a Randomized, Double-Blind, Placebo-Controlled Human Laboratory Study
Background: Accumulating evidence has established a role for the orexigenic hormone ghrelin in alcohol-seeking behaviors. Accordingly, the ghrelin system may represent a potential pharmacotherapeutic target for alcohol use disorder. Ghrelin modulates several neuroendocrine pathways, such as appetitive, metabolic, and stress-related hormones, which are particularly relevant in the context of alcohol use. The goal of the present study was to provide a comprehensive assessment of neuroendocrine response to exogenous ghrelin administration, combined with alcohol, in heavy-drinking individuals.
Methods: This was a randomized, crossover, double-blind, placebo-controlled human laboratory study, which included 2 experimental alcohol administration paradigms: i.v. alcohol self-administration and i.v. alcohol clamp. Each paradigm consisted of 2 counterbalanced sessions of i.v. ghrelin or placebo administration. Repeated blood samples were collected during each session, and peripheral concentrations of the following hormones were measured: leptin, glucagon-like peptide-1, pancreatic polypeptide, gastric inhibitory peptide, insulin, insulin-like growth factor-1, cortisol, prolactin, and aldosterone.
Results: Despite some statistical differences, findings were consistent across the 2 alcohol administration paradigms: i.v. ghrelin, compared to placebo, increased blood concentrations of glucagon-like peptide-1, pancreatic polypeptide, cortisol, and prolactin, both acutely and during the whole session. Lower levels of leptin and higher levels of aldosterone were also found during the ghrelin vs placebo session.
Conclusion: These findings, gathered from a clinically relevant sample of heavy-drinking individuals with alcohol use disorder, provide a deeper insight into the complex interplay between ghrelin and appetitive, metabolic, and stress-related neuroendocrine pathways in the context of alcohol use
Ultracool dwarfs identified using spectra in LAMOST DR7
In this work, we identify 734 ultracool dwarfs with a spectral type of M6 or
later, including one L0. Of this sample, 625 were studied spectroscopically for
the first time. All of these ultracool dwarfs are within 360~pc, with a
\textit{Gaia} G magnitude brighter than ~19.2 mag. By studying the spectra and
checking their stellar parameters (Teff, logg, and [FeH] derived with the
LAMOST pipeline, we found their cool red nature and their metallicity to be
consistent with the nature of Galactic thin-disk objects. Furthermore, 77 of
them show lithium absorption lines at 6708A, further indicating their young
ages and substellar nature. Kinematics obtained through LAMOST radial
velocities, along with the proper motion and parallax data from Gaia EDR3, also
suggest that the majority of our targets are thin-disk objects. Kinematic ages
were estimated through the relationship between the velocity dispersion and the
average age for a certain population. Moreover, we identified 35 binaries, with
6 of them reported as binaries for the first time.Comment: 13 pages, 11 figures, published in A&A, Volume 660. A38 (2022
CP violating neutrino oscillation and uncertainties in Earth matter density
We propose a statistical formulation to estimate possible errors in long
baseline neutrino oscillation experiments caused by uncertainties in the Earth
matter density. A quantitative investigation of the effect is made on the CP
asymmetry in future neutrino factory experiments.Comment: Latex, 10 pages, 5 figure
J/psi suppression at forward rapidity in Au+Au collisions at sqrt(s_NN)=39 and 62.4 GeV
We present measurements of the J/psi invariant yields in sqrt(s_NN)=39 and
62.4 GeV Au+Au collisions at forward rapidity (1.2<|y|<2.2). Invariant yields
are presented as a function of both collision centrality and transverse
momentum. Nuclear modifications are obtained for central relative to peripheral
Au+Au collisions (R_CP) and for various centrality selections in Au+Au relative
to scaled p+p cross sections obtained from other measurements (R_AA). The
observed suppression patterns at 39 and 62.4 GeV are quite similar to those
previously measured at 200 GeV. This similar suppression presents a challenge
to theoretical models that contain various competing mechanisms with different
energy dependencies, some of which cause suppression and others enhancement.Comment: 365 authors, 10 pages, 11 figures, 4 tables. Submitted to Phys. Rev.
C. Plain text data tables for the points plotted in figures for this and
previous PHENIX publications are (or will be) publicly available at
http://www.phenix.bnl.gov/papers.htm
Medium modification of jet fragmentation in Au+Au collisions at sqrt(s_NN)=200 GeV measured in direct photon-hadron correlations
The jet fragmentation function is measured with direct photon-hadron
correlations in p+p and Au+Au collisions at sqrt(s_NN)=200 GeV. The p_T of the
photon is an excellent approximation to the initial p_T of the jet and the
ratio z_T=p_T^h/p_T^\gamma is used as a proxy for the jet fragmentation
function. A statistical subtraction is used to extract the direct photon-hadron
yields in Au+Au collisions while a photon isolation cut is applied in p+p. I_
AA, the ratio of jet fragment yield in Au+Au to that in p+p, indicates
modification of the jet fragmentation function. Suppression, most likely due to
energy loss in the medium, is seen at high z_T. The fragment yield at low z_T
is enhanced at large angles. Such a trend is expected from redistribution of
the lost energy into increased production of low-momentum particles.Comment: 562 authors, 70 insitutions, 8 pages, and 3 figures. Submitted to
Phys. Rev. Lett. v2 has minor changes to improve clarity. Plain text data
tables for the points plotted in figures for this and previous PHENIX
publications are (or will be) publicly available at
http://www.phenix.bnl.gov/papers.htm
Nuclear matter effects on production in asymmetric Cu+Au collisions at = 200 GeV
We report on production from asymmetric Cu+Au heavy-ion collisions
at =200 GeV at the Relativistic Heavy Ion Collider at both
forward (Cu-going direction) and backward (Au-going direction) rapidities. The
nuclear modification of yields in CuAu collisions in the Au-going
direction is found to be comparable to that in AuAu collisions when plotted
as a function of the number of participating nucleons. In the Cu-going
direction, production shows a stronger suppression. This difference is
comparable in magnitude and has the same sign as the difference expected from
shadowing effects due to stronger low- gluon suppression in the larger Au
nucleus. The relative suppression is opposite to that expected from hot nuclear
matter dissociation, since a higher energy density is expected in the Au-going
direction.Comment: 349 authors, 10 pages, 4 figures, and 4 tables. Submitted to Phys.
Rev. C. For v2, fixed LaTeX error in 3rd-to-last sentence. Plain text data
tables for the points plotted in figures for this and previous PHENIX
publications are (or will be) publicly available at
http://www.phenix.bnl.gov/papers.htm
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