3,232 research outputs found
The Gaia-ESO Survey: dynamics of ionized and neutral gas in the Lagoon nebula (M8)
We present a spectroscopic study of the dynamics of the ionized and neutral
gas throughout the Lagoon nebula (M8), using VLT/FLAMES data from the Gaia-ESO
Survey. We explore the connections between the nebular gas and the stellar
population of the associated star cluster NGC6530. We characterize through
spectral fitting emission lines of H-alpha, [N II] and [S II] doublets, [O
III], and absorption lines of sodium D doublet, using data from the
FLAMES/Giraffe and UVES spectrographs, on more than 1000 sightlines towards the
entire face of the Lagoon nebula. Gas temperatures are derived from line-width
comparisons, densities from the [S II] doublet ratio, and ionization parameter
from H-alpha/[N II] ratio. Although doubly-peaked emission profiles are rarely
found, line asymmetries often imply multiple velocity components along the line
of sight. This is especially true for the sodium absorption, and for the [O
III] lines. Spatial maps for density and ionization are derived, and compared
to other known properties of the nebula and of its massive stars 9 Sgr,
Herschel 36 and HD 165052 which are confirmed to provide most of the ionizing
flux. The detailed velocity fields across the nebula show several expanding
shells, related to the cluster NGC6530, the O stars 9 Sgr and Herschel 36, and
the massive protostar M8East-IR. The origins of kinematical expansion and
ionization of the NGC6530 shell appear to be different. We are able to put
constrains on the line-of-sight (relative or absolute) distances between some
of these objects and the molecular cloud. The large obscuring band running
through the middle of the nebula is being compressed by both sides, which might
explain its enhanced density. We also find an unexplained large-scale velocity
gradient across the entire nebula. At larger distances, the transition from
ionized to neutral gas is studied using the sodium lines.Comment: 26 pages, 31 figures, accepted on Astronomy and Astrophysics journa
Simple and fast orotracheal intubation procedure in rat
Introduction: Endotracheal intubation in the rat is difficult because of extremely small size of anatomical structures (oral cavity, epiglottis and vocal cords), small inlet for an endotracheal tube and the lack of proper techniacal instruments. Matherial and Methods: In this study we used seventy rats weighthing 400-500 g. The equipment needed for intubation was an operating table, a longish of cotton, a cotton tip, orotracheal tube, neonatal laryngoscope KTR4, small animal ventilator, and isoflurane for inhalation anaesthesia. Premedication was carried out by medetomidine hydrochloride 1 mg/mL; then, thanks to a closed glass chamber, a mixture of oxygen and isoflurane was administered. By means of neonatal laryngoscope the orotracheal tube was advanced into the oral cavity untile the wire guide was visualized trough the vocal cords; then it was passed through them. The tube was introduced directly into into the larynx over the wire guide; successively, the guide was removed and the tube placed into the trachea. Breathing was confirmed using a glove, cut at the end of a finger, simulating a small ballon. Conclusions: We believe that our procedure is easier and faster than those previously reported in scientific literature. (www.actabiomedica.it
Tetracyclines in COVID-19 patients quarantined at home: Literature evidence supporting real-world data from a multicenter observational study targeting inflammatory and infectious dermatoses
Tetracyclines (TetraC) are widely used in dermatology for both inflammatory and infectious dermatoses; recently both in vivo and in vitro studies started to suggest also a potential antiviral effect. During COVID-19 outbreak, several dermatological patients contracted SARS-CoV-2 experiencing only mild symptoms, but no protocol were approved. A multicenter prospective observational study that enrolled COVID-19 patients visited with teledermatology and undergoing TetraC was performed. About 38 adult outpatients (M/F: 20/18, age 42.6 years [21-67]) were enrolled. During the TetraC treatment, symptoms resolved in all patients within 10 days. Remarkably, ageusia and anosmia disappeared in the first week of TetraC treatment. TetraC seem a promising drug to treat COVID-19 outpatients with mild symptoms
Adhesion State Estimation for Electrostatic Gripper Based on Online Capacitance Measure
Electroadhesion is a suitable technology for developing grippers for applications where fragile, compliant or variable shape objects need to be grabbed and where a retention action is typically preferred to a compression force. This article presents a self-sensing technique for electroadhesive devices (EAD) based on the capacitance measure. Specifically, we demonstrate that measuring the variation of the capacitance between electrodes of an EAD during the adhesion can provide useful information to automatically detect the successful grip of an object and the possible loss of adhesion during manipulation. To this aim, a dedicated electronic circuit is developed that is able to measure capacitance variations while the high voltage required for the adhesion is activated. A test bench characterization is presented to evaluate the self-sensing of capacitance during different states: (1) the EAD is far away from the object to be grasped; (2) the EAD is in contact with the object, but the voltage is not active (i.e., no adhesion); and (3) the EAD is activated and attached to the object. Correlation between the applied voltage, object material and shape and capacitance is made. The self-sensing EAD is then demonstrated in a closed-loop robotic application that employs a robot manipulator arm to pick and place objects of different kinds
The Gaia-ESO Survey: Tracing interstellar extinction
Large spectroscopic surveys have enabled in the recent years the computation
of three-dimensional interstellar extinction maps thanks to accurate stellar
atmospheric parameters and line-of-sight distances. Such maps are complementary
to 3D maps extracted from photometry, allowing a more thorough study of the
dust properties. Our goal is to use the high-resolution spectroscopic survey
Gaia-ESO in order to obtain with a good distance resolution the interstellar
extinction and its dependency as a function of the environment and the
Galactocentric position. We use the stellar atmospheric parameters of more than
5000 stars, obtained from the Gaia-ESO survey second internal data release, and
combine them with optical (SDSS) and near-infrared (VISTA) photometry as well
as different sets of theoretical stellar isochrones, in order to calculate
line-of-sight extinction and distances. The extinction coefficients are then
compared with the literature to discuss their dependancy on the stellar
parameters and position in the Galaxy. Within the errors of our method, our
work does not show that there is any dependence of the interstellar extinction
coefficient on the atmospheric parameters of the stars. We do not find any
evidence of the variation of E(J-H)/E(J-K) with the angle from the Galactic
centre nor with Galactocentric distance. This suggests that we are dealing with
a uniform extinction law in the SDSS ugriz bands and the near-IR JHKs bands.
Therefore, extinction maps using mean colour-excesses and assuming a constant
extinction coefficient can be used without introducing any systematic errors.Comment: 13 pages, 14 figures, 1 Appendix accepted for publication in
Astronomy&Astrophysic
The colors of our brain: an integrated approach for dimensionality reduction and explainability in fMRI through color coding (i-ECO)
Evidenze scientifiche ed insegnamento della lettura. Perché una alfabetizzazione fono-sillabica strutturata è necessaria per tutti i bambini
Nonostante la ricerca abbia acquisito esaustive evidenze sull’apprendimento della lettura e scrittura
dimostrando la necessitĂ che il bambino acquisisca il principio alfabetico di conversione grafema-
fonema in modo progressivo e sistematico, la maggior parte dei testi in adozione che vengono
presentati agli insegnanti disconoscono o relegano in secondo piano tale riferimento e prediligono
nuove forme di globalismo esteriore e dispersivo.
In questo lavoro si sperimenta un programma (ALFABETO 140), elaborato secondo un approccio
fono-sillabico, in coerenza con le evidenze acquisite e con i criteri dell’alfabetizzazione strutturata.
La sperimentazione condotta a livello nazionale mostra come un programma del genere consenta
ai bambini del Gruppo Sperimentale (GS) di ottenere risultati significativamente piĂą alti di quelli
del Gruppo di controllo (GC), una significativa riduzione della percentuale dei soggetti a rischio di
dislessia ed un ottimo apprezzamento da parte degli insegnanti che lo hanno applicato.
Il lavoro si conclude sottolineando la necessitĂ che in tutte le scuole si applichino programmi di
questo tipo necessari per tutti i bambini e che anche a livello istituzionale si intervenga per risolvere
l’ambiguità esistente nelle indicazioni ministeriali che, pur segnalando l’opportunità di metodi fono-
sillabici per soggetti a rischio di DSA, lasciano invece libertĂ per gli altri soggetti
Rubin LSST observing strategies to maximize volume and uniformity coverage of Star Forming Regions in the Galactic Plane
A complete map of the youngest stellar populations of the Milky Way in the
era of all-sky surveys, is one of the most challenging goals in modern
astrophysics. The characterisation of the youngest stellar component is crucial
not only for a global overview of the Milky Way structure, of the Galactic thin
disk, and its spiral arms, but also for local studies. In fact, the
identification of the star forming regions (SFRs) and the comparison with the
environment in which they form are also fundamental to put them in the context
of the surrounding giant molecular clouds and to understand still unknown
physical mechanisms related to the star and planet formation processes. In 10
yrs of observations, Vera C. Rubin Legacy Survey of Space and Time (Rubin-LSST)
will achieve an exquisite photometric depth that will allow us to significantly
extend the volume within which we will be able to discover new SFRs and to
enlarge the domain of a detailed knowledge of our own Galaxy. We describe here
a metrics that estimates the total number of young stars with ages t < 10 Myr
and masses >0.3M that will be detected with the Rubin LSST observations
in the gri bands at a 5 {\sigma} magnitude significance. We examine the results
of our metrics adopting the most recent simulated Rubin-LSST survey strategies
in order to evaluate the impact that different observing strategies might have
on our science case.Comment: 11 pages, 5 figures, 1 table; accepted for publication in The
Astrophysical Journal Supplement Serie
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