70 research outputs found
Identification of the most vulnerable populations in the psychosocial sphere: a cross-sectional study conducted in Catalonia during the strict lockdown imposed against the COVID-19 pandemic.
Design and objectives A cross-sectional study to evaluate the impact of COVID-19 on the psychosocial sphere in both the general population and healthcare workers (HCWs). Methods The study was conducted in Catalonia (Spain) during the first wave of the COVID-19 pandemic when strict lockdown was in force. The study population included all people aged over 16 years who consented to participate in the study and completed the survey, in this case a 74-question questionnaire shared via social media using snowball sampling. A total of 56 656 completed survey questionnaires were obtained between 3 and 19 April 2020. The primary and secondary outcome measures included descriptive statistics for the non-psychological questions and the psychological impact of the pandemic, such as depression, anxiety, stress and post-traumatic stress disorder question scores. Results A n early and markedly negative impact on family finances, fear of working with COVID-19 patients and ethical issues related to COVID-19 care among HCWs was observed. A total of seven target groups at higher risk of impaired mental health and which may therefore benefit from an intervention were identified, namely women, subjects aged less than 42 years, people with a care burden, socioeconomically deprived groups, people with unskilled or unqualified jobs, patients with COVID-19 and HCWs working with patients with COVID-19. Conclusions Active implementation of specific strategies to increase resilience and to prepare an adequate organisational response should be encouraged for the seven groups identified as high risk and susceptible to benefit from an intervention
EPIC 219388192 b - an inhabitant of the brown dwarf desert in the Ruprecht 147 open cluster
We report the discovery of EPIC 219388192 b, a transiting brown dwarf in a
5.3-day orbit around a member star of Ruprecht-147, the oldest nearby open
cluster association, which was photometrically monitored by K2 during its
Campaign 7. We combine the K2 time-series data with ground-based adaptive
optics imaging and high resolution spectroscopy to rule out false positive
scenarios and determine the main parameters of the system. EPIC 219388192 b has
a radius of =~ and mass of
=~, yielding a mean density of
~. The host star is nearly a Solar twin with
mass =~, radius
=~, effective temperature
=~K and iron abundance [Fe/H]=~dex.
Its age, spectroscopic distance, and reddening are consistent with those of
Ruprecht-147, corroborating its cluster membership. EPIC 219388192 b is the
first brown dwarf with precise determinations of mass, radius and age, and
serves as benchmark for evolutionary models in the sub-stellar regime.Comment: 13 pages, 11 figures, 4 tables, submitted to AAS Journal
Three Small Planets Transiting a Hyades Star
We present the discovery of three small planets transiting K2-136 (LP 358
348, EPIC 247589423), a late K dwarf in the Hyades. The planets have orbital
periods of , , and
days, and radii of , , and , respectively. With an age of
600-800 Myr, these planets are some of the smallest and youngest transiting
planets known. Due to the relatively bright (J=9.1) host star, the planets are
compelling targets for future characterization via radial velocity mass
measurements and transmission spectroscopy. As the first known star with
multiple transiting planets in a cluster, the system should be helpful for
testing theories of planet formation and migration.Comment: Accepted to The Astronomical Journa
Exoplanets around Low-mass Stars Unveiled by K2
We present the detection and follow-up observations of planetary candidates
around low-mass stars observed by the K2 mission. Based on light-curve
analysis, adaptive-optics imaging, and optical spectroscopy at low and high
resolution (including radial velocity measurements), we validate 16 planets
around 12 low-mass stars observed during K2 campaigns 5-10. Among the 16
planets, 12 are newly validated, with orbital periods ranging from 0.96-33
days. For one of the planets (K2-151b) we present ground-based transit
photometry, allowing us to refine the ephemerides. Combining our K2 M-dwarf
planets together with the validated or confirmed planets found previously, we
investigate the dependence of planet radius on stellar insolation and
metallicity [Fe/H]. We confirm that for periods days, planets
with a radius are less common than planets with a
radius between 1-2. We also see a hint of the "radius valley"
between 1.5 and 2 that has been seen for close-in planets around
FGK stars. These features in the radius/period distribution could be attributed
to photoevaporation of planetary envelopes by high-energy photons from the host
star, as they have for FGK stars. For the M dwarfs, though, the features are
not as well defined, and we cannot rule out other explanations such as
atmospheric loss from internal planetary heat sources, or truncation of the
protoplanetary disk. There also appears to be a relation between planet size
and metallicity: those few planets larger than about 3 are found
around the most metal-rich M dwarfs.Comment: 29 pages, 21 figures, 6 tables, Accepted in Astronomical Journa
The transiting multi-planet system HD3167: a 5.7 MEarth Super-Earth and a 8.3 MEarth mini-Neptune
HD3167 is a bright (V=8.9 mag) K0V star observed by the NASA's K2 space
mission during its Campaign 8. It has been recently found to host two small
transiting planets, namely, HD3167b, an ultra short period (0.96 d)
super-Earth, and HD3167c, a mini-Neptune on a relatively long-period orbit
(29.85 d). Here we present an intensive radial velocity follow-up of HD3167
performed with the FIES@NOT, [email protected], and HARPS-N@TNG spectrographs. We
revise the system parameters and determine radii, masses, and densities of the
two transiting planets by combining the K2 photometry with our spectroscopic
data. With a mass of 5.69+/-0.44 MEarth, radius of 1.574+/-0.054 REarth, and
mean density of 8.00(+1.0)(-0.98) g/cm^3, HD3167b joins the small group of
ultra-short period planets known to have a rocky terrestrial composition.
HD3167c has a mass of 8.33 (+1.79)(-1.85) MEarth and a radius of
2.740(+0.106)(-0.100) REarth, yielding a mean density of 2.21(+0.56)(-0.53)
g/cm^3, indicative of a planet with a composition comprising a solid core
surrounded by a thick atmospheric envelope. The rather large pressure scale
height (about 350 km) and the brightness of the host star make HD3167c an ideal
target for atmospheric characterization via transmission spectroscopy across a
broad range of wavelengths. We found evidence of additional signals in the
radial velocity measurements but the currently available data set does not
allow us to draw any firm conclusion on the origin of the observed variation.Comment: 18 pages, 11 figures, 5 table
K2-60b and K2-107b. A Sub-Jovian and a Jovian Planet from the K2 Mission
We report the characterization and independent detection of K2-60b, as well as the detection and characterization of K2-107b, two transiting hot gaseous planets from the K2 space mission. We confirm the planetary nature of the two systems and determine their fundamental parameters combining the K2 time-series data with FIES @ NOT and HARPS-N @ TNG spectroscopic observations. K2-60b has a radius of 0.683 +/- 0.037 R-Jup and a mass of 0.426 +/- 0.037 M-Jup and orbits a G4 V star with an orbital period of 3.00267 +/- 0.00006 days. K2-107b has a radius of 1.44 +/- 0.15 R-Jup and a mass of 0.84 +/- 0.08 M-Jup and orbits an F9 IV star every 3.31392 +/- 0.00002 days. K2-60b is among the few planets at the edge of the so-called desert of short-period sub-Jovian planets. K2107b is a highly inflated Jovian planet orbiting an evolved star about to leave the main sequence
PI3Kγ is a molecular switch that controls immune suppression
Macrophages play critical, but opposite, roles in acute and chronic inflammation and cancer1,2,3,4,5. In response to pathogens or injury, inflammatory macrophages express cytokines that stimulate cytotoxic T cells, whereas macrophages in neoplastic and parasitic diseases express anti-inflammatory cytokines that induce immune suppression and may promote resistance to T cell checkpoint inhibitors1,2,3,4,5,6,7. Here we show that macrophage PI 3-kinase γ controls a critical switch between immune stimulation and suppression during inflammation and cancer. PI3Kγ signalling through Akt and mTor inhibits NFκB activation while stimulating C/EBPβ activation, thereby inducing a transcriptional program that promotes immune suppression during inflammation and tumour growth. By contrast, selective inactivation of macrophage PI3Kγ stimulates and prolongs NFκB activation and inhibits C/EBPβ activation, thus promoting an immunostimulatory transcriptional program that restores CD8+ T cell activation and cytotoxicity. PI3Kγ synergizes with checkpoint inhibitor therapy to promote tumour regression and increased survival in mouse models of cancer. In addition, PI3Kγ-directed, anti-inflammatory gene expression can predict survival probability in cancer patients. Our work thus demonstrates that therapeutic targeting of intracellular signalling pathways that regulate the switch between macrophage polarization states can control immune suppression in cancer and other disorders
The Transiting Multi-planet System HD15337: Two Nearly Equal-mass Planets Straddling the Radius Gap
We report the discovery of a super-Earth and a sub-Neptune transiting the star HD 15337 (TOI-402, TIC 120896927), a bright (V = 9) K1 dwarf observed by the Transiting Exoplanet Survey Satellite (TESS) in Sectors 3 and 4. We combine the TESS photometry with archival High Accuracy Radial velocity Planet Searcher spectra to confirm the planetary nature of the transit signals and derive the masses of the two transiting planets. With an orbital period of 4.8 days, a mass of and a radius of 1.64 ± 0.06 R ⊕, HD 15337 b joins the growing group of short-period super-Earths known to have a rocky terrestrial composition. The sub-Neptune HD 15337 c has an orbital period of 17.2 days, a mass of , and a radius of 2.39 ± 0.12 R ⊕, suggesting that the planet might be surrounded by a thick atmospheric envelope. The two planets have similar masses and lie on opposite sides of the radius gap, and are thus an excellent testbed for planet formation and evolution theories. Assuming that HD 15337 c hosts a hydrogen-dominated envelope, we employ a recently developed planet atmospheric evolution algorithm in a Bayesian framework to estimate the history of the high-energy (extreme ultraviolet and X-ray) emission of the host star. We find that at an age of 150 Myr, the star possessed on average between 3.7 and 127 times the high-energy luminosity of the current Sun
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