23 research outputs found
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Vitiligo-like lesions located over In-transit metastases of malignant melanoma as a clinical marker of complete response to pembrolizumab.
Anti-programmed cell death (PD)-1 therapies in metastatic tumors have a high incidence of immune adverse events, including cutaneous manifestations such as vitiligo-like lesions. This side effect is associated with increased survival and it is a clinical marker of response to treatment. This case report is a graphic representation of the appearance of vitiligo-like lesions over in-transit metastases of malignant melanoma linked to a complete response to treatment with pembrolizumab
Tracing kinematical and physical asymmetries in the jet from DG Tau B
Stellar jets can be highly asymmetric and have multiple velocity components.
To clarify the origin of jet asymmetries and constrain their launch mechanism
we study the physical and kinematical structure of the flow emitted by DG Tau
B. The analysis of deep spectra taken at the KECK telescope allows us to infer
the physical properties (the electron and total density, ne and nh, the
ionisation fraction, xe, and the temperature, te) and the spatial distribution
of the velocity components in the two jet lobes. The presence of dust grains in
the jet is investigated by estimating the gas-phase abundance of calcium with
respect to its solar value. At the base of the jet the lines are broad (~100
km/s) and up to three velocity components are detected. At 5" from the source,
however, only the denser and more excited high velocity components survive and
the lines are narrower (~10-30 km/s). The jet is strongly asymmetric both in
velocity and in its physical structure. The red lobe, slower (~140 km/s) and
more collimated, presents low ionisation fractions (xe~0.1-0.4) and
temperatures (te<5e3 K), while the total density is up to ~2.5e4 ccm. The blue
lobe, faster (~-320 km/s) and less collimated, is also less dense (nh~1e4 ccm)
but highly excited (te up to ~5e4 K and xe up to 0.9). The estimated mass loss
rate is similar in the two lobes (~6-8e-9 Msol/yr), suggesting that the
ejection power is comparable on the two sides of the system, as expected from a
magneto-centrifugal ejection mechanism, and that the observed asymmetries are
due to different mass load and propagation properties in an inhomogeneous
environment. Calcium is strongly depleted, indicating that the jet contains
dust grains and, therefore, should originate from a region of the disk
extending beyond the dust sublimation radius. The depletion is lower for higher
velocities, consistent with dust destruction by shocks.Comment: 14 pages, 9 figures, accepted by A&
Metallicity of low-mass stars in Orion
Determining the metal content of low-mass members of young associations
provides a tool that addresses different issues, such as triggered star
formation or the link between the metal-rich nature of planet-host stars and
the early phases of planet formation. The Orion complex is a well known example
of possible triggered star formation and is known to host a rich variety of
proto-planetary disks around its low-mass stars. Available metallicity
measurements yield discrepant results. We analyzed FLAMES/UVES and Giraffe
spectra of low-mass members of three groups/clusters belonging to the Orion
association. Our goal is the homogeneous determination of the metallicity of
the sample stars, which allows us to look for [Fe/H] differences between the
three regions and for the possible presence of metal-rich stars. Nine members
of the ONC and one star each in the Ori cluster and OB1b subgroup
were analyzed. After the veiling determination, we retrieved the metallicity by
means of equivalent widths and/or spectral synthesis using MOOG. We obtain an
average metallicity for the ONC [Fe/H]=-0.01\pm 0.04. No metal-rich stars were
detected and the dispersion within our sample is consistent with measurement
uncertainties. The metallicity of the Ori member is also solar, while
the OB1b star has an [Fe/H] significantly below the ONC average. If confirmed
by additional [Fe/H] determinations in the OB1b subgroup, this result would
support the triggered star formation and the self-enrichment scenario for the
Orion complex.Comment: 13 pages, accepted for publication in A&
Photometric determination of the mass accretion rates of pre-main sequence stars. III. Results in the Large Magellanic Cloud
We present a multi-wavelength study of three star forming regions, spanning
the age range 1-14 Myr, located between the 30 Doradus complex and supernova
SN1987A in the Large Magellanic Cloud (LMC). We reliably identify about 1000
pre-main sequence (PMS) star candidates actively undergoing mass accretion and
estimate their stellar properties and mass accretion rate (Macc). Our
measurements represent the largest Macc dataset of low-metallicity stars
presented so far. As such, they offer a unique opportunity to study on a
statistical basis the mass accretion process in the LMC and, more in general,
the evolution of the mass accretion process around low-metallicity stars. We
find that the typical \dot{M} of PMS stars in the LMC is higher than for
galactic PMS stars of the same mass, independently of their age. Taking into
account the caveats of isochronal age and \dot{M} estimates, the difference in
Macc between the LMC and our Galaxy appears to be about an order of magnitude.
We review the main mechanisms of disk dispersal and find indications that
typically higher Macc are to be expected in low-metallicity environments.
However, many issues of this scenario need to be clarified by future
observations and modeling. We also find that, in the mass range 1-2 M_sun, the
Macc of PMS stars in the LMC increases with stellar mass as
\dot{M}acc\proptoM^b, with b \approx1, i.e. slower than the second power low
found for galactic PMS stars in the same mass regime.Comment: 21 pages, 10 figures, 5 tables; MNRAS 201
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Nivolumab-associated Stevens-Johnson syndrome in a patient with lung cancer
Nivolumab is a fully human immunoglobulin G4 immune checkpoint inhibitor antibody approved for use in the treatment of several malignancies such as lung cancer. Cutaneous reactions to checkpoint inhibitors are frequent, appearing in approximately 40% of patients. Although most of the reactions are well tolerated, these drugs can lead to severe cutaneous adverse reactions, but a quick recognition of the symptoms can significantly decrease their mortality. In this case report, we describe a patient with metastatic squamous lung cell carcinoma suffering from nivolumab-induced Stevens-Johnson syndrome with severe skin denudation and mucosal involvement
Recommended from our members
Vitiligo-like lesions located over In-transit metastases of malignant melanoma as a clinical marker of complete response to pembrolizumab.
Anti-programmed cell death (PD)-1 therapies in metastatic tumors have a high incidence of immune adverse events, including cutaneous manifestations such as vitiligo-like lesions. This side effect is associated with increased survival and it is a clinical marker of response to treatment. This case report is a graphic representation of the appearance of vitiligo-like lesions over in-transit metastases of malignant melanoma linked to a complete response to treatment with pembrolizumab
Hidrocistoma apocrino asociado con tofo gotoso en pabellĂłn auricular.
Apocrine hidrocystomas, also known as apocrine cystadenomas, are bening cystic tumours derived from the secretory portion of apocrine sweat glands.info:eu-repo/semantics/publishe