3,082 research outputs found
Super star cluster feedback driving ionization, shocks and outflows in the halo of the nearby starburst ESO 338-IG04
Stellar feedback strongly affects the interstellar medium (ISM) of galaxies.
Stellar feedback in the first galaxies likely plays a major role in enabling
the escape of LyC photons, which contribute to the re-ionization of the
Universe. Nearby starburst galaxies serve as local analogues allowing for a
spatially resolved assessment of the feedback processes in these galaxies. We
characterize the feedback effects from the star clusters in the local
high-redshift analogue ESO 338-IG04 on the ISM and compare the results with the
properties of the most massive clusters. We use high quality VLT/MUSE optical
integral field data to derive the physical properties of the ISM such as
ionization, density, shocks, and perform new fitting of the spectral energy
distributions of the brightest clusters in ESO 338-IG04 from HST imaging. ESO
338-IG04 has a large ionized halo which we detect to a distance of 9 kpc. We
identify 4 Wolf-Rayet (WR) clusters based on the blue and red WR bump. We
follow previously identified ionization cones and find that the ionization of
the halo increases with distance. Analysis of the galaxy kinematics shows two
complex outflows driven by the numerous young clusters in the galaxy. We find a
ring of shocked emission traced by an enhanced [OI]/H ratio surrounding
the starburst and at the end of the outflow. Finally we detect nitrogen
enriched gas associated with the outflow, likely caused by the WR stars in the
massive star clusters. Photo-ionization dominates the central starburst and
sets the ionization structure of the entire halo, resulting in a density
bounded halo, facilitating the escape of LyC photons. Outside the central
starburst, shocks triggered by an expanding super bubble become important. The
shocks at the end of the outflow suggest interaction between the hot outflowing
material and the more quiescent halo gas.Comment: Accepted for publication in Astronomy and Astrophysics, 22 pages, 15
figure
The impact of Stellar feedback from velocity-dependent ionised gas maps. -- A MUSE view of Haro 11
We have used the capability of the MUSE instrument to explore the impact of
stellar feedback at large scales in Haro 11, a galaxy under extreme starburst
condition and one of the first galaxies where Lyman continuum (LyC) has been
detected. Using Ha, [OIII] and [OI] emission lines from deep MUSE observations,
we have constructed a sequence of velocity-dependent maps of the Ha emission,
the state of the ionised gas and a tracer of fast shocks. These allowed us to
investigate the ionisation structure of the galaxy in 50 kms^2 bins over a
velocity range of -400 to 350 kms. The ionised gas in Haro 11 is assembled by a
rich arrangement of structures, such as superbubbles, filaments, arcs and
galactic ionised channels, whose appearances change drastically with velocity.
The central star forming knots and the star forming dusty arm are the main
engines that power the strong mechanical feedback in this galaxy, although with
different impact on the ionisation structure. Haro 11 appears to leak LyC
radiation in many directions. We found evidence of a kpc-scale fragmented
superbubble, that may have cleared galactic-scale channels in the ISM.
Additionally, the southwestern hemisphere is highly ionised in all velocities,
hinting at a density bound scenario. A compact kpc-scale structure of lowly
ionised gas coincides with the diffuse Lya emission and the presence of fast
shocks. Finally, we find evidence that a significant fraction of the ionised
gas mass may escape the gravitational potential of the galaxy.Comment: Pubisched version. Ionisation values were corrected after discovering
a bug in a code used to generate the map
Spin and lattice excitations of a BiFeO3 thin film and ceramics
We present a comprehensive study of polar and magnetic excitations in BiFeO3
ceramics and a thin film epitaxially grown on an orthorhombic (110) TbScO3
substrate. Infrared reflectivity spectroscopy was performed at temperatures
from 5 to 900 K for the ceramics and below room temperature for the thin film.
All 13 polar phonons allowed by the factor-group analysis were observed in
theceramic samples. The thin-film spectra revealed 12 phonon modes only and an
additional weak excitation, probably of spin origin. On heating towards the
ferroelectric phase transition near 1100 K, some phonons soften, leading to an
increase in the static permittivity. In the ceramics, terahertz transmission
spectra show five low-energy magnetic excitations including two which were not
previously known to be infrared active; at 5 K, their frequencies are 53 and 56
cm-1. Heating induces softening of all magnetic modes. At a temperature of 5 K,
applying an external magnetic field of up to 7 T irreversibly alters the
intensities of some of these modes. The frequencies of the observed spin
excitations provide support for the recently developed complex model of
magnetic interactions in BiFeO3 (R.S. Fishman, Phys. Rev. B 87, 224419 (2013)).
The simultaneous infrared and Raman activity of the spin excitations is
consistent with their assignment to electromagnons
Evolution of magnetic phases and orbital occupation in (SrMnO3)n/(LaMnO3)2n superlattices
The magnetic and electronic modifications induced at the interfaces in
(SrMnO)/(LaMnO) superlattices have been investigated
by linear and circular magnetic dichroism in the Mn L x-ray absorption
spectra. Together with theoretical calculations, our data demonstrate that the
charge redistribution across interfaces favors in-plane ferromagnetic (FM)
order and orbital occupation, in agreement with the
average strain. Far from interfaces, inside LaMnO, electron localization
and local strain favor antiferromagnetism (AFM) and
orbital occupation. For the high density of interfacial planes ultimately
leads to dominant FM order forcing the residual AFM phase to be in-plane too,
while for the FM layers are separated by AFM regions having
out-of-plane spin orientation.Comment: accepted for publication as a Rapid Communication in Physical Review
Systematization of tensor mesons and the determination of the glueball
It is shown that new data on the -resonances in the mass
range MeV support the linearity of the -trajectories,
where is the radial quantum number of quark--antiquark state. In this way
all vacancies for the isoscalar tensor -mesons in the range up to 2450
MeV are filled in. This allows one to fix the broad -state with
MeV and MeV as the lowest tensor glueball. PACS
numbers: 14.40.-n, 12.38.-t, 12.39.-MkComment: 10 pages, 1 figur
Measles among healthcare workers in Italy. Is it time to act?
Vaccination of healthcare workers (HCWs) against measles is strongly recommended in Europe. In this study, we examined the impact of measles on Italian HCWs by systematically and quantitatively analyzing measles cases involving HCWs over time and by identifying the epidemiological characteristics of the respective measles outbreaks. We retrieved data on measles cases from the Italian national integrated measles and rubella surveillance system from January 2013 to May 2019. Additionally, we performed a systematic review of the literature and an analysis of the measles and rubella aggregate outbreaks reporting forms from 2014 to 2018. Our review suggests that preventing measles infection among HCWs in disease outbreaks may be crucial for the elimination of measles in Italy. National policies aiming to increase HCW immunization rates are fundamental to the protection of HCWs and patients, will limit the economic impact of outbreaks on the institutions affected and will help achieve the elimination goal
Safety and activity of trastuzumab-containing therapies for the treatment of metastatic breast cancer: our long-term clinical experience (GOIM study).
Background: Trastuzumab is widely used as the treatment of choice for HER2-positive metastatic breast cancer
(MBC).
Patients and methods: Seventy patients, median age 57 years and range 31–81 years, were included in our
retrospective analysis with the aim to evaluate safety and activity of trastuzumab-containing therapies.
Results: We observed for first-line treatment response rate (RR) 41%, stable disease (SD) 47% and time to
progression (TTP) 8 months (range 1–44). Corresponding numbers for second line were RR 23%, SD 62% and (TTP) 9
months (range 3–23) and beyond second line RR 22%, SD 78% and (TTP) 9 months (range 4–19). Overall survival was
19.2 months (3–62 months). The median cumulative dose of trastuzumab administrated was 5286 mg
(464–17 940 mg). Trastuzumab was well tolerated. Median left ventricular ejection function (LVEF) at baseline was
62% and at the end of treatment was 59%. The more relevant adverse events consisted of an asymptomatic
decrease in LVEF to 40% (baseline 60%) and a grade 3 symptomatic increase in bilirubin.
Conclusion: Trastuzumab-containing therapies in MBC show a good safety and toxicity profile and a remarkable
activity even in heavily pretreated women. Patients should benefit from continued trastuzumab therapy, as shown
by the maintenance of (TTP) even beyond second-line treatment
Symbols of One-Loop Integrals From Mixed Tate Motives
We use a result on mixed Tate motives due to Goncharov
(arXiv:alg-geom/9601021) to show that the symbol of an arbitrary one-loop
2m-gon integral in 2m dimensions may be read off directly from its Feynman
parameterization. The algorithm proceeds via recursion in m seeded by the
well-known box integrals in four dimensions. As a simple application of this
method we write down the symbol of a three-mass hexagon integral in six
dimensions.Comment: 13 pages, v2: minor typos correcte
Gemcitabine-based doublets versus single-agent therapy for elderly patients with advanced nonsmall cell lung cancer: a Literature-based Meta-analysis.
Although platinum-based combinations are considered the best option of care for patients
with advanced nonsmall cell lung cancer (NSCLC), single-agent therapy is the preferred treatment for older
patients. Since the late 1990s, various combinations of third-generation agents (gemcitabine [G], vinorel-
bine, docetaxel, and paclitaxel) have been tested, yielding contradictory results. The authors of this report
performed a literature-based meta-analysis to assess the efficacy and tolerability of G-based doublets
compared with single-agent chemotherapy for elderly patients with NSCLC.
METHODS: Data from all published, randomized, phase 3 trials that compared a G-based doublet with a third-generation single agent in elderly patients were collected from electronic databases (Medline and the Cochrane Central Register of Controlled Trials), relevant reference lists, and abstract books. Pooled odds ratios (ORs) were calculated for the 1-year survival rate, the overall response rate (ORR), and grade 3 and 4 toxicities. RESULTS: Four eligible trials (1436 patients) were selected from 442 studies that initially were identified. A significant difference in ORR favoring G-based doublets over single agents was observed (OR, 0.65; 95% confidence interval [95% CI], 0.51-0.82 [P<.001]), whereas the trend toward an improved 1-year survival rate was not significant (OR, 0.78; 95% CI, 0.57-1.06 [P¼.169]). Grade 3 and 4 toxicities did not differ significantly except for thrombocytopenia (OR, 1.76; 95% CI, 1.12-2.76 [P¼.014]).
CONCLUSIONS: G-based doublets appeared to be effective and feasible compared with single agents in the treatment of elderly patients with advanced NSCLC who were not suitable for full-dose, platinum-based chemotherapy. Further prospective, elderly specific, phase 3 trials will be necessary
The Risk of Toxicities from Trastuzumab, Alone or in Combination, in an Elderly Breast Cancer Population
Abstract
Background: Breast cancer in the elderly is associated with
high recurrence and death rates, due mostly to undertreatment.
Human epidermal growth factor receptor type 2
(HER2) overexpression is infrequent in older patients. Trastuzumab-
based chemotherapy is often withheld from elderly
patients because of its cardiotoxicity. Patients and Methods:
Medical records of consecutive HER2-positive breast
cancer patients aged 65 70 years old treated between 2005
and 2010 in the participating centers were retrospectively
reviewed. All patients underwent multidimensional geriatric
assessment (MGA). Results: Among 59 patients identified,
51 patients were evaluable (median age 76 years). The rate
of any adverse event was 20% (10/51). The most relevant cardiac
adverse event consisted of symptomatic congestive
heart failure (CHF; n = 1, 2%) followed by asymptomatic decreases
of left ventricular ejection fraction (LVEF; n = 6, 12%).
Other toxicities included moderate hypersensitivity reactions during trastuzumab infusions (n = 3, 6%). Hypertension,
obesity, prior anthracyclines exposure and concurrent
chemotherapy were associated with a higher incidence of
toxic events. Previous radiotherapy, concurrent endocrine
therapy and different trastuzumab-based regimens did not
seem to influence toxicity. Conclusions: Our data suggest
that trastuzumab has a good safety profile in nonfrail women
aged 70 years and older. These favorable findings may be
related to a limited number of anthracycline pretreatments,
patient selection and a close cardiologic monitoring
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