Neutron-star mergers were recently confirmed as sites of rapid-neutron-capture (r-process) nucleosynthesis1-3. However, in Galactic chemical evolution models, neutron-star mergers alone cannot ...reproduce the observed element abundance patterns of extremely metal-poor stars, which indicates the existence of other sites of r-process nucleosynthesis4-6. These sites may be investigated by studying the element abundance patterns of chemically primitive stars in the halo of the Milky Way, because these objects retain the nucleosynthetic signatures of the earliest generation of stars7-13. Here we report the element abundance pattern ofthe extremely metal-poor star SMSS J200322.54-114203.3. We observe a large enhancement in r-process elements, with very low overall metallicity. The element abundance pattern is well matched by the yields of a single 25-solar-mass magnetorotational hypernova. Such a hypernova could produce not only the r-process elements, but also light elements during stellar evolution, and iron-peak elements during explosive nuclear burning. Hypernovae are often associated with long-duration y-ray bursts in the nearby Universe8. This connection indicates that similar explosions of fast-spinning strongly magnetized stars occurred during the earliest epochs of star formation in our Galaxy.
Managing menopausal symptoms after cancer Szabo, R. A.; Marino, J. L.; Hickey, M.
Climacteric : the journal of the International Menopause Society,
11/2019, Letnik:
22, Številka:
6
Journal Article
Recenzirano
The joint burden of cancer and menopause impacts millions of women globally. This review provides an approach to management of menopausal symptoms after cancer in all settings. This includes an ...overview of current evidence for both hormonal and non-hormonal treatments for vasomotor symptoms and vaginal dryness after cancer. Systemic menopausal hormone therapy provides symptom control and may be used after most cancers but should be avoided after estrogen receptor-positive breast cancer and after some other estrogen-dependent cancers. Non-hormonal therapies have been minimally studied in women after a cancer diagnosis and, where they have been studied, it is usually in women with breast cancer. Non-hormonal methods to manage vasomotor symptoms include cognitive behavioral therapy, hypnosis, selective serotonin reuptake inhibitors, serotonin noradrenaline reuptake inhibitors, clonidine, and gabapentin. Vaginal estrogen may be useful to address vaginal dryness. However, safety data in breast cancer patients are still lacking and there is currently no consensus. Lubricants may also help with pain with sexual activity. Management of menopausal symptoms after cancer may be challenging and should include information about induced menopause and possible symptoms as well as available treatments. Management then requires a holistic and multidisciplinary approach with individualized care.
Retrospective, longitudinal analysis of motor recovery data from individuals with cervical (C4-C7) sensorimotor complete spinal cord injury (SCI) according to the International Standards for ...Neurological Classification of Spinal Cord Injury (ISNCSCI).
To analyze the extent and patterns of spontaneous motor recovery over the first year after traumatic cervical sensorimotor complete SCI.
Datasets from the European multicenter study about SCI (EMSCI) and the Sygen randomized clinical trial were examined for conversion of American Spinal Injury Association (ASIA) Impairment Scale (AIS) grade, change in upper extremity motor score (UEMS) or motor level, as well as relationships between these measures.
There were no overall differences between the EMSCI and Sygen datasets in motor recovery patterns. After 1 year, up to 70% of subjects spontaneously recovered at least one motor level, but only 30% recovered two or more motor levels, with lesser values at intermediate time points. AIS grade conversion did not significantly influence motor level changes. At 1 year, the average spontaneous improvement in bilateral UEMS was 10-11 motor points. There was only moderate relationship between a change in UEMS and a change in cervical motor level (r(2)=0.30, P<0.05). Regardless of initial cervical motor level, most individuals recover a similar number of motor points or motor levels.
Careful tracking of cervical motor recovery outcomes may provide the necessary sensitivity and accuracy to reliably detect a subtle, but meaningful treatment effect after sensorimotor complete cervical SCI. The distribution of the UEMS change may be more important functionally than the total UEMS recovered.
We measured the gas abundance profiles in a sample of 122 face-on spiral galaxies observed by the CALIFA survey and included all spaxels whose line emission was consistent with star formation. This ...type of analysis allowed us to improve the statistics with respect to previous studies, and to properly estimate the oxygen distribution across the entire disc to a distance of up to 3−4 disc effective radii (re). We confirm the results obtained from classical H ii region analysis. In addition to the general negative gradient, an outer flattening can be observed in the oxygen abundance radial profile. An inner drop is also found in some cases. There is a common abundance gradient between 0.5 and 2.0 re of αO / H = − 0.075 dex /re with a scatter of σ = 0.016 dex /re when normalising the distances to the disc effective radius. By performing a set of Kolmogorov-Smirnov tests, we determined that this slope is independent of other galaxy properties, such as morphology, absolute magnitude, and the presence or absence of bars. In particular, barred galaxies do not seem to display shallower gradients, as predicted by numerical simulations. Interestingly, we find that most of thegalaxies in the sample with reliable oxygen abundance values beyond ~2 effective radii (57 galaxies) present a flattening of the abundance gradient in these outer regions. This flattening is not associated with any morphological feature, which suggests that it is a common property of disc galaxies. Finally, we detect a drop or truncation of the abundance in the inner regions of 27 galaxies in the sample; this is only visible for the most massive galaxies.
We present the largest and most homogeneous catalog of H ii regions and associations compiled so far. The catalog comprises more than 7000 ionized regions, extracted from 306 galaxies observed by the ...CALIFA survey. We describe the procedures used to detect, select, and analyze the spectroscopic properties of these ionized regions. In the current study we focus on characterizing of the radial gradient of the oxygen abundance in the ionized gas, based on the study of the deprojecteddistribution of H ii regions. We found that all galaxies without clear evidence of an interaction present a common gradient in the oxygen abundance, with a characteristic slope of αO/H = −0.1 dex/re between 0.3 and 2 disk effective radii (re), and a scatter compatible with random fluctuations around this value, when the gradient is normalized to the disk effective radius. The slope is independent of morphology, the incidence of bars, absolute magnitude, or mass. Only those galaxies with evidence of interactions and/or clear merging systems present a significantly shallower gradient, consistent with previous results. The majority of the 94 galaxies with H ii regions detected beyond two disk effective radii present a flattening in the oxygen abundance. The flattening is statistically significant. We cannot provide a conclusive answer regarding the origin of this flattening. However, our results indicate that its origin is most probably related to the secular evolution of galaxies. Finally, we find a drop/truncation of the oxygen abundance in the inner regions for 26 of the galaxies. All of them are non-interacting, mostly unbarred Sb/Sbc galaxies. This feature is associated with a central star-forming ring, which suggests that both features are produced by radial gas flows induced by resonance processes. Our result suggests that galaxy disks grow inside-out, with metal enrichment driven by the local star formation history and with a small variation galaxy-by-galaxy. At a certain galactocentric distance, the oxygen abundance seems to be correlated well with the stellar mass density and total stellar mass of the galaxies, independently of other properties of the galaxies. Other processes, such as radial mixing and inflows/outflows seem to have a limited effect on shaping of the radial distribution of oxygen abundances, although they are not ruled out.
ABSTRACT The "main sequence of galaxies"-defined in terms of the total star formation rate versus the total stellar mass M*-is a well-studied tight relation that has been observed at several ...wavelengths and at different redshifts. All earlier studies have derived this relation from integrated properties of galaxies. We recover the same relation from an analysis of spatially resolved properties, with integral field spectroscopic (IFS) observations of 306 galaxies from the CALIFA survey. We consider the SFR surface density in units of log(M yr−1 Kpc−2) and the stellar mass surface density in units of log(M Kpc−2) in individual spaxels that probe spatial scales of 0.5-1.5 Kpc. This local relation exhibits a high degree of correlation with small scatter ( = 0.23 dex), irrespective of the dominant ionization source of the host galaxy or its integrated stellar mass. We highlight (i) the integrated star formation main sequence formed by galaxies whose dominant ionization process is related to star formation, for which we find a slope of 0.81 0.02; (ii) for the spatially resolved relation obtained with the spaxel analysis, we find a slope of 0.72 0.04; and (iii) for the integrated main sequence, we also identified a sequence formed by galaxies that are dominated by an old stellar population, which we have called the retired galaxies sequence.
ABSTRACT
In this work, we combine spectroscopic information from the SkyMapper survey for Extremely Metal-Poor stars and astrometry from Gaia DR2 to investigate the kinematics of a sample of 475 ...stars with a metallicity range of $-6.5 \le \rm Fe/H \le -2.05$ dex. Exploiting the action map, we identify 16 and 40 stars dynamically consistent with the Gaia Sausage and Gaia Sequoia accretion events, respectively. The most metal poor of these candidates have metallicities of $\rm Fe/H=-3.31\, \mathrm{ and }\, -3.74$, respectively, helping to define the low-metallicity tail of the progenitors involved in the accretion events. We also find, consistent with other studies, that ∼21 per cent of the sample have orbits that remain confined to within 3 kpc of the Galactic plane, that is, |Zmax| ≤ 3 kpc. Of particular interest is a subsample (∼11 per cent of the total) of low |Zmax| stars with low eccentricities and prograde motions. The lowest metallicity of these stars has Fe/H = –4.30 and the subsample is best interpreted as the very low-metallicity tail of the metal-weak thick disc population. The low |Zmax|, low eccentricity stars with retrograde orbits are likely accreted, while the low |Zmax|, high eccentricity pro- and retrograde stars are plausibly associated with the Gaia Sausage system. We find that a small fraction of our sample (∼4 per cent of the total) is likely escaping from the Galaxy, and postulate that these stars have gained energy from gravitational interactions that occur when infalling dwarf galaxies are tidally disrupted.
We report the discovery of a 104 kpc2 gaseous structure detected in O iiλλ3727, 3729 in an over-dense region of the COSMOS-Gr30 galaxy group at z ~ 0.725 with deep MUSE Guaranteed Time Observations. ...We estimate the total amount of diffuse ionised gas to be of the order of (~5 ± 3) × 1010 M⊙ and explore its physical properties to understand its origin and the source(s) of the ionisation. The MUSE data allow the identification of a dozen group members that are embedded in this structure through emission and absorption lines. We extracted spectra from small apertures defined for both the diffuse ionised gas and the galaxies. We investigated the kinematics and ionisation properties of the various galaxies and extended gas regions through line diagnostics (R23, O32, and O iii/Hβ) that are available within the MUSE wavelength range. We compared these diagnostics to photo-ionisation models and shock models. The structure is divided into two kinematically distinct sub-structures. The most extended sub-structure of ionised gas is likely rotating around a massive galaxy and displays filamentary patterns that link some galaxies. The second sub-structure links another massive galaxy that hosts an active galactic nucleus (AGN) to a low-mass galaxy, but it also extends orthogonally to the AGN host disc over ~ 35 kpc. This extent is likely ionised by the AGN itself. The location of small diffuse regions in the R23 vs. O32 diagram is compatible with photo-ionisation. However, the location of three of these regions in this diagram (low O32, high R23) can also be explained by shocks, which is supported by their high velocity dispersions. One edge-on galaxy shares the same properties and may be a source of shocks. Regardless of the hypothesis, the extended gas seems to be non-primordial. We favour a scenario where the gas has been extracted from galaxies by tidal forces and AGN triggered by interactions between at least the two sub-structures.
Abstract
We present a galaxy classification system for 238 (E1–Sdm) CALIFA (Calar Alto Legacy Integral Field Area) galaxies based on the shapes and amplitudes of their circular velocity curves ...(CVCs). We infer the CVCs from the de-projected surface brightness of the galaxies, after scaling by a constant mass-to-light ratio based on stellar dynamics – solving axisymmetric Jeans equations via fitting the second velocity moment
$V_{\mathrm{rms}}=\sqrt{V^2+\sigma ^2}$
of the stellar kinematics. We use principal component analysis (PCA) applied to the CVC shapes to find characteristic features and use a k-means classifier to separate circular curves into classes. This objective classification method identifies four different classes, which we name slow-rising (SR), flat (FL), round-peaked (RP) and sharp-peaked (SP) circular curves. SR are typical for low-mass, late-type (Sb–Sdm), young, faint, metal-poor and disc-dominated galaxies. SP are typical for high-mass, early-type (E1–E7), old, bright, metal-rich and bulge-dominated galaxies. FL and RP appear presented by galaxies with intermediate mass, age, luminosity, metallicity, bulge-to-disc ratio and morphologies (E4–S0a, Sa–Sbc). The discrepancy mass factor, f
d = 1 − M
*/M
dyn, have the largest value for SR and SP classes (∼ 74 per cent and ∼ 71 per cent, respectively) in contrast to the FL and RP classes (with ∼ 59 per cent and ∼ 61 per cent, respectively). Circular curve classification presents an alternative to typical morphological classification and appears more tightly linked to galaxy evolution.
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