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Star formation and stellar feedback are interlinked processes that redistribute energy and matter throughout galaxies. When young, massive stars form in spatially clustered environments, they create pockets of expanding gas termed superbubbles. As these processes play a critical role in shaping galaxy discs and regulating the baryon cycle, measuring the properties of superbubbles provides important input for galaxy evolution models. With wide coverage and high angular resolution (50-150 pc) of the PHANGS-ALMA $^{12}$CO (2-1) survey, we can now resolve and identify a statistically representative number of superbubbles with molecular gas in nearby galaxies. We identify superbubbles by requiring spatial correspondence between shells in CO with stellar populations identified in PHANGS-HST, and combine the properties of the stellar populations with CO to constrain feedback models and quantify their energetics. We visually identify 325 cavities across 18 PHANGS-ALMA galaxies, 88 of which have clear superbubble signatures (unbroken shells, central clusters, kinematic signatures of expansion). We measure their radii and expansion velocities using CO to dynamically derive their ages and the mechanical power driving the bubbles, which we use to compute the expected properties of the parent stellar populations driving the bubbles. We find consistency between the predicted and derived stellar ages and masses of the stellar populations if we use a supernova blast wave model that injects energy with a coupling efficiency of 10%, whereas continuous models fail to explain stellar ages we measure. Not only does this confirm molecular gas accurately traces superbubble properties, but it also provides key observational constraints for superbubble models. We also find evidence that the bubbles sweep up gas as they expand and speculate that these sites have the potential to host new generations of stars., Comment: 21 pages, 15 figures, 3 tables. Accepted to A&A. Abstract abridged for arXiv

There exists some consensus that stellar mass surface density ($Σ_{*}$) and molecular gas mass surface density ($Σ_{\rm mol}$) are the main quantities responsible for locally setting the star formation rate. This regulation is inferred from locally resolved scaling relations between these two quantities and the star formation rate surface density ($Σ_{\rm SFR}$). However, the universality of these relations is debated. Here, we probe the interplay between these three quantities across different galactic environments at a spatial resolution of 150 pc. We perform a hierarchical Bayesian linear regression to find the best set of parameters $C_{*}$, $C_{\rm mol}$, and $C_{\rm norm}$ that describe the star-forming plane conformed by these quantities, such that $\log Σ_{\rm SFR} = C_{*} \log Σ_{*} + C_{\rm mol} \log Σ_{\rm mol} + C_{\rm norm}$, and explore variations in the determined parameters across galactic environments, focusing our analysis on the $C_{*}$ and $C_{\rm mol}$ slopes. We find signs of variations in the posterior distributions of $C_{*}$ and $C_{\rm mol}$ across different galactic environments. Bars show the most negative value of $C_{*}$, a sign of longer depletion times, while spiral arms show the highest $C_{*}$ among all environments. We conclude that systematic variations in the interplay of $Σ_{*}$, $Σ_{\rm mol}$ and $Σ_{\rm SFR}$ across galactic environments exist at a spatial resolution of 150 pc, and we interpret these variations as produced by an additional mechanism regulating the formation of stars that is not captured by either $Σ_{*}$ or $Σ_{\rm mol}$. We find that these variations correlate with changes in the star formation efficiency across environments, which could be linked to the dynamical state of the gas that prevents it from collapsing and forming stars, or to changes in the molecular gas fraction., 21 pages, 16 figures, accepted for publication in A&A

Aims. There exists some consensus that the stellar mass surface density (Σ⋆) and molecular gas mass surface density (Σmol) are the main quantities responsible for locally setting the star formation rate. This regulation is inferred from locally resolved scaling relations between these two quantities and the star formation rate surface density (ΣSFR), which have been extensively studied in a wide variety of works. However, the universality of these relations is debated. Here, we probe the interplay between these three quantities across different galactic environments at a spatial resolution of 150 pc. Methods. We performed a hierarchical Bayesian linear regression to find the best set of parameters C⋆, Cmol, and Cnorm that describe the star-forming plane conformed by Σ⋆, Σmol, and ΣSFR, such that logΣSFR = C⋆logΣ⋆ + CmollogΣmol + Cnorm. We also explored variations in the determined parameters across galactic environments, focusing our analysis on the C⋆ and Cmol slopes. Results. We find signs of variations in the posterior distributions of C⋆ and Cmol across different galactic environments. The dependence of ΣSFR on Σ⋆ spans a wide range of slopes, with negative and positive values, while the dependence of ΣSFR on Σmol is always positive. Bars show the most negative value of C⋆ (−0.41), which is a sign of longer depletion times, while spiral arms show the highest C⋆ among all environments (0.45). Variations in Cmol also exist, although they are more subtle than those found for C⋆. Conclusions. We conclude that systematic variations in the interplay of Σ⋆, Σmol, and ΣSFR across different galactic environments exist at a spatial resolution of 150 pc, and we interpret these variations to be produced by an additional mechanism regulating the formation of stars that is not captured by either Σ⋆ or Σmol. Studying environmental variations in single galaxies, we find that these variations correlate with changes in the star formation efficiency across environments, which could be linked to the dynamical state of the gas that prevents it from collapsing and forming stars, or to changes in the molecular gas fraction.

In order to build more realistic single stellar population (SSP) models with variable alpha-enhancement, we have recently determined [Mg/Fe] in a uniform scale with a precision of about 0.1 dex for 752 stars in the MILES empirical library. The [alpha/Fe] abundance ratio is commonly used as a good temporal scale indicator of star formation, taking Mg as a template for alpha elements. Calcium is another element whose abundance is currently being investigated for the MILES stars. The MILES library is also being expanded by around 20% by including stars with known Teff, log g, [Fe/H] and [Mg/Fe]. The transformation of their photospheric parameters to the MILES system has been carried out, but the calibration of their [Mg/Fe] is still in progress. In parallel, C, N and O abundances are also being compiled from literature for the library stars because they play an important role in the photospheric opacity, particularly influencing the blue spectral region. The Galactic kinematic classification of MILES stars with compiled [Mg/Fe] has been just computed such that this information can be considered in the SSP modeling. Comparisons of theoretical stellar predictions of the Lick line-strength indices against the MILES data have revealed the good behaviour of Fe-sensitive indices predictions, while highlighting areas for improvement in some models for the higher order H-Balmer features., Comment: International Workshop on Stellar Spectral Libraries (Lyon, France, 2013 Oct), to be published in ASI Conference Series, 2014, Vol. 10 (8 pages, 5 figures)

We have fitted the Mg2 absorption index gradients for 21 brightest cluster galaxies (BCGs), in the nearby Universe, for which we have obtained high signal-to-noise ratio, long-slit spectra on the Gemini telescopes. This is a sub-sample of a large optical, spatially-resolved, spectroscopic sample of BCGs which allows possible connections between the kinematical, dynamical and stellar population properties to be studied. We find a weak correlation between the Mg2 gradients and central velocity dispersion, with gradients becoming steeper with increasing mass. An equivalent correlation for normal ellipticals in the same mass range is not found, suggesting that the BCG stellar population profiles are shaped by mechanisms related to the potential well of the cluster where they live. This suggestion is reinforced by the existence of a correlation between the Mg2 gradients and the BCG distance to the X-ray peak luminosity of the cluster., Comment: 9 pages, 6 figures, accepted for publication in MNRAS

We present a comprehensive analysis of the stellar population properties (age, metallicity and the alpha-element enhancement [E/Fe]) and morphologies of red-sequence galaxies in 24 clusters and groups from z~0.75 to z~0.45. The dataset, consisting of 215 spectra drawn from the ESO Distant Cluster Survey, constitutes the largest spectroscopic sample at these redshifts for which such an analysis has been conducted. Analysis reveals that the evolution of the stellar population properties of red-sequence galaxies depend on their mass: while the properties of most massive are well described by passive evolution and high-redshift formation, the less massive galaxies require a more extended star formation history. We show that these scenarios reproduce the index-sigma relations as well as the galaxy colours. The two main results of this work are (1) the evolution of the line-strength indices for the red-sequence galaxies can be reproduced if 40% of the galaxies with sigma < 175 km/s entered the red-sequence between z=0.75 to z=0.45, in agreement with the fraction derived in studies of the luminosity functions, and (2) the percentage the red-sequence galaxies exhibiting early-type morphologies (E and S0) decreases by 20% from z=0.75 to z=0.45. This can be understood if the red-sequence gets populated at later times with disc galaxies whose star formation has been quenched. We conclude that the processes quenching star formation do not necessarily produce a simultaneous morphological transformation of the galaxies entering the red-sequence., Accepted for publication in A&A

Opioid receptors belong to the family of the CTP-binding proteins coupled receptors. In in vitro systems much work has been done to characterize the subtypes of G proteins regulated by opioid receptors. However, to achieve this goal in vivo is a complicated issue. Pioneering studies involving pertussis toxin demonstrated the regulation of G(i)/G(o) to produce supraspinal opioid analgesia. In characterizing those G proteins regulated by mu and delta opioid receptors to induce supraspinal analgesia in the mouse, our group has explored the effectiveness of in vivo administration of antisera raised against different Gα subunits and antisense oligodeoxynucleotides to their mRNAs.

Polyclonal antibodies directed against the amino-terminal portion of the cloned rat μ-opioid receptor (μOR) were raised in rabbits. The antibodies diminished the specific binding of 125I-Tyr27-β-endorphin-(1-31) (human) and [3H][D-Ala2,N-MePhe4,Gly-ol5]enkephalin, but not that of the δOR-selective ligand [3H][D-Pen2,5]enkephalin, to mouse brain membranes. The intracerebroventricular administration to mice of affinity-purified anti- μOR IgGs impaired the antinociception produced by the μOR agonists [D- Ala2,N-MePhe4,Gly-ol5]enkephalin and morphine and the μ/δOR agonists β- endorphin-(1-31) and [D-Ala2,D-Leu5]enkephalin, when studied 24 hr later in the tailimmersion test. Antinociception produced by the δOR-selective agonists [D-Pen2,5]enkephalin and [D-Ala2]deltorphin II was fully displayed in these mice. Immunoblots of sodium dodecyl sulfate-solubilized membranes from mouse central nervous system regions revealed protein bands of M(r) 43,000, 51,000, and 58,000. Also detected were bands of higher molecular weights, 100,000 and 114,000, which probably corresponded to dimeric forms, because they disappeared after sonication of the solubilized tissues. This immunoreactivity was present in regions of mouse central nervous system and was barely detected in NG 108-15 cells. After treatment of the solubilized material with endoglycosidase F, the antibodies labeled a band of M(r) 43,000, coincident with the weight of the cloned μOR. These results confirm the existence of several molecular forms of the μOR due to glycosylation.

Porcine dynorphin B-29 was synthesized by solid phase procedures and purified using gel filtration, ion exchange, reverse phase liquid chromatography and preparative high pressure liquid chromatogrphy (HPLC). Binding experiments using brain tissue indicated this peptide displaced ¿ and k ligands equally well and had significant, though less, affinity for ¿. In isolated tissue systems, its potency ranked as follows: guinea pig ileum, mouse vas, rabbit vas, and rat vas. Interestingly, all IC 50s were reduced in the presence of peptidase inhibitors, particularly in the rabbit vas. These results indicate that dynorphin B-29 like dynorphin, interacts with multiple receptors in the brain, as well as in isolated tissue systems.

The effect of dynorphin was determind on the binding of radioactive ¿, ¿ and k ligands to mouse brain P2 fractions in vitro. The Bmax of high affinity sites of each ligand was lowered and the Kd was raised for k ligands. This suggests that the mode of interaction of dynorphin with brain is complex and may involve a site that allosterically affects the binding sites of other opiates. © 1982.

We discovered a mistake in Eqs. (7) and (10) of Saglia et al. (2010, A&A, 524, A6), which propagates to Tables 8 and 9 and Fig. 25. We revise the tables, the figure and the affected statements in the paper. As a result, the reduction in the luminosity evolution due to the effects of the size and velocity dispersion evolution is smaller than claimed in Saglia et al. (2010).

The Javalambre-Physics of the Accelerated Universe Astrophysical Survey (J-PAS) is a narrow band, very wide field Cosmological Survey to be carried out from the Javalambre Observatory in Spain with a purpose-built, dedicated 2.5m telescope and a 4.7 sq.deg. camera with 1.2Gpix. Starting in late 2015, J-PAS will observe 8500sq.deg. of Northern Sky and measure $0.003(1+z)$ photo-z for $9\times10^7$ LRG and ELG galaxies plus several million QSOs, sampling an effective volume of $\sim 14$ Gpc$^3$ up to $z=1.3$ and becoming the first radial BAO experiment to reach Stage IV. J-PAS will detect $7\times 10^5$ galaxy clusters and groups, setting constrains on Dark Energy which rival those obtained from its BAO measurements. Thanks to the superb characteristics of the site (seeing ~0.7 arcsec), J-PAS is expected to obtain a deep, sub-arcsec image of the Northern sky, which combined with its unique photo-z precision will produce one of the most powerful cosmological lensing surveys before the arrival of Euclid. J-PAS unprecedented spectral time domain information will enable a self-contained SN survey that, without the need for external spectroscopic follow-up, will detect, classify and measure $\sigma_z\sim 0.5\%$ redshifts for $\sim 4000$ SNeIa and $\sim 900$ core-collapse SNe. The key to the J-PAS potential is its innovative approach: a contiguous system of 54 filters with $145\AA$ width, placed $100\AA$ apart over a multi-degree FoV is a powerful "redshift machine", with the survey speed of a 4000 multiplexing low resolution spectrograph, but many times cheaper and much faster to build. The J-PAS camera is equivalent to a 4.7 sq.deg. "IFU" and it will produce a time-resolved, 3D image of the Northern Sky with a very wide range of Astrophysical applications in Galaxy Evolution, the nearby Universe and the study of resolved stellar populations., Comment: 215 pages, 70 figures. J-PAS "Red Book", containing a description of the technical aspects of the Survey and its main scientific goals

Context. The upcoming new generation of optical spectrographs on four-meter-class telescopes, with their huge multiplexing capabilities, excellent spectral resolution, and unprecedented wavelength coverage, will provide invaluable information for reconstructing the history of star formation in individual galaxies up to redshifts of about 0.7. Aims. We aim at defining simple but robust and meaningful physical parameters that can be used to trace the coexistence of widely diverse stellar components: younger stellar populations superimposed on the bulk of older ones. Methods. We produced spectra of galaxies closely mimicking data from the forthcoming Stellar Populations at intermediate redshifts Survey (StePS), a survey that uses the WEAVE spectrograph on the William Herschel Telescope. First, we assessed our ability to reliably measure both ultraviolet and optical spectral indices in galaxies of different spectral types for typically expected signal-to-noise ratios. We then analyzed such mock spectra with a Bayesian approach, deriving the probability density function of r- and u-band light-weighted ages as well as of their difference. Results. We find that the ultraviolet indices significantly narrow the uncertainties in estimating the r- and u-band light-weighted ages and their difference in individual galaxies. These diagnostics, robustly retrievable for large galaxy samples even when observed at moderate signal-to-noise ratios, allow us to identify secondary episodes of star formation up to an age of ∼0.1 Gyr for stellar populations older than ∼1.5 Gyr, pushing up to an age of ∼1 Gyr for stellar populations older than ∼5 Gyr. Conclusions. The difference between r-band and u-band light-weighted ages is shown to be a powerful diagnostic to characterize and constrain extended star-formation histories and the presence of young stellar populations on top of older ones. This parameter can be used to explore the interplay between different galaxy star-formation histories and physical parameters such as galaxy mass, size, morphology, and environment.© ESO 2019., L. C. wish to acknowledge financial support from Premiale 2015 MITiC, program 1.05.06.10 and Comunidad de Madrid under Atraccion de Talento grant 2018-T2/TIC-11612. A. I., S. Z., M. L., A. G., A. M., and C. T. acknowledge the financial support from the INAF PRIN-SKA 2017 program 1.05.01.88.04.ESKAPE-HI. I. L. acknowledges financial support from INAF-WEAVE funds, program 1.05.03.04.05. R. G. B. acknowledges support from the Spanish Ministry of Economy and Competitiveness through grant 205 AYA2016-77846-P and the State Agency for Research of the Spanish MCIU through the >Center of Excellence Severo Ochoa> award to 2017 the Instituto de Astrofisica de Andalucia (SEV-2017-0709). A. F. M. has received financial support through the Postdoctoral Junior Leader Fellowship Programme from >La Caixa> Banking Foundation (LCF/BQ/LI18/11630007). B. V. acknowledges the financial support from INAF Main Stream 2018 (P. I.: B. Vulcani).