The supermassive black hole mass - S\'ersic index relations for bulges and elliptical galaxies

Scaling relations between supermassive black hole mass, M_BH, and host galaxy properties are a powerful instrument for studying their coevolution. A complete picture involving all of the black hole scaling relations, in which each relation is consistent with the others, is necessary to fully understand the black hole-galaxy connection. The relation between M_BH and the central light concentration of the surrounding bulge, quantified by the S\'ersic index n, may be one of the simplest and strongest such relations, requiring only uncalibrated galaxy images. We have conducted a census of literature S\'ersic index measurements for a sample of 54 local galaxies with directly measured M_BH values. We find a clear M_BH - n relation, despite an appreciable level of scatter due to the heterogeneity of the data. Given the current M_BH - L_sph and the L_sph - n relations, we have additionally derived the expected M_BH - n relations, which are marginally consistent at the 2 sigma level with the observed relations. Elliptical galaxies and the bulges of disc galaxies are each expected to follow two distinct bent M_BH - n relations due to the S\'ersic/core-S\'ersic divide. For the same central light concentration, we predict that M_BH in the S\'ersic bulges of disc galaxies are an order magnitude higher than in S\'ersic elliptical galaxies if they follow the same M_BH - L_sph relation.Comment: 12 pages, 6 figures, 5 tables, accepted for publication in MNRA

CD271 downregulation promotes melanoma progression and invasion in 3-dimensional models and in zebrafish

CD271 is a neurotrophin receptor variably expressed in melanoma. While contradictory data are reported on its role as a marker of tumor initiating cells, little is known on its function in tumor progression. CD271 expression was higher in spheroids derived from freshly isolated cells of primary melanomas and in primary WM115 and WM793-B cell lines, while it decreased during progression to advanced stages in cells isolated from metastatic melanomas and in metastatic WM266-4 and 1205Lu cell lines. Moreover, CD271 was scarcely detected in the highly invasive spheroids (SKMEL28 and 1205Lu). CD271, originally expressed in the epidermis of skin reconstructs, disappeared when melanoma started to invade the dermis. SKMEL8 CD271(-) cells showed greater proliferation and invasiveness in vitro, and were associated with a higher number of metastases in zebrafish, as compared to CD271(+) cells. CD271 silencing in WM115 induced a more aggressive phenotype in vitro and in vivo. On the contrary, CD271 overexpression in SKMEL28 cells reduced invasion in vitro, and CD271 overexpressing 1205Lu cells was associated with a lower percentage of metastases in zebrafish. A reduced cell-cell adhesion was also observed in absence of CD271. Taken together, these results indicate that CD271 loss is critical for melanoma progression and metastasis

An energy assessment method for SMEs: case study of an Italian mechanical workshop

Abstract Nowadays, climate change requires companies to reduce their energy consumption and make their production systems more efficient. However, the complexity of the methodologies, the lack of transparency or high efforts (personnel/time) make this challenge especially difficult for SMEs. In this context, the present paper proposes a workflow to supports SMEs in a lean energy analysis. Through the implementation of several methodologies, a comprehensive assessment of energy consumption was carried out. The application to a real case study allowed to identify energy inefficiencies and to evaluate the energy saving and performance improvement actions

a method for lean energy assessment of manufacturing systems

Abstract Manufacturing systems are among the main consumers of energy. Several methods and tools have been developed to support companies toward energy efficiency. However, they generally require high computational effort, onerous measurement campaigns or complex models. In this paper, a method to perform a lean energy assessment starting from the asset characteristics is proposed. It is based on a set of corrective factors that consider both technical and productive aspects. The final goal is to overcome the lack of precise data needed to identify hotspots from the energy point of view. A real industrial case study allows implementing the method and demonstrating its usefulness

A Soluble Phase Field Model

The kinetics of an initially undercooled solid-liquid melt is studied by means of a generalized Phase Field model, which describes the dynamics of an ordering non-conserved field phi (e.g. solid-liquid order parameter) coupled to a conserved field (e.g. thermal field). After obtaining the rules governing the evolution process, by means of analytical arguments, we present a discussion of the asymptotic time-dependent solutions. The full solutions of the exact self-consistent equations for the model are also obtained and compared with computer simulation results. In addition, in order to check the validity of the present model we confronted its predictions against those of the standard Phase field model and found reasonable agreement. Interestingly, we find that the system relaxes towards a mixed phase, depending on the average value of the conserved field, i.e. on the initial condition. Such a phase is characterized by large fluctuations of the phi field.Comment: 13 pages, 8 figures, RevTeX 3.1, submitted to Physical Review

Updated theoretical Period-Age and Period-Age-Color relations for Galactic Classical Cepheids: an application to the Gaia DR2 sample

Updated evolutionary and pulsational model predictions are combined in order to interpret the properties of Galactic Classical Cepheids in the Gaia Data Release 2. In particular, the location of the instability strip boundaries and the analytical relations connecting pulsation periods to the intrinsic stellar parameters are combined with evolutionary tracks to derive reliable and accurate period-age, and the first theoretical period-age-color relations in the Gaia bands for a solar chemical abundance pattern ($Z$=$0.02$, $Y$=$0.28$). The adopted theoretical framework takes into account possible variations in the mass-luminosity relation for the core helium-burning stage as due to changes in the core convective overshooting and/or mass loss efficiency, as well as the impact on the instability strip boundaries due to different assumptions for superadiabatic convection efficiency. The inferred period-age and period-age-color relations are applied to a selected sample of both fundamental and first overtone Gaia Cepheids, and individual ages for the various adopted theoretical scenarios are derived. The retrieved age distributions confirm that a variation in the efficiency of superadiabatic convection in the pulsational model computations has a negligible effect, whereas a brighter Mass-Luminosity relation, as produced by mild overshooting, rotation or mass loss, implies significantly older age predictions. Moreover, older Cepheids are found at larger Galactocentric distances, while first overtone Cepheids are found to be systematically older than the fundamental ones. The comparison with independent age distribution analysis in literature supports the predictive capability of current theoretical framework.Comment: 14 pages, 11 figures, 8 tables, accepted for publication in MNRA

New insights into the use of Ultra Long Period Cepheids as cosmological standard candles

Ultra Long Period Cepheids (ULPs) are pulsating variable stars with a period longer than 80d and have been hypothesized to be the extension of the Classical Cepheids (CCs) at higher masses and luminosities. If confirmed as standard candles, their intrinsic luminosities, 1 to 3 mag brighter than typical CCs, would allow to reach the Hubble flow and, in turn, to determine the Hubble constant, H_0, in one step, avoiding the uncertainties associated with the calibration of primary and secondary indicators. To investigate the accuracy of ULPs as cosmological standard candles, we first collect all the ULPs known in the literature. The resulting sample includes 63 objects with a very large metallicity spread with 12 + log([O/H]) ranging from 7.2 to 9.2 dex. The analysis of their properties in the VI period-Wesenheit plane and in the color-magnitude diagram (CMD) supports the hypothesis that the ULPs are the extension of CCs at longer periods, higher masses and luminosities, even if, additional accurate and homogeneous data and a devoted theoretical scenario are needed to get firm conclusions. Finally, the three M31 ULPs, 8-0326, 8-1498 and H42, are investigated in more detail. For 8-1498 and H42, we cannot confirm their nature as ULPs, due to the inconsistency between their position in the CMD and the measured periods. For 8-0326, the light curve model fitting technique applied to the available time-series data allows us to constrain its intrinsic stellar parameters, distance and reddening.Comment: MNRAS - Accepted 2020 November 19. Received 2020 November 19; in original form 2020 July 15 - 9 pages and 8 figure

Unveiling hidden active nuclei in MaNGA star-forming galaxies with HeIIλ\lambda4686 line emission

Nebular HeII$\lambda$4686\AA~line emission is useful to unveil active galactic nuclei (AGN) residing in actively star-forming (SF) galaxies, typically missed by the standard BPT classification. Here we adopt the HeII diagnostic to identify hidden AGN in the Local Universe using for the first time spatially-resolved data from the Data Release 15 of the Mapping Nearby Galaxies at APO survey (MaNGA DR15). By combining results from HeII and BPT diagnostics, we overall select 459 AGN host candidates ($\sim$10% in MaNGA DR15), out of which 27 are identified as AGN by the HeII diagram only. The HeII-only AGN population is hosted by massive (M$_*\gtrsim10^{10}$ M$_{\odot}$) SF Main Sequence galaxies, and on average less luminous than the BPT-selected AGN. Given the HeII line faintness, we revisit our census accounting for incompleteness effects due to the HeII sensitivity limit of MaNGA. We thus obtain an overall increased fraction (11%) of AGN in MaNGA compared to the BPT-only census (9%), which further increases to 14% for galaxies more massive than $10^{10}$ M$_{\odot}$; interestingly, on the SF Main Sequence the increase is by about a factor of 2. A substantial number of AGN in SF galaxies points to significant, coeval star formation and black hole accretion, consistently with results from hydrodynamical simulations and with important implications on quenching scenarios. In view of exploring unprecedented high redshifts with JWST and new ground-based facilities, revisiting the standard BPT classification through novel emission-line diagnostics is fundamental to discover AGN in highly SF environments.Comment: 13 pages, 12 figures. Accepted for publication in MNRA