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The relation between nuclear star clusters (NSCs) and the growth of the central supermassive black holes (SMBHs), as well as their connection to the properties of the host galaxies, is crucial for understanding the evolution of galaxies. Recent observations have revealed that about 10 per cent of nucleated galaxies host hybrid nuclei, consisting of both NSCs and accreting SMBHs that power active galactic nuclei (AGNs). Motivated by the potential of the recently published multiwavelength data sets from LeMMINGs survey, here we present the most thorough investigation to date of the incidence of hybrid nuclei in a large sample of 100 nearby nucleated galaxies (10 E, 25 S0, 63 S, and 2 Irr), covering a wide range in stellar mass (⁠|$M_{*,\rm gal} \sim 10^{8.7}-10^{12}~\rm M_{\odot }$|⁠). We identify the nuclei and derive their properties by performing detailed 1D and 2D multicomponent decompositions of the optical and near-infrared HST stellar light distributions of the galaxies using Sérsic and core-Sérsic models. Our AGN diagnostics are based on homogeneously derived nuclear 1.5 GHz e -MERLIN radio, Chandra X-ray (0.3–10 keV), and optical emission-line data. We determine the nucleation fraction (⁠|$f_{\rm nuc}$|⁠) as the relative incidence of nuclei across the LeMMINGs HST sample and find |$f_{\rm nuc} =~$| 100/149 (= 67 |$\pm$| 7 per cent), confirming previous work, with a peak value of |$49/56~(= 88 \pm 13$|  per cent) at bulge masses |$M_{*,\rm bulge}\sim 10^{9.4}- 10^{10.8}~ \rm M_{\odot }$|⁠. We identify 30 nucleated LeMMINGs galaxies that are optically active, radio-detected, and X-ray luminous (⁠|$L_\textnormal {X} \gt 10^{39}$| erg s |$^{-1}$|⁠). This indicates that our nucleated sample has a lower limit |$\sim$| 30 per cent occupancy of hybrid nuclei, which is a function of |$M_{*,\rm bulge}$| and |$M_{*,\rm gal}$|⁠. We find that hybrid nuclei have a number density of |$(1.5 \pm 0.4)\times 10^{-5}$|  Mpc |$^{-3}$|⁠ , are more common at |$M_{*,\rm gal}\sim 10^{10.6}- 10^{11.8}~\rm M_{\odot }$| and occur, at least, three times more frequently than previously reported. [ABSTRACT FROM AUTHOR]

All 280 of the statistically complete Palomar sample of nearby (<120 Mpc) galaxies δ > 20° have been observed at 1.5 GHz as part of the LeMMINGs e -MERLIN legacy survey. Here, we present Chandra X-ray observations of the nuclei of 213 of these galaxies, including a statistically complete sub-set of 113 galaxies in the declination range 40° <δ < 65°. We observed galaxies of all optical spectral types, including 'active' galaxies [e.g. low-ionization nuclear emission line regions (LINERs) and Seyferts] and 'inactive' galaxies like |${\rm H\, \small {II}}$| galaxies and absorption line galaxies (ALG). The X-ray flux limit of our survey is 1.65 × 10−14 erg s−1 cm−2 (0.3−10 keV). We detect X-ray emission coincident within 2 arcsec of the nucleus in 150/213 galaxies, including 13/14 Seyferts, 68/77 LINERs, 13/22 ALGs and 56/100 |${\rm H\, \small {II}}$| galaxies, but cannot completely rule out contamination from non-AGN processes in sources with nuclear luminosities |$\lesssim 10^{39}$|  erg s−1. We construct an X-ray Luminosity function (XLF) and find that the local galaxy XLF, when including all active galactic nucleus (AGN) types, can be represented as a single power law of slope −0.54 ± 0.06. The Eddington ratio of the Seyferts is usually 2−4 decades higher than that of the LINERs, ALGs, and |${\rm H\, \small {II}}$| galaxies, which are mostly detected with Eddington ratios |$\lesssim 10^{-3}$|⁠. Using [ |${\rm O\, \small {III}}$| ] line measurements and black hole masses from the literature, we show that LINERs, |${\rm H\, \small {II}}$| galaxies and ALGs follow similar correlations to low luminosities, suggesting that some 'inactive' galaxies may harbour AGN. [ABSTRACT FROM AUTHOR]

What determines the nuclear radio emission in local galaxies? To address this question, we combine optical [O  iii ] line emission, robust black hole (BH) mass estimates, and high-resolution e- MERLIN 1.5-GHz data, from the LeMMINGs survey, of a statistically complete sample of 280 nearby optically active (LINER and Seyfert) and inactive [H  ii and absorption line galaxies (ALGs)] galaxies. Using [O  iii ] luminosity (⁠|$L_{\rm [O\, \small {III}]}$|⁠) as a proxy for the accretion power, local galaxies follow distinct sequences in the optical–radio planes of BH activity, which suggest different origins of the nuclear radio emission for the optical classes. The 1.5-GHz radio luminosity of their parsec-scale cores (L core) is found to scale with BH mass (M BH) and [O  iii ] luminosity. Below M BH ∼ 106.5 M⊙, stellar processes from non-jetted H  ii galaxies dominate with |$L_{\rm core} \propto M_{\rm BH}^{0.61\pm 0.33}$| and |$L_{\rm core} \propto L_{\rm [O\, \small {III}]}^{0.79\pm 0.30}$|⁠. Above M BH ∼ 106.5 M⊙, accretion-driven processes dominate with |$L_{\rm core} \propto M_{\rm BH}^{1.5-1.65}$| and |$L_{\rm core} \propto L_{\rm [O\, \small {III}]}^{0.99-1.31}$| for active galaxies: radio-quiet/loud LINERs, Seyferts, and jetted H  ii galaxies always display (although low) signatures of radio-emitting BH activity, with |$L_{\rm 1.5\, GHz}\gtrsim 10^{19.8}$| W Hz−1 and M BH ≳ 107 M⊙, on a broad range of Eddington-scaled accretion rates (⁠|$\dot{m}$|⁠). Radio-quiet and radio-loud LINERs are powered by low- |$\dot{m}$| discs launching sub-relativistic and relativistic jets, respectively. Low-power slow jets and disc/corona winds from moderately high to high- |$\dot{m}$| discs account for the compact and edge-brightened jets of Seyferts, respectively. Jetted H  ii galaxies may host weakly active BHs. Fuel-starved BHs and recurrent activity account for ALG properties. In conclusion, specific accretion–ejection states of active BHs determine the radio production and the optical classification of local active galaxies. [ABSTRACT FROM AUTHOR]

Objectives: For neonates and infants with aortic valve pathology, the Ross procedure historically has been associated with high rates of morbidity and mortality. Data regarding long-term durability are lacking., Methods: The international, multi-institutional Ross Collaborative included 6 tertiary care centers. Infants who underwent a Ross operation between 1996 and 2016 (allowing a minimum 5 years of follow-up) were retrospectively identified. Serial echocardiograms were examined to study evolution in neoaortic size and function., Results: Primary diagnoses for the 133 patients (n = 30 neonates) included isolated aortic stenosis (14%, n = 19), Shone complex (14%, n = 19), and aortic stenosis plus other (excluding Shone complex; n = 95, 71%), including arch obstruction (n = 55), left ventricular hypoplasia (n = 9), and mitral disease (moderate or greater stenosis or regurgitation, n = 31). At the time of the Ross procedure, median age was 96 days (interquartile range, 36-186), and median weight was 4.4 kg (3.6-6.5). In-hospital mortality occurred in 13 of 133 patients (10%) (4/30 [13%] neonates). Postdischarge mortality occurred in 10 of 120 patients (8%) at a median of 298 days post-Ross. Post-Ross neoaortic dilatation occurred, peaking at 4 to 5 SDs above normal at 2 to 3 years before returning to near-baseline z-score at a median follow-up of 11.5 [6.4-17.4] years. Autograft/left ventricular outflow tract reintervention was required in 5 of 120 patients (4%) at a median of 10.3 [4.1-12.8] years. Freedom from moderate or greater neoaortic regurgitation was 86% at 15 years., Conclusions: Neonates and infants experience excellent postdischarge survival and long-term freedom from autograft reintervention and aortic regurgitation after the Ross. Neoaortic dilatation normalizes in this population in the long-term. Increased consideration should be given to Ross in neonates and infants with aortic valve disease., Competing Interests: Conflict of Interest Statement The authors reported no conflicts of interest. The Journal policy requires editors and reviewers to disclose conflicts of interest and to decline handling or reviewing manuscripts for which they may have a conflict of interest. The editors and reviewers of this article have no conflicts of interest., (Copyright © 2024 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.)

Background: Pulmonary artery banding (PAB) in isolation or combined with a congenital cardiac surgical procedure is common and has important mortality. We aimed to determine patient characteristics, clinical outcomes, variation in clinical outcomes by diagnoses, and center variation in PAB use., Methods: Using The Society of Thoracic Surgeons Congenital Heart Surgery Database (STS CHSD), this study evaluated outcomes of patients undergoing PAB across diagnoses, participating centers, and additional procedures. Patients were identified by procedure and diagnosis codes from 2016 to 2019. We separated patients into groups of main and bilateral PAB and described their outcomes, focusing on patients with main PAB., Results: This study identified 3367 PAB procedures from 2016 to 2019 (3% of all STS CHSD cardiovascular cases during this period): 2677 main PAB, 690 bilateral PAB. Operative mortality was 8% after main PAB and 26% after bilateral PAB. There was significant variation in use of main PAB by center, with 115 centers performing at least 1 main PAB procedure (range, 1-134; Q1-Q3, 8-33). For patients with main PAB, there were substantial differences in mortality, depending on timing of main PAB relative to other procedures. The highest operative mortality (25%; P < .0001) was in patients who underwent main PAB after another separate procedure during their admission, with extracorporeal membrane oxygenation being the most frequent preceding procedure., Conclusions: PAB is a frequently used congenital cardiac procedure with high mortality and variation in use across centers. Outcomes vary widely by banding type and patient diagnosis. Main PAB after cardiac surgical procedures, especially extracorporeal membrane oxygenation, is associated with very high operative mortality., (Copyright © 2024 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)