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In their early, formative stages star clusters can undergo rapid dynamical evolution leading to strong gravitational interactions and ejection of "runaway" stars at high velocities. While O/B runaway stars have been well studied, lower-mass runaways are so far very poorly characterized, even though they are expected to be much more common. We carried out spectroscopic observations with MAG2-MIKE to follow-up 27 high priority candidate runaways consistent with having been ejected from the Orion Nebula Cluster (ONC) |$\gt 2.5$| Myr ago, based on Gaia astrometry. We derive spectroscopic youth indicators (Li and H |$\alpha$|⁠) and radial velocities, enabling detection of bona fide runaway stars via signatures of youth and 3D traceback. We successfully confirmed 11 of the candidates as low-mass Young Stellar Objects (YSOs) on the basis of our spectroscopic criteria and derived radial velocities (RVs) with which we performed 3D traceback analysis. Three of these confirmed YSOs have kinematic ejection ages |$\gt 4\:$| Myr, with the oldest being 4.7 Myr. Assuming that these stars indeed formed in the ONC and were then ejected, this yields an estimate for the overall formation time of the ONC to be at least |$\sim 5\:$| Myr, i.e. about 10 free-fall times, and with a mean star formation efficiency per free-fall time of |$\bar{\epsilon }_{\rm ff}\lesssim 0.05$|⁠. These results favour a scenario of slow, quasi-equilibrium star cluster formation, regulated by magnetic fields and/or protostellar outflow feedback. [ABSTRACT FROM AUTHOR]

Most stars are born in the crowded environments of gradually forming star clusters. Dynamical interactions between close-passing stars and the evolving ultraviolet radiation fields from proximate massive stars are expected to sculpt the protoplanetary discs (PPDs) in these clusters, potentially contributing to the diversity of planetary systems that we observe. Here, we investigate the impact of cluster environment on disc demographics by implementing simple PPD evolution models within N -body simulations of gradual star cluster formation, containing 50 per cent primordial binaries. We consider a range of star formation efficiency per free-fall time, |$\epsilon _{\rm ff}$|⁠ , and mass surface density of the natal cloud environment, |$\Sigma _{\rm cloud}$|⁠ , both of which affect the overall duration of cluster formation. We track the interaction history of all stars to estimate the dynamical truncation of the discs around stars involved in close encounters. We also track external photoevaporation of the discs due to the ionizing radiation field of the nearby high- and intermediate-mass (⁠|$\gt 5\,{\rm M}_\odot$|⁠) stars. We find that |$\epsilon _{\rm ff}$|⁠ , |$\Sigma _{\rm cloud}$|⁠ , and the presence of primordial binaries have major influences on the masses and radii of the disc population. In particular, external photoevaporation has a greater impact than dynamical interactions in determining the fate of discs in our clusters. [ABSTRACT FROM AUTHOR]

We present an implementation of Pop III.1 seeding of supermassive black holes (SMBHs) in a theoretical model of galaxy formation and evolution to assess the growth of the SMBH population and the properties of the host galaxies. The model of Pop III.1 seeding involves SMBH formation at redshifts |$z\gtrsim 20$| in dark matter minihaloes that are isolated from external radiative feedback, parametrized by isolation distance |$d_{\rm iso}$|⁠. Within a standard |$\Lambda$| CDM cosmology, we generate dark matter haloes using the code pinocchio and seed them according to the Pop III.1 scenario, exploring values of |$d_{\rm iso}$| from 50 to 100 kpc (proper distance). We consider two alternative cases of SMBH seeding: a halo mass threshold model in which all haloes |$\gt 7\times 10^{10}\,\rm M_\odot$| are seeded with |$\sim 10^5\,\rm M_\odot$| black holes; an all light seed model in which all haloes are seeded with low, stellar mass black holes. We follow the redshift evolution of the haloes, populating them with galaxies using the GAlaxy Evolution and Assembly theoretical model of galaxy formation, including accretion on SMBHs and related feedback processes. Here we present predictions for the properties of galaxy populations, focusing on stellar masses, star formation rates, and black hole masses. The local, |$z\sim 0$| metrics of occupation fraction as a function of the galaxy stellar mass, galaxy stellar mass function, and black hole mass function all suggest a constraint of |$d_{\rm iso}\lt 75\:$|  kpc. We discuss the implications of this result for the Pop III.1 seeding mechanism. [ABSTRACT FROM AUTHOR]

Background: Current knowledge of the impact of socioeconomic factors on the risk of admission to the pediatric intensive care unit (PICU) for asthma is limited. Using composite measures of social vulnerability—Social Vulnerability Index (SVI) and Child Opportunity Index (COI) 2.0—we compared patients admitted for status asthmaticus to the PICU and pediatric ward at Children's Hospital Los Angeles (CHLA). We hypothesized patients with a high SVI and low COI are at higher risk for PICU admission. Methods: Patients were identified using ICD‐10 codes for asthma. Primary outcome was admission to PICU versus ward for status asthmaticus. Patient‐registered residential street addresses were geocoded and spatially joined to SVI and COI 2.0 data at the census tract level. Univariate and regression analyses using the patient's SVI, COI 2.0, and admission location were conducted. Results: From January 2017 to March 2022, there were 2458 admissions matched to addresses from 1983 distinct patients. The overall median SVI for all patients was 0.86 (IQR 0.6, 0.9). Overall median COI was 25.0 (IQR 10, 50). There was no difference in SVI or COI for admission to the PICU versus the ward. However, children requiring multiple hospital admissions for asthma were associated with higher SVI and lower COI. Conclusions: Children admitted to CHLA for asthma had an elevated SVI and low COI. There was no difference between admission locations based on SVI or COI scores. This indicates we care for children at increased socioeconomic risk, but this did not increase PICU use for asthma. [ABSTRACT FROM AUTHOR]

Diagnostic imaging, particularly MRI, plays a key role in the evaluation of many spine pathologies. Recent progress in artificial intelligence and its subset, machine learning, has led to many applications within spine MRI, which we sought to examine in this review. A literature search of the major databases (PubMed, MEDLINE, Web of Science, ClinicalTrials.gov) was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The search yielded 1226 results, of which 50 studies were selected for inclusion. Key data from these studies were extracted. Studies were categorized thematically into the following: Image Acquisition and Processing, Segmentation, Diagnosis and Treatment Planning, and Patient Selection and Prognostication. Gaps in the literature and the proposed areas of future research are discussed. Current research demonstrates the ability of artificial intelligence to improve various aspects of this field, from image acquisition to analysis and clinical care. We also acknowledge the limitations of current technology. Future work will require collaborative efforts in order to fully exploit new technologies while addressing the practical challenges of generalizability and implementation. In particular, the use of foundation models and large-language models in spine MRI is a promising area, warranting further research. Studies assessing model performance in real-world clinical settings will also help uncover unintended consequences and maximize the benefits for patient care. [ABSTRACT FROM AUTHOR]

Background: Connexins (Cx) 43 and 40 play a role in leukocytes recruitment in acute inflammation. They are expressed in the endothelial cells. They are also found in the placenta and involved in the placenta development. Acute chorioamnionitis is associated with an increased risk of adverse perinatal outcomes. The aim of this study was to determine the expressions of Cx43 and Cx40 in the placenta of mothers with acute chorioamnionitis, and to correlate their association with the severity of chorioamnionitis and adverse perinatal outcomes. Methods: This study comprised a total of 81 cases, consisting of 39 placenta samples of mothers with acute chorioamnionitis and 42 non-acute chorioamnionitis controls. Cx43 and Cx40 immunohistochemistry were performed on all cases and their expressions were evaluated on cytotrophoblasts, syncytiotrophoblasts, chorionic villi endothelial cells, stem villi endothelial cells, maternal endothelial cells and decidua of the placenta. Results: Primigravida has a significantly higher risk of developing acute chorioamnionitis (p < 0.001). Neonates of mothers with a higher stage of fetal inflammatory response was significantly associated with lung complications (p = 0.041) compared to neonates of mothers with a lower stage. The expression of Cx40 was significantly higher in fetal and maternal vascular endothelial cells in acute chorioamnionitis (p < 0.001 and p = 0.037, respectively) compared to controls. Notably, Cx43 was not expressed in most of the types of cells in the placenta, except for decidua. Both Cx43 and Cx40 expressions did not have correlation with the severity of acute chorioamnionitis and adverse perinatal outcomes. Conclusion: Cx40 was overexpressed in the fetal and maternal vascular endothelial cells in the placenta of mothers with acute chorioamnionitis, and it may have a role in the development of inflammation in placenta. [ABSTRACT FROM AUTHOR]

The presence of carbon-chain molecules in the interstellar medium (ISM) has been known since the early 1970s and > 130 such species have been identified to date, making up ∼ 43 % of the total of detected ISM molecules. They are prevalent not only in star-forming regions in our Galaxy but also in other galaxies. These molecules provide important information on physical conditions, gas dynamics, and evolutionary stages of star-forming regions. Larger species of polycyclic aromatic hydrocarbons (PAHs) and fullerenes (C60 and C70), which may be related to the formation of the carbon-chain molecules, have been detected in circumstellar envelopes around carbon-rich Asymptotic Giant Branch (AGB) stars and planetary nebulae, while PAHs are also known to be a widespread component of the ISM in most galaxies. Recently, two line survey projects toward Taurus Molecular Cloud-1 with large single-dish telescopes have detected many new carbon-chain species, including molecules containing benzene rings. These new findings raise fresh questions about carbon-bearing species in the Universe. This article reviews various aspects of carbon-chain molecules, including observational studies, chemical simulations, quantum calculations, and laboratory experiments, and discusses open questions and how future facilities may answer them. [ABSTRACT FROM AUTHOR]

Introduction: Neonates have a high incidence of respiratory and cardiac perioperative events. Disease severity and indications for surgical intervention often dovetail with an overall complex clinical course and predispose these infants to adverse long‐term neurodevelopmental outcomes and increased length of stay. Our aims were to describe severe and nonsevere early postoperative complications to establish a baseline of care outcomes and to identify subgroups of surgical neonates and procedures for future prospective studies. Methods: Electronic health record data were examined retrospectively for a cohort of patients who had general anesthesia from January 26, 2015 to August 31, 2018. Inclusion criteria were full‐term infants with postmenstrual age less than 44 weeks or premature infants less than 60 weeks postmenstrual age undergoing nonimaging, noncardiac surgery. Severe postoperative complications were defined as mortality, reintubation, positive blood culture, and surgical site infection. Nonsevere early postoperative outcomes were defined as hypoglycemia, hyperglycemia, hypothermia, hyperthermia, and readmission within 30 days. Results: About 2569 procedures were performed in 1842 neonates of which 10.9% were emergency surgeries. There were 120 postoperative severe complications and 965 nonsevere postoperative outcomes. Overall, 30‐day mortality was 1.8% for the first procedure performed, with higher mortality seen on subgroup analysis for patients who underwent exploratory laparotomy (10.3%) and congenital lung lesion resection (4.9%). Postoperative areas for improvement included hyperglycemia (13.9%) and hypothermia (7.9%). Discussion: The mortality rate in our study was comparable to other studies of neonatal surgery despite a high rate of emergency surgery and a high prevalence of prematurity in our cohort. The early outcomes data identified areas for improvement, including prevention of postoperative glucose and temperature derangements. Conclusions: Neonates in this cohort were at risk for severe and nonsevere adverse postoperative outcomes. Future studies are suggested to improve mortality and adverse event rates. [ABSTRACT FROM AUTHOR]