38 research outputs found

    Incidence and Risk Factors for Clinically Confirmed secondary bacterial infections in patients hospitalized for coronavirus disease 2019 (COVID-19)

    Get PDF
    Objective: The true incidence and risk factors for secondary bacterial infections in coronavirus disease 2019 (COVID-19) remains poorly understood. Knowledge of risk factors for secondary infections in hospitalized patients with COVID-19 is necessary to optimally guide selective use of empiric antimicrobial therapy. Design: Single-center retrospective cohort study of symptomatic inpatients admitted for COVID-19 from April 15, 2020, through June 30, 2021. Setting: Academic quaternary-care referral center in Portland, Oregon. Patients: The study included patients who were 18 years or older with a positive severe acute respiratory coronavirus virus 2 (SARS-CoV-2) PCR test up to 10 days prior to admission. Methods: Secondary infections were identified based on clinical, radiographic, and microbiologic data. Logistic regression was used to identify risk factors for secondary infection. We also assessed mortality, length of stay, and empiric antibiotics among those with and without secondary infections. Results: We identified 118 patients for inclusion; 31 (26.3%) had either culture-proven or possible secondary infections among hospitalized patients with COVID-19. Mortality was higher among patients with secondary infections (35.5%) compared to those without secondary infection (4.6%). Empiric antibiotic use on admission was high in both the secondary and no secondary infection groups at 71.0% and 48.3%, respectively. Conclusions: The incidence of secondary bacterial infection was moderate among hospitalized patients with COVID-19. However, a higher proportion of patients received empiric antibiotics regardless of an identifiable secondary infection. Transfer from an outside hospital, baseline immunosuppressant use, and corticosteroid treatment were independent risk factors for secondary infection. Additional studies are needed to validate risk factors and best guide antimicrobial stewardship efforts

    Self-Reported Cognitive Function and Mental Health Diagnoses among Former Professional American-Style Football Players

    Get PDF
    Clinical practice strongly relies on patients' self-report. Former professional American-style football players are hesitant to seek help for mental health problems, but may be more willing to report cognitive symptoms. We sought to assess the association between cognitive symptoms and diagnosed mental health problems and quality of life among a cohort of former professional players. In a cross-sectional design, we assessed self-reported cognitive function using items from the Quality of Life in Neurological Disorders (Neuro-QOL) Item Bank. We then compared mental health diagnoses and quality of life, assessed by items from the Patient-Reported Outcome Measurement Information System (PROMIS ®), between former professional players reporting daily problems in cognitive function and former players not reporting daily cognitive problems. Of the 3758 former professional players included in the analysis, 40.0% reported daily problems due to cognitive dysfunction. Former players who reported daily cognitive problems were more likely to also report depression (18.0% vs. 3.3%, odds ratio [OR] = 6.42, 95% confidence interval [CI] [4.90-8.40]) and anxiety (19.1% vs. 4.3%, OR = 5.29, 95% CI [4.14-6.75]) than those without daily cognitive problems. Further, former players reporting daily cognitive problems were more likely to report memory loss and attention deficit(/hyperactivity) disorder and poorer general mental health, lower quality of life, less satisfaction with social activities and relationships, and more emotional problems. These findings highlight the potential of an assessment of cognitive symptoms for identifying former players with mental health, social, and emotional problems

    An ALMA survey of submillimetre galaxies in the COSMOS field: The extent of the radio-emitting region revealed by 3 GHz imaging with the Very Large Array

    Get PDF
    We determine the radio size distribution of a large sample of 152 SMGs in COSMOS that were detected with ALMA at 1.3 mm. For this purpose, we used the observations taken by the VLA-COSMOS 3 GHz Large Project. One hundred and fifteen of the 152 target SMGs were found to have a 3 GHz counterpart. The median value of the major axis FWHM at 3 GHz is derived to be 4.6±0.44.6\pm0.4 kpc. The radio sizes show no evolutionary trend with redshift, or difference between different galaxy morphologies. We also derived the spectral indices between 1.4 and 3 GHz, and 3 GHz brightness temperatures for the sources, and the median values were found to be α=0.67\alpha=-0.67 and TB=12.6±2T_{\rm B}=12.6\pm2 K. Three of the target SMGs, which are also detected with the VLBA, show clearly higher brightness temperatures than the typical values. Although the observed radio emission appears to be predominantly powered by star formation and supernova activity, our results provide a strong indication of the presence of an AGN in the VLBA and X-ray-detected SMG AzTEC/C61. The median radio-emitting size we have derived is 1.5-3 times larger than the typical FIR dust-emitting sizes of SMGs, but similar to that of the SMGs' molecular gas component traced through mid-JJ line emission of CO. The physical conditions of SMGs probably render the diffusion of cosmic-ray electrons inefficient, and hence an unlikely process to lead to the observed extended radio sizes. Instead, our results point towards a scenario where SMGs are driven by galaxy interactions and mergers. Besides triggering vigorous starbursts, galaxy collisions can also pull out the magnetised fluids from the interacting disks, and give rise to a taffy-like synchrotron-emitting bridge. This provides an explanation for the spatially extended radio emission of SMGs, and can also cause a deviation from the well-known IR-radio correlation.Comment: 32 pages (incl. 5 appendices), 17 figures, 7 tables; accepted for publication in A&A; abstract abridged for arXi

    COSMOS2020: Identification of High-z Protocluster Candidates in COSMOS

    Full text link
    We conduct a systematic search for protocluster candidates at z6z \geq 6 in the COSMOS field using the recently released COSMOS2020 source catalog. We select galaxies using a number of selection criteria to obtain a sample of galaxies that have a high probability of being inside a given redshift bin. We then apply overdensity analysis to the bins using two density estimators, a Weighted Adaptive Kernel Estimator and a Weighted Voronoi Tessellation Estimator. We have found 15 significant (>4σ>4\sigma) candidate galaxy overdensities across the redshift range 6z7.76\le z\le7.7. The majority of the galaxies appear to be on the galaxy main sequence at their respective epochs. We use multiple stellar-mass-to-halo-mass conversion methods to obtain a range of dark matter halo mass estimates for the overdensities in the range of 101113M\sim10^{11-13}\,M_{\rm \odot}, at the respective redshifts of the overdensities. The number and the masses of the halos associated with our protocluster candidates are consistent with what is expected from the area of a COSMOS-like survey in a standard Λ\LambdaCDM cosmology. Through comparison with simulation, we expect that all the overdensities at z6z\simeq6 will evolve into a Virgo-/Coma-like clusters at present (i.e., with masses 10141015M\sim 10^{14}-10^{15}\,M_{\rm \odot}). Compared to other overdensities identified at z6z \geq 6 via narrow-band selection techniques, the overdensities presented appear to have 10×\sim10\times higher stellar masses and star-formation rates. We compare the evolution in the total star-formation rate and stellar mass content of the protocluster candidates across the redshift range 6z7.76\le z\le7.7 and find agreement with the total average star-formation rate from simulations.Comment: 52 pages, 32 figues, 18 tables, main text is 30 pages, appendix is 22 pages, to be published in Ap

    JWST and ALMA discern the assembly of structural and obscured components in a high-redshift starburst galaxy

    Full text link
    We present observations and analysis of the starburst, PACS-819, at z=1.45 (M=1010.7M_*=10^{10.7} M_{ \odot}), using high-resolution (0.10^{\prime \prime}.1; 0.8 kpc) ALMA and multi-wavelength JWST images from the COSMOS-Web program. Dissimilar to HST/ACS images in the rest-frame UV, the redder NIRCam and MIRI images reveal a smooth central mass concentration and spiral-like features, atypical for such an intense starburst. Through dynamical modeling of the CO J=5--4 emission with ALMA, PACS-819 is rotation-dominated thus has a disk-like nature. However, kinematic anomalies in CO and asymmetric features in the bluer JWST bands (e.g., F150W) support a more disturbed nature likely due to interactions. The JWST imaging further enables us to map the distribution of stellar mass and dust attenuation, thus clarifying the relationships between different structural components, not discernable in the previous HST images. The CO J = 5 -- 4 and FIR dust continuum emission are co-spatial with a heavily-obscured starbursting core (<1 kpc) which is partially surrounded by much less obscured star-forming structures including a prominent arc, possibly a tidally-distorted dwarf galaxy, and a clump, either a sign of an ongoing violent disk instability or a recently accreted low-mass satellite. With spatially-resolved maps, we find a high molecular gas fraction in the central area reaching 3\sim3 (MgasM_{\text{gas}}/MM_*) and short depletion times (Mgas/SFRM_{\text{gas}}/SFR\sim 120 Myrs) across the entire system. These observations provide insights into the complex nature of starbursts in the distant universe and underscore the wealth of complementary information from high-resolution observations with both ALMA and JWST.Comment: 18 pages, 12 figures, Submitted to Ap

    COSMOS-Web: Intrinsically Luminous z\gtrsim10 Galaxy Candidates Test Early Stellar Mass Assembly

    Full text link
    We report the discovery of 15 exceptionally luminous 10z1410\lesssim z\lesssim14 candidate galaxies discovered in the first 0.28 deg2^2 of JWST/NIRCam imaging from the COSMOS-Web Survey. These sources span rest-frame UV magnitudes of 20.5>MUV>22-20.5>M_{\rm UV}>-22, and thus constitute the most intrinsically luminous z10z\gtrsim10 candidates identified by JWST to-date. Selected via NIRCam imaging with Hubble ACS/F814W, deep ground-based observations corroborate their detection and help significantly constrain their photometric redshifts. We analyze their spectral energy distributions using multiple open-source codes and evaluate the probability of low-redshift solutions; we conclude that 12/15 (80%) are likely genuine z10z\gtrsim10 sources and 3/15 (20%) likely low-redshift contaminants. Three of our z12z\sim12 candidates push the limits of early stellar mass assembly: they have estimated stellar masses 5×109M\sim5\times10^{9}\,M_\odot, implying an effective stellar baryon fraction of ϵ0.20.5\epsilon_{\star}\sim0.2-0.5, where ϵM/(fbMhalo)\epsilon_{\star}\equiv M_{\star}/(f_{b}M_{halo}). The assembly of such stellar reservoirs is made possible due to rapid, burst-driven star formation on timescales <<100\,Myr where the star-formation rate may far outpace the growth of the underlying dark matter halos. This is supported by the similar volume densities inferred for M1010MM_\star\sim10^{10}\,M_\odot galaxies relative to M109MM_\star\sim10^{9}\,M_\odot -- both about 10610^{-6} Mpc3^{-3} -- implying they live in halos of comparable mass. At such high redshifts, the duty cycle for starbursts would be of order unity, which could cause the observed change in the shape of the UVLF from a double powerlaw to Schechter at z8z\approx8. Spectroscopic redshift confirmation and ensuing constraints of their masses will be critical to understanding how, and if, such early massive galaxies push the limits of galaxy formation in Λ\LambdaCDM.Comment: 30 pages, 9 figures; ApJ submitte

    Uncovering a Massive z~7.65 Galaxy Hosting a Heavily Obscured Radio-Loud QSO Candidate in COSMOS-Web

    Full text link
    In this letter, we report the discovery of the highest redshift, heavily obscured, radio-loud QSO candidate selected using JWST NIRCam/MIRI, mid-IR, sub-mm, and radio imaging in the COSMOS-Web field. Using multi-frequency radio observations and mid-IR photometry, we identify a powerful, radio-loud (RL), growing supermassive black hole (SMBH) with significant spectral steepening of the radio SED (f1.32GHz2f_{1.32 \mathrm{GHz}} \sim 2 mJy, q24μm=1.1q_{24\mu m} = -1.1, α1.323GHz=1.2\alpha_{1.32-3\mathrm{GHz}}=-1.2, Δα=0.4\Delta \alpha = -0.4). In conjunction with ALMA, deep ground-based observations, ancillary space-based data, and the unprecedented resolution and sensitivity of JWST, we find no evidence of QSO contribution to the UV/optical/NIR data and thus infer heavy amounts of obscuration (NH>1023_{\mathrm{H}} > 10^{23} cm2^{-2}). Using the wealth of deep UV to sub-mm photometric data, we report a singular solution photo-z of zphotz_\mathrm{phot} = 7.650.3+0.4^{+0.4}_{-0.3} and estimate an extremely massive host-galaxy (logM=11.92±0.06M\log M_{\star} = 11.92 \pm 0.06\,\mathrm{M}_{\odot}). This source represents the furthest known obscured RL QSO candidate, and its level of obscuration aligns with the most representative but observationally scarce population of QSOs at these epochs.Comment: Submitted to ApJL, Comments welcom

    Unveiling the distant Universe: Characterizing z9z\ge9 Galaxies in the first epoch of COSMOS-Web

    Full text link
    We report the identification of 15 galaxy candidates at z9z\ge9 using the initial COSMOS-Web JWST observations over 77 arcmin2^2 through four NIRCam filters (F115W, F150W, F277W, F444W) with an overlap with MIRI (F770W) of 8.7 arcmin2^2. We fit the sample using several publicly-available SED fitting and photometric redshift codes and determine their redshifts between z=9.3z=9.3 and z=10.9z=10.9 (z=10.0\langle z\rangle=10.0), UV-magnitudes between MUV_{\rm UV} = -21.2 and -19.5 (with \langle MUV=20.2_{\rm UV}\rangle=-20.2) and rest-frame UV slopes (β=2.4\langle \beta\rangle=-2.4). These galaxies are, on average, more luminous than most z9z\ge9 candidates discovered by JWST so far in the literature, while exhibiting similar blue colors in their rest-frame UV. The rest-frame UV slopes derived from SED-fitting are blue (β\beta\sim[-2.0, -2.7]) without reaching extremely blue values as reported in other recent studies at these redshifts. The blue color is consistent with models that suggest the underlying stellar population is not yet fully enriched in metals like similarly luminous galaxies in the lower redshift Universe. The derived stellar masses with log10(\langle \log_{\rm 10} (M/_\star/M)89_\odot)\rangle\approx8-9 are not in tension with the standard Λ\LambdaCDM model and our measurement of the volume density of such UV luminous galaxies aligns well with previously measured values presented in the literature at z910z\sim9-10. Our sample of galaxies, although compact, are significantly resolved.Comment: Submitted to Ap

    Multiorgan MRI findings after hospitalisation with COVID-19 in the UK (C-MORE): a prospective, multicentre, observational cohort study

    Get PDF
    Introduction: The multiorgan impact of moderate to severe coronavirus infections in the post-acute phase is still poorly understood. We aimed to evaluate the excess burden of multiorgan abnormalities after hospitalisation with COVID-19, evaluate their determinants, and explore associations with patient-related outcome measures. Methods: In a prospective, UK-wide, multicentre MRI follow-up study (C-MORE), adults (aged ≥18 years) discharged from hospital following COVID-19 who were included in Tier 2 of the Post-hospitalisation COVID-19 study (PHOSP-COVID) and contemporary controls with no evidence of previous COVID-19 (SARS-CoV-2 nucleocapsid antibody negative) underwent multiorgan MRI (lungs, heart, brain, liver, and kidneys) with quantitative and qualitative assessment of images and clinical adjudication when relevant. Individuals with end-stage renal failure or contraindications to MRI were excluded. Participants also underwent detailed recording of symptoms, and physiological and biochemical tests. The primary outcome was the excess burden of multiorgan abnormalities (two or more organs) relative to controls, with further adjustments for potential confounders. The C-MORE study is ongoing and is registered with ClinicalTrials.gov, NCT04510025. Findings: Of 2710 participants in Tier 2 of PHOSP-COVID, 531 were recruited across 13 UK-wide C-MORE sites. After exclusions, 259 C-MORE patients (mean age 57 years [SD 12]; 158 [61%] male and 101 [39%] female) who were discharged from hospital with PCR-confirmed or clinically diagnosed COVID-19 between March 1, 2020, and Nov 1, 2021, and 52 non-COVID-19 controls from the community (mean age 49 years [SD 14]; 30 [58%] male and 22 [42%] female) were included in the analysis. Patients were assessed at a median of 5·0 months (IQR 4·2–6·3) after hospital discharge. Compared with non-COVID-19 controls, patients were older, living with more obesity, and had more comorbidities. Multiorgan abnormalities on MRI were more frequent in patients than in controls (157 [61%] of 259 vs 14 [27%] of 52; p&lt;0·0001) and independently associated with COVID-19 status (odds ratio [OR] 2·9 [95% CI 1·5–5·8]; padjusted=0·0023) after adjusting for relevant confounders. Compared with controls, patients were more likely to have MRI evidence of lung abnormalities (p=0·0001; parenchymal abnormalities), brain abnormalities (p&lt;0·0001; more white matter hyperintensities and regional brain volume reduction), and kidney abnormalities (p=0·014; lower medullary T1 and loss of corticomedullary differentiation), whereas cardiac and liver MRI abnormalities were similar between patients and controls. Patients with multiorgan abnormalities were older (difference in mean age 7 years [95% CI 4–10]; mean age of 59·8 years [SD 11·7] with multiorgan abnormalities vs mean age of 52·8 years [11·9] without multiorgan abnormalities; p&lt;0·0001), more likely to have three or more comorbidities (OR 2·47 [1·32–4·82]; padjusted=0·0059), and more likely to have a more severe acute infection (acute CRP &gt;5mg/L, OR 3·55 [1·23–11·88]; padjusted=0·025) than those without multiorgan abnormalities. Presence of lung MRI abnormalities was associated with a two-fold higher risk of chest tightness, and multiorgan MRI abnormalities were associated with severe and very severe persistent physical and mental health impairment (PHOSP-COVID symptom clusters) after hospitalisation. Interpretation: After hospitalisation for COVID-19, people are at risk of multiorgan abnormalities in the medium term. Our findings emphasise the need for proactive multidisciplinary care pathways, with the potential for imaging to guide surveillance frequency and therapeutic stratification

    Fatal and Nonfatal Opioid Overdose Risk Following Release from Prison: A Retrospective Cohort Study Using Linked Administrative Data.

    No full text
    Among individuals who are released from prison, opioid overdose is a leading cause of death with a risk more than ten-fold the general population. Although the epidemiology of opioid-related fatalities has been described, few studies have characterized both fatal and nonfatal opioid-related poisonings. The objective of this study was to estimate risk of fatal and nonfatal opioid overdose among adults released from prison
    corecore