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Coronary atherosclerosis scoring with semiquantitative CCTA risk scores for prediction of major adverse cardiac events: Propensity score-based analysis of diabetic and non-diabetic patients.
AIMS:We aimed to compare semiquantitative coronary computed tomography angiography (CCTA) risk scores - which score presence, extent, composition, stenosis and/or location of coronary artery disease (CAD) - and their prognostic value between patients with and without diabetes mellitus (DM). Risk scores derived from general chest-pain populations are often challenging to apply in DM patients, because of numerous confounders. METHODS:Out of a combined cohort from the Leiden University Medical Center and the CONFIRM registry with 5-year follow-up data, we performed a secondary analysis in diabetic patients with suspected CAD who were clinically referred for CCTA. A total of 732 DM patients was 1:1 propensity-matched with 732 non-DM patients by age, sex and cardiovascular risk factors. A subset of 7 semiquantitative CCTA risk scores was compared between groups: 1) any stenosis ≥50%, 2) any stenosis ≥70%, 3) stenosis-severity component of the coronary artery disease-reporting and data system (CAD-RADS), 4) segment involvement score (SIS), 5) segment stenosis score (SSS), 6) CT-adapted Leaman score (CT-LeSc), and 7) Leiden CCTA risk score. Cox-regression analysis was performed to assess the association between the scores and the primary endpoint of all-cause death and non-fatal myocardial infarction. Also, area under the receiver-operating characteristics curves were compared to evaluate discriminatory ability. RESULTS:A total of 1,464 DM and non-DM patients (mean age 58 ± 12 years, 40% women) underwent CCTA and 155 (11%) events were documented after median follow-up of 5.1 years. In DM patients, the 7 semiquantitative CCTA risk scores were significantly more prevalent or higher as compared to non-DM patients (p ≤ 0.022). All scores were independently associated with the primary endpoint in both patients with and without DM (p ≤ 0.020), with non-significant interaction between the scores and diabetes (interaction p ≥ 0.109). Discriminatory ability of the Leiden CCTA risk score in DM patients was significantly better than any stenosis ≥50% and ≥70% (p = 0.003 and p = 0.007, respectively), but comparable to the CAD-RADS, SIS, SSS and CT-LeSc that also focus on the extent of CAD (p ≥ 0.265). CONCLUSION:Coronary atherosclerosis scoring with semiquantitative CCTA risk scores incorporating the total extent of CAD discriminate major adverse cardiac events well, and might be useful for risk stratification of patients with DM beyond the binary evaluation of obstructive stenosis alone
Clinical risk factors and atherosclerotic plaque extent to define risk for major events in patients without obstructive coronary artery disease: the long-term coronary computed tomography angiography CONFIRM registry.
AimsIn patients without obstructive coronary artery disease (CAD), we examined the prognostic value of risk factors and atherosclerotic extent.Methods and resultsPatients from the long-term CONFIRM registry without prior CAD and without obstructive (≥50%) stenosis were included. Within the groups of normal coronary computed tomography angiography (CCTA) (N = 1849) and non-obstructive CAD (N = 1698), the prognostic value of traditional clinical risk factors and atherosclerotic extent (segment involvement score, SIS) was assessed with Cox models. Major adverse cardiac events (MACE) were defined as all-cause mortality, non-fatal myocardial infarction, or late revascularization. In total, 3547 patients were included (age 57.9 ± 12.1 years, 57.8% male), experiencing 460 MACE during 5.4 years of follow-up. Age, body mass index, hypertension, and diabetes were the clinical variables associated with increased MACE risk, but the magnitude of risk was higher for CCTA defined atherosclerotic extent; adjusted hazard ratio (HR) for SIS >5 was 3.4 (95% confidence interval [CI] 2.3-4.9) while HR for diabetes and hypertension were 1.7 (95% CI 1.3-2.2) and 1.4 (95% CI 1.1-1.7), respectively. Exclusion of revascularization as endpoint did not modify the results. In normal CCTA, presence of ≥1 traditional risk factors did not worsen prognosis (log-rank P = 0.248), while it did in non-obstructive CAD (log-rank P = 0.025). Adjusted for SIS, hypertension and diabetes predicted MACE risk in non-obstructive CAD, while diabetes did not increase risk in absence of CAD (P-interaction = 0.004).ConclusionAmong patients without obstructive CAD, the extent of CAD provides more prognostic information for MACE than traditional cardiovascular risk factors. An interaction was observed between risk factors and CAD burden, suggesting synergistic effects of both
UNCOVER:A NIRSpec Identification of a Broad-line AGN at z = 8.50
Deep observations with the James Webb Space Telescope (JWST) have revealed an emerging population of red pointlike sources that could provide a link between the postulated supermassive black hole seeds and observed quasars. In this work, we present a JWST/NIRSpec spectrum from the JWST Cycle 1 UNCOVER Treasury survey of a massive accreting black hole at z = 8.50 displaying a clear broad-line component as inferred from the Hβ line with FWHM = 3439 ± 413 km s−1, typical of the broad-line region of an active galactic nucleus (AGN). The AGN nature of this object is further supported by high ionization, as inferred from emission lines, and a point-source morphology. We compute a black hole mass of log 10 ( M BH / M ⊙ ) = 8.17 ± 0.42 and a bolometric luminosity of L bol ∼ 6.6 × 1045 erg s−1. These values imply that our object is accreting at ∼40% of the Eddington limit. Detailed modeling of the spectral energy distribution in the optical and near-infrared, together with constraints from ALMA, indicate an upper limit on the stellar mass of log 10 ( M * / M ⊙ ) < 8.7 , which would lead to an unprecedented ratio of black hole to host mass of at least ∼30%. This is orders of magnitude higher compared to the local QSOs but consistent with recent AGN studies at high redshift with JWST. This finding suggests that a nonnegligible fraction of supermassive black holes either started out from massive seeds and/or grew at a super-Eddington rate at high redshift. Given the predicted number densities of high-z faint AGN, future NIRSpec observations of larger samples will allow us to further investigate galaxy-black hole coevolution in the early Universe.</p
Inside the bubble: exploring the environments of reionisation-era Lyman-α emitting galaxies with JADES and FRESCO⋆
© 2024 The Author(s). Published by EDP Sciences. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY), https://creativecommons.org/licenses/by/4.0/We present a study of the environments of 17 Lyman-α emitting galaxies (LAEs) in the reionisation-era (5.8 5%) observed in our sample of LAEs, suggesting the presence of ionised hydrogen along the line of sight towards at least eight out of 17 LAEs. We find minimum physical 'bubble'sizes of the order of R ion ∼ 0.1- 1pMpc are required in a patchy reionisation scenario where ionised bubbles containing the LAEs are embedded in a fully neutral IGM. Around half of the LAEs in our sample are found to coincide with large-scale galaxy overdensities seen in FRESCO at z ∼ 5.8- 5.9 and z ∼ 7.3, suggesting Lyman-α transmission is strongly enhanced in such overdense regions, and underlining the importance of LAEs as tracers of the first large-scale ionised bubbles. Considering only spectroscopically confirmed galaxies, we find our sample of UV-faint LAEs (M UV ≳ -20mag) and their direct neighbours are generally not able to produce the required ionised regions based on the Lyman-α transmission properties, suggesting lower-luminosity sources likely play an important role in carving out these bubbles. These observations demonstrate the combined power of JWST multi-object and slitless spectroscopy in acquiring a unique view of the early Universe during cosmic reionisation via the most distant LAEs.Peer reviewe
DUALZ: Deep UNCOVER-ALMA Legacy High-Z Survey
We present the survey design and initial results of the ALMA Cycle 9 program
of DUALZ, which aims to establish a joint ALMA and JWST public legacy field
targeting the massive galaxy cluster Abell 2744. DUALZ features a contiguous
ALMA 30-GHz-wide mosaic in Band 6, covering areas of down
to a sensitivity of Jy. Through a blind search, we identified
69 dust continuum sources at S/N with median redshift and
intrinsic 1.2-mm flux of and ~mJy. Of
these, 27 have been spectroscopically confirmed, leveraged by the latest
NIRSpec observations, while photometric redshift estimates are constrained by
the comprehensive HST, NIRCam, and ALMA data for the remaining sources. With
priors, we further identify a [CII]158 m line emitter at
, confirmed by the latest NIRSpec spectroscopy. The NIRCam
counterparts of the 1.2-mm continuum exhibit undisturbed morphologies, denoted
either by disk or spheroid, implying the triggers for the faint mm emission are
less catastrophic than mergers. We have identified 8 HST-dark galaxies
(F150W27mag, F150WF444W2.3) and 2 JWST-dark (F444W30mag) galaxy
candidates among the ALMA continuum sources. The former includes face-on disk
galaxies, hinting that substantial dust obscuration does not always result from
inclination. We also detect a marginal dust emission from an X-ray-detected
galaxy at , suggesting an active co-evolution of the
central black hole and its host. We assess the infrared luminosity function up
to and find it consistent with predictions from galaxy formation
models. To foster diverse scientific outcomes from the community, we publicly
release reduced ALMA mosaic maps, cubes, and the source catalog.Comment: 33 pages, 16 figures, and 5 tables. Submitted to ApJS. The ALMA
products are fully available from here:
https://jwst-uncover.github.io/DR2.html#DUAL
UNCOVER: A NIRSpec Identification of a Broad Line AGN at z = 8.50
Deep observations with JWST have revealed an emerging population of red
point-like sources that could provide a link between the postulated
supermassive black hole seeds and observed quasars. In this work we present a
JWST/NIRSpec spectrum from the JWST Cycle 1 UNCOVER Treasury survey, of a
massive accreting black hole at , displaying a clear broad-line
component as inferred from the H line with FWHM = km
s, typical of the broad line region of an active galactic nucleus (AGN).
The AGN nature of this object is further supported by high ionization, as
inferred from emission lines, and a point-source morphology. We compute the
black hole mass of log, and a bolometric
luminosity of erg s. These values
imply that our object is accreting at of the Eddington limit.
Detailed modeling of the spectral energy distribution in the optical and
near-infrared, together with constraints from ALMA, indicate an upper limit on
the stellar mass of log, which would lead to an
unprecedented ratio of black hole to host mass of at least . This
is orders of magnitude higher compared to the local QSOs, but is consistent
with recent AGN studies at high redshift with JWST. This finding suggests that
a non-negligible fraction of supermassive black holes either started out from
massive seeds and/or grew at a super-Eddington rate at high redshift. Given the
predicted number densities of high- faint AGN, future NIRSpec observations
of larger samples will allow us to further investigate the galaxy-black hole
co-evolution in the early Universe.Comment: 14 pages, 6 figures, 2 tables. Submitted to ApJ
A telephone survey of parental attitudes and behaviours regarding teenage drinking
<p>Abstract</p> <p>Background</p> <p>Irish teenagers demonstrate high rates of drunkenness and there has been a progressive fall in age of first drinking in recent decades. International research indicates that parents exert substantial influence over their teenager's drinking. We sought to determine the attitudes and behaviours of Irish parents towards drinking by their adolescent children.</p> <p>Methods</p> <p>We conducted a telephone survey of a representative sample of of 234 parents who had a teenager aged between 13 and 17 years.</p> <p>Results</p> <p>Six per cent reported that they would be unconcerned if their son or daughter was to binge drink once per month. On the issue of introducing children to alcohol in the home, 27% viewed this as a good idea while 63% disagreed with this practice. Eleven per cent of parents reported that they had given a drink to their teenager at home. Parents who drank regularly themselves, who were from higher socio-demographic groups and who lived in the east of Ireland demonstrated more permissive attitudes to teenage drinking.</p> <p>Conclusions</p> <p>We found no evidence of widespread permissive attitudes and behaviours among Irish parents. Given that parental influences have been demonstrated to exert substantial impact on teenage drinking, it may be possible to harness the concerns of Irish parents more effectively to reverse the trends of escalating alcohol related harm in Ireland.</p
UNCOVER: A NIRSpec Census of Lensed Galaxies at z=8.50-13.08 Probing a High AGN Fraction and Ionized Bubbles in the Shadow
We present JWST NIRSpec prism spectroscopy of gravitationally lensed galaxies
at found behind the massive galaxy cluster Abell 2744 in the
UNCOVER Cycle 1 Treasury Program. We confirm the source redshift via emission
lines and/or the Ly break feature for ten galaxies at z=8.50-13.08 down
to . We achieve a high confirmation rate of 100\% for
candidates reported in Atek et al. (2023). Using six sources with multiple
emission line detections, we find that the offset of the redshift estimates
between the lines and the Ly break alone with prism can be as large as
, raising caution in designing future follow-up spectroscopy for the
break-only sources. With spec- confirmed sources in UNCOVER and the
literature, we derive lower limits on the rest-frame ultraviolet (UV)
luminosity function (LF) at -12 and find these lower limits to be
consistent with recent photometric measurements. We identify at least two
unambiguous and several possible active galactic nucleus (AGN) systems based on
X-ray emission, broad line (BL) H, high ionization line (e.g., NIV]1487,
CIV1549) detections, and excess in UVLF. This requires the AGN LFs at
9-10 to be comparable or even higher than the X-ray AGN LF estimated at
and indicates a plausible cause of the high abundance of
galaxies claimed in recent photometric studies may be AGNs. One UV-luminous
source is confirmed at the same redshift as a dusty BL AGN at with a
physical separation of 380 kpc in the source plane. These two sources show
blueward Ly line or continuum emission, suggesting that they reside in
the same ionized bubble with a radius of pMpc. Our results imply
that AGNs have a non-negligible contribution to cosmic reionization.Comment: 27 pages, 11 figures, 4 tables, submitted to ApJ (See also
arXiv:2308.11610
The Star-forming and Ionizing Properties of Dwarf z~6-9 Galaxies in JADES: Insights on Bursty Star Formation and Ionized Bubble Growth
Reionization is thought to be driven by faint star-forming galaxies, but
characterizing this population in detail has long remained very challenging.
Here we utilize deep nine-band NIRCam imaging from JADES to study the
star-forming and ionizing properties of 756 galaxies, including
hundreds of very UV-faint objects (). The faintest
() galaxies in our sample typically have stellar masses of
and young light-weighted ages (50
Myr), though some show strong Balmer breaks implying much older ages (500
Myr). We find no evidence for extremely massive galaxies (
) in our sample. We infer a strong (factor 2) decline in the
typical [OIII]H EWs towards very faint galaxies, yet a
weak UV luminosity dependence on the H EWs at . We demonstrate
that these EW trends can be explained if fainter galaxies have systematically
lower metallicities as well as more recently-declining star formation histories
relative to the most UV-luminous galaxies in our sample. Our data provide
evidence that the brightest galaxies are frequently experiencing a recent
strong upturn in SFR. We also discuss how the EW trends may be influenced by a
strong correlation between and Lyman continuum escape fraction.
This alternative explanation has dramatically different implications for the
contribution of galaxies along the luminosity function to cosmic reionization,
highlighting the need for deep spectroscopic follow-up. Finally, we quantify
the photometric overdensities around two strong Ly emitters in
the JADES footprint. One Ly emitter lies close to a strong photometric
overdensity while the other shows no significant nearby overdensity, perhaps
implying that not all strong Ly emitters reside in large ionized
bubbles.Comment: 29 pages, 16 figures. Submitted to MNRAS. Comments welcom
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