857 research outputs found
Detection of Intracluster Globular Clusters in the First JWST Images of the Gravitational Lens Cluster SMACS J0723.3-7327 at z = 0.39
We present a survey of globular clusters (GCs) in the massive gravitational
lens cluster SMACS J0723.3-7327 at based on the early released
JWST/NIRCam images. In the color-magnitude diagrams of the point sources we
find clearly a rich population of intracluster GCs that spread in a wide area
of the cluster. Their ages, considering the cluster redshift, are younger than
9.5 Gyr. The F200W (AB) magnitudes of these GCs, mag,
correspond to mag, showing that they belong to the
brightest GCs (including ultracompact dwarfs). The spatial distributions of
these GCs show a megaparsec-scale structure elongated along the major axis of
the brightest cluster galaxy. In addition, they show a large number of
substructures, some of which are consistent with the substructures seen in the
map of diffuse intracluster light. The GC number density map is, in general,
consistent with the dark matter mass density map based on the strong lensing
analysis in the literature. The radial number density profile of the GCs in the
outer region is steeper than the dark matter mass profile obtained from lensing
models. These results are consistent with those for the GCs found in the deep
HST images of Abell 2744, another massive cluster at , and in
simulated galaxy clusters. This shows that the intracluster GCs are an
excellent independent tool to probe the dark matter distribution in galaxy
clusters as well as to reveal the cluster assembly history in the JWST era.Comment: 25 pages, 12 figures, Accepted for publication in ApJ
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Comparison of the Plasma Metabolome Profiles Between the Internal Thoracic Artery and Ascending Aorta in Patients Undergoing Coronary Artery Bypass Graft Surgery Using Gas Chromatography Time-of-Flight Mass Spectrometry.
BackgroundThe left internal thoracic artery (LITA) has been used as the first conduit of choice in coronary artery bypass grafting (CABG) because of excellent long-term patency and outcomes. However, no studies have examined substances other than nitric oxide that could be beneficial for the bypass conduit, native coronary artery or ischemic myocardium. This study was conducted to evaluate differences in metabolic profiles between the LITA and ascending aorta using gas chromatography-time of flight-mass spectrometry (GC-TOF-MS).MethodsTwenty patients who underwent CABG using the LITA were prospectively enrolled. Plasma samples were collected simultaneously from the LITA and ascending aorta. GC-TOF-MS based untargeted metabolomic analyses were performed and a 2-step volcano plot analysis was used to identify distinguishable markers from two plasma metabolome profiles. Semi-quantitative and quantitative analyses were performed using GC-TOF-MS and enzyme-linked immunosorbent assay, respectively, after selecting target metabolites based on the metabolite set enrichment analysis.ResultsInitial volcano plot analysis demonstrated 5 possible markers among 851 peaks detected. The final analysis demonstrated that the L-cysteine peak was significantly higher in the LITA than in the ascending aorta (fold change = 1.86). The concentrations of intermediate metabolites such as L-cysteine, L-methionine and L-cystine in the 'cysteine and methionine metabolism pathway' were significantly higher in the LITA than in the ascending aorta (2.0-, 1.4- and 1.2-fold, respectively). Quantitative analysis showed that the concentration of hydrogen sulfide (HโS) was significantly higher in the LITA.ConclusionThe plasma metabolome profiles of the LITA and ascending aorta were different, particularly higher plasma concentrations of L-cysteine and HโS in the LITA
To the Edge of M87 and Beyond: Spectroscopy of Intracluster Globular Clusters and Ultra Compact Dwarfs in the Virgo Cluster
We present the results from a wide-field spectroscopic survey of globular
clusters (GCs) in the Virgo Cluster. We obtain spectra for 201 GCs and 55
ultracompact dwarfs (UCDs) using the Hectospec on the Multiple Mirror
Telescope, and derive their radial velocities. We identify 46 genuine
intracluster GCs (IGCs), not associated with any Virgo galaxies, using the 3D
GMM test on the spatial and radial velocity distribution.They are located at
the projected distance 200 kpc R 500 kpc from the center
of M87. The radial velocity distribution of these IGCs shows two peaks, one at
= 1023 km s associated with the Virgo main body, and another
at = 36 km s associated with the infalling structure. The
velocity dispersion of the IGCs in the Virgo main body is 314 km s, which is smoothly connected to the velocity dispersion
profile of M87 GCs, but much lower than that of dwarf galaxies in the same
survey field, 608 km s. The UCDs are more
centrally concentrated on massive galaxies, M87, M86, and M84. The radial
velocity dispersion of the UCD system is much smaller than that of dwarf
galaxies. Our results confirm the large-scale distribution of Virgo IGCs
indicated by previous photometric surveys. The color distribution of the
confirmed IGCs shows a bimodality similar to that of M87 GCs. This indicates
that most IGCs are stripped off from dwarf galaxies and some from massive
galaxies in the Virgo.Comment: 19 pages, 20 figures, 8 tables, accepted for publication in Ap
Primary Pulmonary Plasmacytoma Presenting as Multiple Lung Nodules
Extramedullary plasmacytoma is a plasma cell tumor arising outside the bone marrow and usually occurs as a solitary tumor in the upper respiratory tract, such as the pharynx, paranasal sinuses, nasal cavity, or oral cavity [1]. Other cases develop in the lymph nodes, skin, gastrointestinal tract, genitourinary tract, and other regions. Primary pulmonary plasmacytomas are very rare and usually present as solitary lung nodules or masses [2]. Unusual cases manifest as diffuse pulmonary infiltration [3,4]. We describe here a unique case of primary pulmonary plasmacytoma, which presented as multiple lung nodules during regular screening in a patient with systemic lupus erythematosus
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