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The astrophysical journal 930(1), 52 (2022). doi:10.3847/1538-4357/ac6171, We have modeled the velocity-resolved reverberation response of the H$β$ broad emission line in nine Seyfert 1 galaxies from the Lick Active Galactic Nucleus (AGN) Monitoring Project 2016 sample, drawing inferences on the geometry and structure of the low-ionization broad-line region (BLR) and the mass of the central supermassive black hole. Overall, we find that the H$β$ BLR is generally a thick disk viewed at low to moderate inclination angles. We combine our sample with prior studies and investigate line-profile shape dependence, such as $log_{10}(FWHM/\sigma)$, on BLR structure and kinematics and search for any BLR luminosity-dependent trends. We find marginal evidence for an anticorrelation between the profile shape of the broad H$β$ emission line and the Eddington ratio, when using the rms spectrum. However, we do not find any luminosity-dependent trends, and conclude that AGNs have diverse BLR structure and kinematics, consistent with the hypothesis of transient AGN/BLR conditions rather than systematic trends., Published by Univ., Chicago, Ill. [u.a.]

We carried out spectroscopic monitoring of 21 low-redshift Seyfert 1 galaxies using the Kast double spectrograph on the 3-m Shane telescope at Lick Observatory from April 2016 to May 2017. Targeting active galactic nuclei (AGN) with luminosities of ��L�� (5100 ��) = 10^44 erg/s and predicted H�� lags of 20-30 days or black hole masses of 10^7-10^8.5 Msun, our campaign probes luminosity-dependent trends in broad-line region (BLR) structure and dynamics as well as to improve calibrations for single-epoch estimates of quasar black hole masses. Here we present the first results from the campaign, including H�� emission-line light curves, integrated H�� lag times (8-30 days) measured against V-band continuum light curves, velocity-resolved reverberation lags, line widths of the broad H�� components, and virial black hole mass estimates (10^7.1-10^8.1 Msun). Our results add significantly to the number of existing velocity-resolved lag measurements and reveal a diversity of BLR gas kinematics at moderately high AGN luminosities. AGN continuum luminosity appears not to be correlated with the type of kinematics that its BLR gas may exhibit. Follow-up direct modeling of this dataset will elucidate the detailed kinematics and provide robust dynamical black hole masses for several objects in this sample., 34 pages, 14 figures, accepted for publication in ApJ

PURPOSE To evaluate the ability of contrast-enhanced MRI with SHU 555 A to provide additional information for characterization of focal liver tumors compared with non-enhanced MRI and multislice spiral CT. MATERIALS AND METHODS In a prospective manner the images of 45 patients who underwent multislice spiral CT, unenhanced MRI alone and unenhanced and SHU 555 A-enhanced MRI including dynamic imaging at a field strength of 1.0 T were analyzed in a blinded reading. The readers had to determine on a scale from 1 to 5 whether a tumor was benign or malignant. Furthermore, the readers had to give a definitive diagnosis for each lesion. A true cut needle biopsy served as gold standard against which all imaging procedures were compared. RESULTS The sensitivity for differentiation malignant vs. benign lesion was 77 % with spiral CT, 72 % with unenhanced MRI and 94 % with SHU 555 A-enhanced MRI, respectively (p < 0.05). The specificity for spiral CT was 73 %, for unenhanced MRI 83 % and for contrast-enhanced MRI 83 %, respectively (n. s.). Compared with the histopathologic results, the correct diagnosis was made with spiral CT in 25/45 (56 %), unenhanced MRI in 16/45 (36 %) and contrast-enhanced MRI in 32/45 (71 %) of the patients (p < 0.05). For the subgroup of patients with liver cirrhosis, the correct diagnosis was established with spiral CT in 16/23 (70 %), unenhanced MRI in 9/23 (39 %) and contrast-enhanced MRI in 19/23 (83 %) of the patients (p < 0.05). CONCLUSION Contrast-enhanced MRI with SHU 555 A has the ability to improve the differential diagnosis of focal liver tumors compared with unenhanced MRI and multislice spiral CT.