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Reversal learning measures the ability to form flexible associations between choice outcomes with stimuli and actions that precede them. This type of learning is thought to rely on several cortical and subcortical areas, including the highly interconnected orbitofrontal cortex (OFC) and basolateral amygdala (BLA), and is often impaired in various neuropsychiatric and substance use disorders. However, the unique contributions of these regions to stimulus- and action-based reversal learning have not been systematically compared using a chemogenetic approach particularly before and after the first reversal that introduces new uncertainty. Here, we examined the roles of ventrolateral OFC (vlOFC) and BLA during reversal learning. Male and female rats were prepared with inhibitory designer receptors exclusively activated by designer drugs targeting projection neurons in these regions and tested on a series of deterministic and probabilistic reversals during which they learned about stimulus identity or side (left or right) associated with different reward probabilities. Using a counterbalanced within-subject design, we inhibited these regions prior to reversal sessions. We assessed initial and pre-/post-reversal changes in performance to measure learning and adjustments to reversals, respectively. We found that inhibition of the ventrolateral orbitofrontal cortex (vlOFC), but not BLA, eliminated adjustments to stimulus-based reversals. Inhibition of BLA, but not vlOFC, selectively impaired action-based probabilistic reversal learning, leaving deterministic reversal learning intact. vlOFC exhibited a sex-dependent role in early adjustment to action-based reversals, but not in overall learning. These results reveal dissociable roles for BLA and vlOFC in flexible learning and highlight a more crucial role for BLA in learning meaningful changes in the reward environment.

Hyun Jung Lee,1 Ji Seon Chae,2 Sang-Mee An,2 Hye-Won Oh,1 Youn Jin Kim,1 Jae Hee Woo1 1Department of Anesthesiology and Pain Medicine, College of Medicine, Ewha Womans University, Seoul, South Korea; 2Department of Anesthesiology and Pain Medicine, Ewha Womans University Seoul Hospital, Seoul, South KoreaCorrespondence: Jae Hee Woo, Department of Anesthesiology and Pain Medicine, College of Medicine, Ewha Womans University, 260 Gonghangdaero, Gangseo-gu, Seoul, 07804, South Korea, Tel +82-2-6986-4300, Fax +82-2-6986-4960, Email jheewoo@ewha.ac.krPurpose: Monitoring end-tidal carbon dioxide partial pressure (PETCO2) is a noninvasive, continuous method, but its accuracy is reduced by prolonged capnoperitoneum and the steep Trendelenburg position in robot-assisted radical prostatectomy (RARP). Transcutaneous carbon dioxide partial pressure (PTCCO2) monitoring, which is not affected by ventilator–perfusion mismatch, has been suggested as a suitable alternative. We compared the agreement of noninvasive measurements with the arterial carbon dioxide partial pressure (PaCO2) over a long period of capnoperitoneum, and investigated its sensitivity and predictive power for detecting hypercapnia.Patients and Methods: The patients who underwent RARP were enrolled in this study prospectively. Intraoperative measurements of PETCO2, PTCCO2, and PaCO2 were analyzed. The primary outcome was the agreement of noninvasive monitoring with PaCO2 during prolonged capnoperitoneum. Bias and precision between noninvasive measurements and PaCO2 were assessed using Bland–Altman analysis. The bias and mean absolute difference were compared using a two-tailed Wilcoxon signed-rank test for pairs. The secondary outcome was the sensitivity and predictive power for detecting hypercapnia. To assess this, the Yates corrected chi-square test and the area under the receiver operating characteristic curve were used.Results: The study analyzed 219 datasets from 46 patients. Compared with PETCO2, PTCCO2 had lower bias, greater precision, and better agreement with PaCO2 throughout the RARP. The mean absolute difference in PETCO2 and PaCO2 was larger than that of PTCCO2 and PaCO2, and continued to exceed the clinically acceptable range of 5 mmHg after 1 hour of capnoperitoneum. The sensitivity during capnoperitoneum and overall predictive power of PTCCO2 for detecting hypercapnia were significantly higher than those of PETCO2, suggesting a greater contribution to ventilator adjustment, to treat hypercapnia.Conclusion: PTCCO2 monitoring measured PaCO2 more accurately than PETCO2 monitoring during RARP requiring prolonged capnoperitoneum and a steep Trendelenburg position. PTCCO2 monitoring also provides more sensitive measurements for ventilator adjustment and detects hypercapnia more effectively than PETCO2 monitoring.Keywords: intraoperative carbon dioxide monitoring, capnoperitoneum, robotic surgery, end-tidal carbon dioxide monitoring, general anesthesia

We present models of the Hβ-emitting broad-line region (BLR) in seven Seyfert 1 galaxies from the Lick AGN Monitoring Project 2011 sample, drawing inferences on the BLR structure and dynamics as well as the mass of the central supermassive black hole. We find that the BLR is generally a thick disk, viewed close to face-on, with preferential emission back toward the ionizing source. The dynamics in our sample range from near-circular elliptical orbits to inflowing or outflowing trajectories. We measure black hole masses of for PG 1310-108, for Mrk 50, for Mrk 141, for Mrk 279, for Mrk 1511, for NGC 4593, and for Zw 229-015. We use these black hole mass measurements along with cross-correlation time lags and line widths to recover the scale factor f used in traditional reverberation mapping measurements. Combining our results with other studies that use this modeling technique, which brings our sample size to 16, we calculate a scale factor that can be used for measuring black hole masses in other reverberation mapping campaigns. When using the root-mean-square (rms) spectrum and using the line dispersion to measure the line width, we find pred = 0.57 0.19. Finally, we search for correlations between f and other AGN and BLR parameters and find marginal evidence that f is correlated with M BH and the BLR inclination angle, but no significant evidence of a correlation with the AGN luminosity or Eddington ratio.

© Author(s) 2018. Accurate and consistent monitoring of anthropogenic combustion is imperative because of its significant health and environmental impacts, especially at city-to-regional scale. Here, we assess the performance of the Copernicus Atmosphere Monitoring Service (CAMS) global prediction system using measurements from aircraft, ground sites, and ships during the Korea-United States Air Quality (KORUS-AQ) field study in May to June 2016. Our evaluation focuses on CAMS CO and CO2 analyses as well as two higher-resolution forecasts (16 and 9km horizontal resolution) to assess their capability in predicting combustion signatures over east Asia. Our results show a slight overestimation of CAMS CO2 with a mean bias against airborne CO2 measurements of 2.2, 0.7, and 0.3ppmv for 16 and 9km CO2 forecasts, and analyses, respectively. The positive CO2 mean bias in the 16km forecast appears to be consistent across the vertical profile of the measurements. In contrast, we find a moderate underestimation of CAMS CO with an overall bias against airborne CO measurements of -19.2 (16km), -16.7 (9km), and -20.7ppbv (analysis). This negative CO mean bias is mostly seen below 750hPa for all three forecast/analysis configurations. Despite these biases, CAMS shows a remarkable agreement with observed enhancement ratios of CO with CO2 over the Seoul metropolitan area and over the West (Yellow) Sea, where east Asian outflows were sampled during the study period. More efficient combustion is observed over Seoul (dCO dCO2 Combining double low line 9ppbvppmv-1) compared to the West Sea (dCO dCO2 Combining double low line 28ppbvppmv-1). This "combustion signature contrast" is consistent with previous studies in these two regions. CAMS captured this difference in enhancement ratios (Seoul: 8-12ppbvppmv-1, the West Sea: ∼ 30ppbvppmv-1) regardless of forecast/analysis configurations. The correlation of CAMS CO bias with CO2 bias is relatively high over these two regions (Seoul: 0.64-0.90, the West Sea: ∼ 0.80) suggesting that the contrast captured by CAMS may be dominated by anthropogenic emission ratios used in CAMS. However, CAMS shows poorer performance in terms of capturing local-to-urban CO and CO2 variability. Along with measurements at ground sites over the Korean Peninsula, CAMS produces too high CO and CO2 concentrations at the surface with steeper vertical gradients (∼ 0.4ppmvhPa-1 for CO2 and 3.5ppbvhPa-1 for CO) in the morning samples than observed (∼ 0.25ppmvhPa-1 for CO2 and 1.7ppbvhPa-1 for CO), suggesting weaker boundary layer mixing in the model. Lastly, we find that the combination of CO analyses (i.e., improved initial condition) and use of finer resolution (9km vs. 16km) generally produces better forecasts.

The Seyfert 1 galaxy Arp 151 was monitored as part of three reverberation mapping campaigns spanning 2008-2015. We present modeling of these velocity-resolved reverberation mapping data sets using a geometric and dynamical model for the broad-line region (BLR). By modeling each of the three data sets independently, we infer the evolution of the BLR structure in Arp 151 over a total of 7 yr and constrain the systematic uncertainties in nonvarying parameters such as the black hole mass. We find that the BLR geometry of a thick disk viewed close to face-on is stable over this time, although the size of the BLR grows by a factor of ∼2. The dynamics of the BLR are dominated by inflow, and the inferred black hole mass is consistent for the three data sets, despite the increase in BLR size. Combining the inference for the three data sets yields a black hole mass and statistical uncertainty of log10(/) = with a standard deviation in individual measurements of 0.13 dex.

We provide an updated calibration of C iv broad emission line-based single-epoch (SE) black hole (BH) mass estimators for active galactic nuclei (AGNs) using new data for six reverberation-mapped AGNs at redshift with BH masses (bolometric luminosities) in the range106.5-107.5 M⊙(1041.7-1043.8 erg s-1). New rest-frame UV-to-optical spectra covering 1150-5700 Å for the six AGNs were obtained with the Hubble Space Telescope (HST). Multicomponent spectral decompositions of the HST spectra were used to measure SE emission-line widths for the C iv, Mg ii, and Hβ lines, as well as continuum luminosities in the spectral region around each line. We combine the new data with similar measurements for a previous archival sample of 25 AGNs to derive the most consistent and accurate calibrations of the C iv-based SE BH mass estimators against the Hβ reverberation-based masses, using three different measures of broad-line width: full width at half maximum (FWHM), line dispersion (σline), and mean absolute deviation (MAD). The newly expanded sample at redshift z = 0.005-0.234 covers a dynamic range in BH mass (bolometric luminosity) of log MBH M⊙ = 6.5-9.1(log Lbol/erg s-1 = 41.7-46.9), and we derive the new C iv-based mass estimators using a Bayesian linear regression analysis over this range. We generally recommend the use of or MAD rather than FWHM to obtain a less biased velocity measurement of the C iv emission line, because its narrow-line component contribution is difficult to decompose from the broad-line profile.

We conduct a multiwavelength continuum variability study of the Seyfert 1 galaxy NGC 5548 to investigate the temperature structure of its accretion disk. The 19 overlapping continuum light curves (1158 A oto 9157 A o) combine simultaneous Hubble Space Telescope, Swift, and ground-based observations over a 180 day period from 2014 January to July. Light-curve variability is interpreted as the reverberation response of the accretion disk to irradiation by a central time-varying point source. Our model yields the disk inclination i = 36° ±10° temperature T1 = 44 ±6 ) × 10 3 K at 1 light day from the black hole, and a temperatureradius slope (T ∞r-a) of a = 0.99 ±0.03. We also infer the driving light curve and find that it correlates poorly with both the hard and soft X-ray light curves, suggesting that the X-rays alone may not drive the ultraviolet and optical variability over the observing period. We also decompose the light curves into bright, faint, and mean accretion-disk spectra. These spectra lie below that expected for a standard blackbody accretion disk accreting at L LEdd = 0.1.

Hyun Jung Lee,1 Jae Hee Woo,2 Sooyoung Cho,3 Hye-Won Oh,1 Hyunyoung Joo,3 Hee Jung Baik2 1Department of Anesthesiology and Pain Medicine, Ewha Womans University Seoul Hospital, Seoul, South Korea; 2Department of Anesthesiology and Pain Medicine, College of Medicine, Ewha Womans University, Seoul, South Korea; 3Department of Anesthesiology and Pain Medicine, Ewha Womans University Mokdong Hospital, Seoul, South KoreaCorrespondence: Hee Jung BaikDepartment of Anesthesiology and Pain Medicine, College of Medicine, Ewha Womans University, 25, Magokdong-ro 2-gil, Gangseo-gu, Seoul 07804, Republic of KoreaTel +82-2-2650-2868Fax +82-2-2655-2924Email baikhj@ewha.ac.krPurpose: In pediatric patients, the most common reason for delaying surgical intervention is an upper respiratory tract infection (URI). To date, there has been no consensus regarding the optimal timeframe for deferring surgery in children with URI. We conducted this study to evaluate whether a URI symptom-free period and other risk factors affect the incidence of perioperative respiratory adverse events (RAEs).Patients and Methods: The study population included 267 pediatric patients (aged 0 to 13 years) with a recent URI episode who underwent surgery under general anesthesia. Following a retrospective review of medical records, several risk factors including a URI symptom-free period for intra- and postoperative RAEs were analyzed using univariate and multivariate logistic regression analyses.Results: RAEs occurred in 23 of 267 patients (8.6%). Univariate analysis revealed that abnormal preoperative chest images (odds ratio [OR], 7.48; 95% confidence interval [CI], 2.46– 22.68, p < 0.001) and emergency operations (OR, 2.84; 95% CI, 1.03– 7.81, p = 0.04) were associated with RAEs. Four variables (abnormal preoperative chest images, emergency operations, age under 1 year and symptom-free period of 7– 13 days) with a significance of < 0.20 in the univariate logistic regression analysis were selected as candidate risk factors for the multivariate model. Among the four variables, abnormalities in preoperative chest images (OR, 7.60; 95% CI, 2.28– 25.3, p = 0.001) and a symptom-free period of 7– 13 days (OR, 0.13; 95% CI, 0.02– 0.88, p = 0.04) were independently associated with RAEs in multivariate logistic regression analysis.Conclusion: For pediatric patients who require surgery and have a recent history of URI, procedures should be performed after a URI symptom-free period of at least 1– 2 weeks. Confirming the absence of abnormalities in preoperative chest images can reduce the incidence of perioperative RAEs.Keywords: pediatric, general anesthesia, upper respiratory tract infection, respiratory adverse event

During an intensive Hubble Space Telescope (HST) Cosmic Origins Spectrograph (COS) UV monitoring campaign of the Seyfert 1 galaxy NGC 5548 performed from 2014 February to July, the normally highly correlated far UV continuum and broad emission line variations decorrelated for ∼60-70 days, starting ∼75 days after the first HST/COS observation. Following this anomalous state, the flux and variability of the broad emission lines returned to a more normal state. This transient behavior, characterized by significant deficits in flux and equivalent width of the strong broad UV emission lines, is the first of its kind to be unambiguously identified in an active galactic nucleus reverberation mapping campaign. The largest corresponding emission line flux deficits occurred for the high ionization, collisionally excited lines C iv and Si iv(+O iv]), and also He ii(+O iii]), while the anomaly in Lywas substantially smaller. This pattern of behavior indicates a depletion in the flux of photons with relative to those near 13.6 eV. We suggest two plausible mechanisms for the observed behavior: (i) temporary obscuration of the ionizing continuum incident upon broad line region (BLR) clouds by a moving veil of material lying between the inner accretion disk and inner (BLR), perhaps resulting from an episodic ejection of material from the disk, or (ii) a temporary change in the intrinsic ionizing continuum spectral energy distribution resulting in a deficit of ionizing photons with energies >54 eV, possibly due to a transient restructuring of the Comptonizing atmosphere above the disk. Current evidence appears to favor the latter explanation.

We present ground-based optical photometric monitoring data for NGC 5548, part of an extended multiwavelength reverberation mapping campaign. The light curves have nearly daily cadence from 2014 January to July in nine filters (BVRI and ugriz). Combined with ultraviolet data from the Hubble Space Telescope and Swift, we confirm significant time delays between the continuum bands as a function of wavelength, extending the wavelength coverage from 1158 Å to the z band (∼9160 Å). We find that the lags at wavelengths longer than the V band are equal to or greater than the lags of high-ionization-state emission lines (such as He ii and λ1640 and λ4686), suggesting that the continuum-emitting source is of a physical size comparable to the inner broad-line region (BLR). The trend of lag with wavelength is broadly consistent with the prediction for continuum reprocessing by an accretion disk with τ ∝ λ 4 . However, the lags also imply a disk radius that is 3 times larger than the prediction from standard thin-disk theory, assuming that the bolometric luminosity is 10% of the Eddington luminosity (L = 0.1 L Edd ). Using optical spectra from the Large Binocular Telescope, we estimate the bias of the interband continuum lags due to BLR emission observed in the filters. We find that the bias for filters with high levels of BLR contamination (∼20%) can be important for the shortest continuum lags and likely has a significant impact on the u and U bands owing to Balmer continuum emission.

We create a baseline of the black hole (BH) mass (MBH).stellar-velocity dispersion () relation for active galaxies, using a sample of 66 local (0.02 < z < 0.09) Seyfert-1 galaxies, selected from the Sloan Digital Sky Survey (SDSS). Analysis of SDSS images yields AGN luminosities free of host-galaxy contamination, and morphological classification. 51/66 galaxies have spiral morphology. Out of these, 28 bulges have Sersic index n < 2 and are considered candidate pseudo-bulges, with eight being definite pseudo-bulges based on multiple classification criteria met. Only 4/66 galaxies show signs of interaction/merging. High signal-to-noise ratio Keck spectra provide the width of the broad Hβ emission line free of Fe II emission and stellar absorption. AGN luminosity and Hβ line widths are used to estimate MBH. The Keck-based spatially resolved kinematics is used to determine stellar-velocity dispersion within the spheroid effective radius (σspat,reff). We find that σ can vary on average by up to 40% across definitions commonly used in the literature, emphasizing the importance of using selfconsistent definitions in comparisons and evolutionary studies. The MBH-σ relation for our Seyfert-1 galaxy sample has the same intercept and scatter as that of reverberation-mapped AGNs as well as that of quiescent galaxies, consistent with the hypothesis that our single epoch MBH estimator and sample selection function do not introduce significant biases. Barred galaxies, merging galaxies, and those hosting pseudo-bulges do not represent outliers in the MBH-σ relation. This is in contrast with previous work, although no firm conclusion can be drawn on this matter due to the small sample size and limited resolution of the SDSS images.

In the Spring of 2011 we carried out a 2.5 month reverberation mapping campaign using the 3 m Shane telescope at Lick Observatory, monitoring 15 low-redshift Seyfert 1 galaxies. This paper describes the observations, reductions and measurements, and data products from the spectroscopic campaign. The reduced spectra were fitted with a multicomponent model in order to isolate the contributions of various continuum and emission-line components. We present light curves of broad emission lines and the active galactic nucleus (AGN) continuum, and measurements of the broad Hβ line widths in mean and rms spectra. For the most highly variable AGNs we also measured broad Hβ line widths and velocity centroids from the nightly spectra. In four AGNs exhibiting the highest variability amplitudes, we detect anticorrelations between broad Hβ width and luminosity, demonstrating that the broad-line region "breathes" on short timescales of days to weeks in response to continuum variations. We also find that broad Hβ velocity centroids can undergo substantial changes in response to continuum variations; in NGC 4593, the broad Hβ velocity shifted by ∼250 km s-1 over a 1 month period. This reverberation-induced velocity shift effect is likely to contribute a significant source of confusion noise to binary black hole searches that use multi-epoch quasar spectroscopy to detect binary orbital motion. We also present results from simulations that examine biases that can occur in measurement of broad-line widths from rms spectra due to the contributions of continuum variations and photon-counting noise.

We investigate the cosmic evolution of the black hole (BH) mass-bulge luminosity relation using a sample of 52 active galaxies at z ∼ 0.36 and z ∼ 0.57 in the BH mass range of 107.4-109.1 M o. By consistently applying multicomponent spectral and structural decomposition to high-quality Keck spectra and high-resolution Hubble Space Telescope images, BH masses (M oBH) are estimated using the Hβ broad emission line combined with the 5100 Å nuclear luminosity, and bulge luminosities (L bul) are derived from surface photometry. Comparing the resulting M oBH-L bul relation to local active galaxies and taking into account selection effects, we find evolution of the form M oBH-L bul(1 + z)γ with γ = 1.8 ± 0.7, consistent with BH growth preceding that of the host galaxies. Including an additional sample of 27 active galaxies with 0.5 < z < 1.9 taken from the literature and measured in a consistent way, we obtain γ = 0.9 ± 0.7 for the M oBH-L bul relation and γ = 0.4 ± 0.5 for the M oBH-total host galaxy luminosity (L host) relation. The results strengthen the findings from our previous studies and provide additional evidence for host galaxy bulge growth being dominated by disk-to-bulge transformation via minor mergers and/or disk instabilities.

We use Chandra data to study the incidence and properties of active galactic nuclei (AGNs) in 16 intermediate redshift (0.5 < z < 1.1) X-ray-selected galaxy groups in the Chandra Deep Field-South. We measure an AGN fraction of at , approximately a factor of two higher than the AGN fraction found for rich clusters at comparable redshift. This extends the trend found at low redshift for groups to have higher AGN fractions than clusters. Our estimate of the AGN fraction is also more than a factor of three higher than that of low redshift X-ray-selected groups. Using optical spectra from various surveys, we also constrain the properties of emission-line selected AGNs in these groups. In contrast to the large population of X-ray AGNs (N(L X, H > 1041 erg s-1) = 25), we find only four emission-line AGNs, three of which are also X-ray bright. Furthermore, most of the X-ray AGNs in our groups are optically dull (i.e., lack strong emission-lines), similar to those found in low redshift X-ray groups and clusters of galaxies. This contrasts with the AGN population found in low redshift optically selected groups which are dominated by emission-line AGNs. The differences between the optically and X-ray-selected AGNs populations in groups are consistent with a scenario where most AGNs in the densest environments are currently in a low accretion state. © 2014. The American Astronomical Society. All rights reserved..

We use a 3-D regional atmospheric chemistry transport model (WRF-Chem) to examine ozone dry deposition in East Asia, which is an important but uncertain research area because of insufficient observation and numerical studies focusing on East Asia. Here we compare two widely used dry deposition parameterization schemes, the Wesely and M3DRY schemes, which are used in the WRF-Chem and Community Multiscale Air Quality (CMAQ) models, respectively. Simulated ozone dry deposition velocities with the two schemes under identical meteorological conditions show considerable differences (a factor of 2) owing to surface resistance parameterization discrepancies. Resulting ozone concentrations differ by up to 10 ppbv for a monthly mean in May when the peak ozone typically occurs in East Asia. An evaluation of the simulated dry deposition velocities shows that the Wesely scheme calculates values with more pronounced diurnal variation than the M3DRY and results in a good agreement with the observations. However, we find significant changes in simulated ozone concentrations using the Wesely scheme but with different surface type data sets, indicating the high sensitivity of ozone deposition calculations to the input data. The need is high for observations to constrain the dry deposition parameterization and its input data to improve the use of air quality models for East Asia.

We present dynamical modelling of the broad-line region (BLR) for a sample of five Seyfert 1 galaxies using reverberation mapping data taken by the Lick AGN Monitoring Project in 2008. By modelling the AGN continuum light curve and Hβ line profiles directly, we are able to constrain the geometry and kinematics of the BLR and make a measurement of the black hole mass that does not depend upon the virial factor, f, needed in traditional reverberation mapping analysis. We find that the geometry of the BLR is generally a thick disc viewed close to face-on. While the Hβ emission is found to come preferentially from the far side of the BLR, the mean size of the BLR is consistent with the lags measured with crosscorrelation analysis. The BLR kinematics are found to be consistent with either inflowing motions or elliptical orbits, often with some combination of the two. We measure black hole masses of log10(MBH/M⊙) = 6.62-0.13+0.10 for Arp 151, 7.42-0.27+0.26 for Mrk 1310, 7.59-0.21+0.24 for NGC 5548, 6.37-0.16+0.21 for NGC 6814, and 6.99-0.25+0.32 for SBS 1116+583A. The f factors measured individually for each AGN are found to correlate with inclination angle, although not with MBH, L5100, or FWHM/s of the emission line profile.

Shukho Kim,1 Jung Hwa Woo,1 Nayeong Kim,1 Mi Hyun Kim,1 Se Yeon Kim,1 Joo Hee Son,1 Dong Chan Moon,2 Suk-Kyung Lim,2 Minsang Shin,1 Je Chul Lee1 1Department of Microbiology, School of Medicine, Kyungpook National University, Daegu, Republic of Korea; 2Bacterial Disease Division, Animal and Plant Quarantine Agency, Gimcheon-si, Gyeongsangbuk-do, Republic of KoreaCorrespondence: Je Chul LeeDepartment of Microbiology, School of Medicine, Kyungpook National University, 680 Gukchaebosang-ro, Jung-gu, Daegu 41944, Republic of KoreaTel +82-53-420-4844Fax +82-53-427-5664Email leejc@knu.ac.krPurpose: Colistin resistance in gram-negative bacteria from humans and livestock has been increasingly reported worldwide. The aim of this study was to investigate the underlying mechanisms of chromosome-mediated colistin resistance in Escherichia coli isolates from livestock in Korea.Materials and methods: Thirty mcr-1-negative isolates were selected from a collection of colistin-resistant E. coli isolates collected from livestock in 2005 and 2015 in Korea. Amino acid alterations in PmrAB, PhoPQ, MgrB, and PmrD were investigated. Colistin-resistant derivatives were produced by serial passage of colistin-susceptible E. coli isolates in colistin-containing media.Results: Thirty colistin-resistant mcr-negative E. coli isolates were classified into 26 sequence types. Twenty-two isolates carried diverse amino acid alterations in PmrB, PhoP, PhoQ, MgrB, and/or PmrD, whereas no mutation in any of these genes was found in the remaining eight isolates. Sixteen out of the 22 isolates shared a total of nine polymorphic positions that were found in colistin-susceptible E. coli strains. Colistin-resistant derivatives from two colistin-susceptible isolates showed the same genetic alterations that were observed in colistin-resistant clinical isolates.Conclusion: Our results suggest that the mechanism underlying chromosome-mediated colistin resistance remain to be discovered in E. coli. Selective pressure of colistin in vitro induced the same genetic mutations associated with colistin resistance in vivo. Efforts to reduce colistin consumption in livestock should be redoubled, to prevent the occurrence of colistin-resistant E. coli strains.Keywords: colistin resistance, two-component system, livestock, genetic mutation, mcr gene

We investigate the dependence of the normalization of the high-frequency part of the X-ray and optical power spectral densities (PSDs) on black hole mass for a sample of 39 active galactic nuclei (AGNs) with black hole masses estimated from reverberation mapping or dynamical modeling. We obtained new Swift observations of PG 1426+015, which has the largest estimated black hole mass of the AGNs in our sample. We develop a novel statistical method to estimate the PSD from a light curve of photon counts with arbitrary sampling, eliminating the need to bin a light curve to achieve Gaussian statistics, and we use this technique to estimate the X-ray variability parameters for the faint AGNs in our sample. We find that the normalization of the high-frequency X-ray PSD is inversely proportional to black hole mass. We discuss how to use this scaling relationship to obtain black hole mass estimates from the short timescale X-ray variability amplitude with precision ∼0.38 dex. The amplitude of optical variability on timescales of days is also anticorrelated with black hole mass, but with larger scatter. Instead, the optical variability amplitude exhibits the strongest anticorrelation with luminosity. We conclude with a discussion of the implications of our results for estimating black hole mass from the amplitude of AGN variability. © 2013. The American Astronomical Society. All rights reserved.

The prominent broad Fe II emission blends in the spectra of active galactic nuclei have been shown to vary in response to continuum variations, but past attempts to measure the reverberation lag time of the optical Fe II lines have met with only limited success. Here we report the detection of Fe II reverberation in two Seyfert 1 galaxies, NGC 4593 and Mrk 1511, based on data from a program carried out at Lick Observatory in Spring 2011. Light curves for emission lines including Hβ and Fe II were measured by applying a fitting routine to decompose the spectra into several continuum and emission-line components, and we use cross-correlation techniques to determine the reverberation lags of the emission lines relative to V-band light curves. In both cases, the measured lag (τcen) of Fe II is longer than that of Hβ, although the inferred lags are somewhat sensitive to the choice of Fe II template used in the fit. For spectral decompositions done using the Fe II template of Véron-Cetty et al., we find τcen (Fe II)/τcen (Hβ) = 1.9 ± 0.6 in NGC 4593 and 1.5 ± 0.3 in Mrk 1511. The detection of highly correlated variations between Fe II and continuum emission demonstrates that the Fe II emission in these galaxies originates in photoionized gas, located predominantly in the outer portion of the broad-line region. © 2013. The American Astronomical Society. All rights reserved.

We present an updated and revised analysis of the relationship between the Hβ broad-line region (BLR) radius and the luminosity of the active galactic nucleus (AGN). Specifically, we have carried out two-dimensional surface brightness decompositions of the host galaxies of nine new AGNs imaged with the Hubble Space Telescope Wide Field Camera 3. The surface brightness decompositions allow us to create "AGN-free" images of the galaxies, from which we measure the starlight contribution to the optical luminosity measured through the ground-based spectroscopic aperture. We also incorporate 20 new reverberation-mapping measurements of the Hβ time lag, which is assumed to yield the average Hβ BLR radius. The final sample includes 41 AGNs covering four orders of magnitude in luminosity. The additions and updates incorporated here primarily affect the low-luminosity end of the R BLR-L relationship. The best fit to the relationship using a Bayesian analysis finds a slope of , consistent with previous work and with simple photoionization arguments. Only two AGNs appear to be outliers from the relationship, but both of them have monitoring light curves that raise doubt regarding the accuracy of their reported time lags. The scatter around the relationship is found to be 0.19 ± 0.02 dex, but would be decreased to 0.13 dex by the removal of these two suspect measurements. A large fraction of the remaining scatter in the relationship is likely due to the inaccurate distances to the AGN host galaxies. Our results help support the possibility that the RBLR-L relationship could potentially be used to turn the BLRs of AGNs into standardizable candles. This would allow the cosmological expansion of the universe to be probed by a separate population of objects, and over a larger range of redshifts. © 2013. The American Astronomical Society. All rights reserved.

We present dynamical modeling of the broad-line region (BLR) in the Seyfert 1 galaxy Mrk 50 using reverberation mapping data taken as part of the Lick AGN Monitoring Project (LAMP) 2011. We model the reverberation mapping data directly, constraining the geometry and kinematics of the BLR, as well as deriving a black hole mass estimate that does not depend on a normalizing factor or virial coefficient. We find that the geometry of the BLR in Mrk 50 is a nearly face-on thick disk, with a mean radius of 9.6+1.2-0.9 light days, a width of the BLR of 6.9+1.2-1.1 light days, and a disk opening angle of 25 ± 10 deg above the plane. We also constrain the inclination angle to be 9+7-5 deg, close to face-on. Finally, the black hole mass of Mrk 50 is inferred to be log10(M BH/M = 7.57+0.44-0.27. By comparison to the virial black hole mass estimate from traditional reverberation mapping analysis, we find the normalizing constant (virial coefficient) to be log10 f = 0.78+0.44-0.27, consistent with the commonly adopted mean value of 0.74 based on aligning the M BH-σ* relation for active galactic nuclei and quiescent galaxies. While our dynamical model includes the possibility of a net inflow or outflow in the BLR, we cannot distinguish between these two scenarios. © 2012. The American Astronomical Society. All rights reserved..

We investigate the calibration and uncertainties of black hole (BH) mass estimates based on the single-epoch (SE) method, using homogeneous and high-quality multi-epoch spectra obtained by the Lick Active Galactic Nucleus (AGN) Monitoring Project for nine local Seyfert 1 galaxies with BH masses

The Lick AGN Monitoring Project 2011 observing campaign was carried out over the course of 11 weeks in spring 2011. Here we present the first results from this program, a measurement of the broad-line reverberation lag in the Seyfert 1 galaxy Mrk50. Combining our data with supplemental observations obtained prior to the start of the main observing campaign, our data set covers a total duration of 4.5 months. During this time, Mrk50 was highly variable, exhibiting a maximum variability amplitude of a factor of 4 in the U-band continuum and a factor of ∼2 in the Hβ line. Using standard cross-correlation techniques, we find that Hβ and Hγ lag the V-band continuum by τcen = 10.64+0.82- 0.93 and 8.43+1.30- 1.28days, respectively, while the lag of He II λ4686 is unresolved. The Hβ line exhibits a symmetric velocity-resolved reverberation signature with shorter lags in the high-velocity wings than in the line core, consistent with an origin in a broad-line region (BLR) dominated by orbital motion rather than infall or outflow. Assuming a virial normalization factor of f = 5.25, the virial estimate of the black hole mass is (3.2 ± 0.5) × 107 M ⊙. These observations demonstrate that Mrk50 is among the most promising nearby active galaxies for detailed investigations of BLR structure and dynamics. © 2011. The American Astronomical Society. All rights reserved.

We combine Hubble Space Telescope images from the Great Observatories Origins Deep Survey with archival Very Large Telescope and Keck spectra of a sample of 11 X-ray-selected broad-line active galactic nuclei in the redshift range 1 < z < 2 to study the black-hole-mass-stellar-mass relation out to a look-back time of 10Gyr. Stellar masses of the spheroidal component (M sph,*) are derived from multi-filter surface photometry. Black hole masses (MBH) are estimated from the width of the broad MgII emission line and the 3000 Å nuclear luminosity. Comparing with a uniformly measured local sample and taking into account selection effects, we find evolution in the form MBH/Msph,*(1 + z) 1.96 ± 0.55, in agreement with our earlier studies based on spheroid luminosity. However, this result is more accurate because it does not require a correction for luminosity evolution and therefore avoids the related and dominant systematic uncertainty. We also measure total stellar masses (Mhost,*). Combining our sample with data from the literature, we find M BH/Mhost,*(1 + z) 1.15 ±0.15, consistent with the hypothesis that black holes (in the range MBH ∼108-9 M⊙) pre-date the formation of their host galaxies. Roughly, one-third of our objects reside in spiral galaxies; none of the host galaxies reveal signs of interaction or major merger activity. Combined with the slower evolution in host stellar masses compared to spheroid stellar masses, our results indicate that secular evolution or minor mergers play a non-negligible role in growing both BHs and spheroids. © 2011. The American Astronomical Society. All rights reserved.

Supermassive black holes are believed to be ubiquitous at the centers of galaxies. Measuring their masses is extremely challenging yet essential for understanding their role in the formation and evolution of cosmic structure. We present a direct measurement of the mass of a black hole in an active galactic nucleus (Arp 151) based on the motion of the gas responsible for the broad emission lines. By analyzing and modeling spectroscopic and photometric time series, we find that the gas is well described by a disk or torus with an average radius of 3.99 1.25 light days and an opening angle of 68.9 +21.4-17.2 deg, viewed at an inclination angle of 67.8 7.8 deg (that is, closer to face-on than edge-on). The black hole mass is inferred to be 106.51 0.28 M. The method is fully general and can be used to determine the masses of black holes at arbitrary distances, enabling studies of their evolution over cosmic time. © 2011. The American Astronomical Society. All rights reserved.

The Seyfert 1 galaxy Zw 229-015 is among the brightest active galaxies being monitored by the Kepler mission. In order to determine the black hole mass in Zw 229-015 from Hβ reverberation mapping, we have carried out nightly observations with the Kast Spectrograph at the Lick 3 m telescope during the dark runs from 2010 June through December, obtaining 54 spectroscopic observations in total. We have also obtained nightly V-band imaging with the Katzman Automatic Imaging Telescope at Lick Observatory and with the 0.9 m telescope at the Brigham Young University West Mountain Observatory over the same period. We detect strong variability in the source, which exhibited more than a factor of two change in broad Hβ flux. From cross-correlation measurements, we find that the Hβ light curve has a rest-frame lag of 3.86+0.69-0.90 days with respect to the V-band continuum variations. We also measure reverberation lags for Hα and Hγ and find an upper limit to the Hδ lag. Combining the Hβ lag measurement with a broad Hβ width of σline = 1590 ± 47 km s-1 measured from the rms variability spectrum, we obtain a virial estimate of M BH = 1.00+0.19-0.24 × 107 M⊙ for the black hole in Zw 229-015. As a Kepler target, Zw 229-015 will eventually have one of the highest-quality optical light curves ever measured for any active galaxy, and the black hole mass determined from reverberation mapping will serve as a benchmark for testing relationships between black hole mass and continuum variability characteristics in active galactic nuclei. © 2011. The American Astronomical Society. All rights reserved.

High-resolution in situ CO2 measurements were conducted aboard the NASA DC-8 aircraft during the ARCTAS/POLARCAT field campaign, a component of the wider 2007-2008 International Polar Year activities. Data were recorded during large-scale surveys spanning the North American sub-Arctic to the North Pole from 0.04 to 12 km altitude in spring and summer of 2008. Influences on the observed CO2 concentrations were investigated using coincident CO, black carbon, CH3CN, HCN, O3, C2Cl4, and Δ14CO2 data, and the FLEXPART model. In spring, the CO2 spatial distribution from 55̊N to 90̊N was largely determined by the long-range transport of air masses laden with Asian anthropogenic pollution intermingled with Eurasian fire emissions evidenced by the greater variability in the mid-to-upper troposphere. At the receptor site, the enhancement ratios of CO2 to CO in pollution plumes ranged from 27 to 80 ppmv ppmv-1 with the highest anthropogenic content registered in plumes sampled poleward of 80̊N. In summer, the CO2 signal largely reflected emissions from lightning-ignited wildfires within the boreal forests of northern Saskatchewan juxtaposed with uptake by the terrestrial biosphere. Measurements within fresh fire plumes yielded CO2 to CO emission ratios of 4 to 16 ppmv ppmv-1 and a mean CO2 emission factor of 1698 ± 280 g kg-1 dry matter. From the 14C in CO2 content of 48 whole air samples, mean spring (46.6 ± 4.4%) and summer (51.5 ± 5%) D14CO2 values indicate a 5%seasonal difference. Although the northern midlatitudes were identified as the emissions source regions for the majority of the spring samples, depleted Δ14CO2 values were observed in

It is now possible to estimate black hole (BH) masses across cosmic time, using broad emission lines in active galaxies. This technique informs our views of how galaxies and their central BHs coevolve. Unfortunately, there are many outstanding uncertainties associated with these "virial" mass estimates. One of these comes from using the accretion luminosity to infer a size for the broad-line region (BLR). Incorporating the new sample of low-luminosity active galaxies from our recent monitoring campaign at Lick Observatory, we recalibrate the radius-luminosity relation with tracers of the accretion luminosity other than the optical continuum. We find that the radius of the BLR scales as the square root of the X-ray and Hβ luminosities, in agreement with recent optical studies. On the other hand, the scaling appears to be marginally steeper with narrow-line luminosities. This is consistent with a previously observed decrease in the ratio of narrow-line to X-ray luminosity with increasing total luminosity. The radius of the BLR correlates most tightly with Hβ luminosity, while the X-ray and narrow-line relations both have comparable scatter of a factor of 2. These correlations provide useful alternative virial BH masses in objects with no detectable optical/UV continuum emission, such as high-redshift galaxies with broad emission lines, radio-loud objects, or local active galaxies with galaxy-dominated continua. © 2010. The American Astronomical Society.

We present velocity-delay maps for optical Hi, Hei, and He ii recombination lines in Arp 151, recovered by fitting a reverberation model to spectrophotometric monitoring data using the maximum-entropy method. Hi response is detected over the range 0-15 days, with the response confined within the virial envelope. The Balmer-line maps have similarmorphologies but exhibit radial stratification, with progressively longer delays for Hγ to Hβ to Hα. The He i and He ii response is confined within 1-2 days. There is a deficit of prompt response in the Balmer-line cores but strong prompt response in the red wings. Comparison with simple models identifies two classes that reproduce these features: free-falling gas and a half-illuminated disk with a hot spot at small radius on the receding lune. Symmetrically illuminated models with gas orbiting in an inclined disk or an isotropic distribution of randomly inclined circular orbits can reproduce the virial structure but not the observed asymmetry. Radial outflows are also largely ruled out by the observed asymmetry. A warped-disk geometry provides a physically plausible mechanism for the asymmetric illumination and hot spot features. Simple estimates show that a disk in the broad-line region of Arp 151 could be unstable to warping induced by radiation pressure. Our results demonstrate the potential power of detailed modeling combined with monitoring campaigns at higher cadence to characterize the gas kinematics and physical processes that give rise to the broad emission lines in active galactic nuclei. © 2010. The American Astronomical Society. All rights reserved.

Yong Seon Choi,1,* Hye-Min Sohn,2,* Sang-Hwan Do,2 Kyeong Tae Min,1 Jae Hee Woo,3 Hee Jung Baik3 1Department of Anesthesiology and Pain Medicine, Anesthesia and Pain Research Institute, Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea; 2Department of Anesthesiology and Pain Medicine, Seoul National University Bundang Hospital, Seongnam, Republic of Korea; 3Department of Anesthesiology and Pain Medicine, College of Medicine, Ewha Womans University, Seoul, Republic of Korea *These authors contributed equally to this work Background: Postoperative nausea and vomiting (PONV) is a common complication after surgery, which increases physical and psychological discomfort and delays recovery. The aim of this study was to test the hypothesis that ramosetron is comparable to ondansetron for the treatment of established PONV after laparoscopic surgery using a prospective, randomized, double-blinded, noninferiority study.Methods: Patients who had at least two risk factors of PONV and underwent laparoscopic surgery under general anesthesia were assessed for eligibility. Patients who developed PONV within the first 2 h after anesthesia received ondansetron (4 mg) or ramosetron (0.3 mg) intravenously in a randomized double-blind manner. Patients were then observed for 24 h after drug administration. The incidence of nausea and vomiting, severity of nausea, rescue antiemetic necessity, and adverse effects at 0–2 or 2–24 h after drug administration was evaluated. The primary endpoint was the rate of patients exhibiting a complete response, defined as no emesis and no further rescue antiemetic medication for 24 h after drug administration.Results: Among the 583 patients, 210 (36.0%) developed PONV and were randomized to either the ondansetron (n=105) or ramosetron (n=105) group. Patient’s characteristics were similar between the groups. The complete response rate was 44.1% in the ondansetron group and 52.9% in the ramosetron group after 24 h of initial antiemetic administration. The incidence of adverse events was not different between the groups.Conclusion: We found evidence to support the noninferiority of ramosetron (0.3 mg) compared to ondansetron (4 mg) for the treatment of established PONV in moderate to high-risk patients undergoing laparoscopic surgery. Keywords: laparoscopic surgery, ondansetron, postoperative nausea and vomiting, ramosetron, non-inferiority, antiemetic

To investigate the black hole mass versus stellar velocity dispersion (MBH-σ*) relation of active galaxies, we measured the velocity dispersions of a sample of local Seyfert 1 galaxies, for which we have recently determined black hole masses using reverberation mapping. For most objects, stellar velocity dispersions were measured from high signal-to-noise ratio optical spectra centered on the Ca II triplet region (∼ 8500 Å), obtained at the Keck, Palomar, and Lick Observatories. For two objects, in which the Ca II triplet region was contaminated by nuclear emission, the measurement was based on high-quality H-band spectra obtained with the OH-Suppressing Infrared Imaging Spectrograph at the Keck-II telescope. Combining our new measurements with data from the literature, we assemble a sample of 24 active galaxies with stellar velocity dispersions and reverberation-based black hole mass measurements in the range of black hole mass 106 < MBH/M⊙ < 109. We use this sample to obtain reverberation-mapping constraints on the slope and intrinsic scatter of the MBH-σ* relation of active galaxies. Assuming a constant virial coefficient f for the reverberation-mapping black hole masses, we find a slope β = 3.55 ± 0.60 and the intrinsic scatter σint = 0.43 ± 0.08 dex in the relation log(MBH/M⊙) = α + β log(σ*/200kms-1), which are consistent with those found for quiescent galaxies. We derive an updated value of the virial coefficient f by finding the value which places the reverberation masses in best agreement with the MBH-σ* relation of quiescent galaxies; using the quiescent MBH-σ* relation determined by Gültekin etal., we find log f = 0.72 +0.09-0.10 with an intrinsic scatter of 0.44 ± 0.07 dex. No strong correlations between f and parameters connected to the physics of accretion (such as the Eddington ratio or line-shape measurements) are found. The uncertainty of the virial coefficient remains one of the main sources of the uncertainty in black hole mass determinations using reverberation mapping, and therefore also in single-epoch spectroscopic estimates of black hole masses in active galaxies. © 2010 The American Astronomical Society.

We have recently completed a 64-night spectroscopic monitoring campaign at the Lick Observatory 3 m Shane telescope with the aim of measuring the masses of the black holes in 12 nearby (z < 0.05) Seyfert 1 galaxies with expected masses in the range ∼ 106-107 M ⊙ and also the well-studied nearby active galactic nucleus (AGN) NGC5548. Nine of the objects in the sample (including NGC5548) showed optical variability of sufficient strength during the monitoring campaign to allow for a time lag to be measured between the continuum fluctuations and the response to these fluctuations in the broad Hβ emission, which we have previously reported. We present here the light curves for the Hα, Hγ, He II λ4686, and He I λ5876 emission lines and the time lags for the emission-line responses relative to changes in the continuum flux. Combining each emission-line time lag with the measured width of the line in the variable part of the spectrum, we determine a virial mass of the central supermassive black hole from several independent emission lines. We find that the masses are generally consistent within the uncertainties. The time-lag response as a function of velocity across the Balmer line profiles is examined for six of the AGNs. We find similar responses across all three Balmer lines for Arp151, which shows a strongly asymmetric profile, and for SBS1116+583A and NGC6814, which show a symmetric response about zero velocity. For the other three AGNs, the data quality is somewhat lower and the velocity-resolved time-lag response is less clear. Finally, we compare several trends seen in the data set against the predictions from photoionization calculations as presented by Korista & Goad. We confirm several of their predictions, including an increase in responsivity and a decrease in the mean time lag as the excitation and ionization level for the species increases. Specifically, we find the time lags of the optical recombination lines to have weighted mean ratios of τ(Hα):τ(Hβ):τ(Hγ):τ(He I):τ(He II) = 1.54:1.00:0.61:0.36:0.25. Further confirmation of photoionization predictions for broad-line gas behavior will require additional monitoring programs for these AGNs while they are in different luminosity states. © 2010. The American Astronomical Society. All rights reserved.

The Lick AGN Monitoring Project targeted 13 nearby Seyfert 1 galaxies with the intent of measuring the masses of their central black holes using reverberation mapping. The sample includes 12 galaxies selected to have black holes with masses roughly in the range 106-107 M ⊙, as well as the well-studied active galactic nucleus (AGN) NGC 5548. In conjunction with a spectroscopic monitoring campaign, we obtained broadband B and V images on most nights from 2008 February through 2008 May. The imaging observations were carried out by four telescopes: the 0.76 m Katzman Automatic Imaging Telescope, the 2 m Multicolor Active Galactic Nuclei Monitoring telescope, the Palomar 60 inch (1.5 m) telescope, and the 0.80 m Tenagra II telescope. Having well-sampled light curves over the course of a few months is useful for obtaining the broad-line reverberation lag and black hole mass, and also allows us to examine the characteristics of the continuum variability. In this paper, we discuss the observational methods and the photometric measurements, and present the AGN continuum light curves. We measure various variability characteristics of each of the light curves. We do not detect any evidence for a time lag between the B- and V-band variations, and we do not find significant color variations for the AGNs in our sample. © 2009. The American Astronomical Society. All rights reserved.

A preliminary investigation was carried out by the US Environmental Protection Agency (EPA) on the impact of regional ozone concentrations on climate change in the country. The main objective of the investigation was to enhance the ability of air quality managers to consider global change in their decisions through improved characterization of the potential effects of global change on air quality, including O3, PM, and Hg. An integrated assessment framework was designed that supported the research and development efforts within the EPA and the academic research professionals. This design recognized the challenges of bridging spatial scales, temporal scales, and disciplines that characterize the global change and regional air quality problem. A major component of the assessment approach involved the development and application of global to regional climate and air quality modeling systems.

We have recently completed a 64-night spectroscopic monitoring campaign at the Lick Observatory 3-m Shane telescope with the aim of measuring the masses of the black holes in 12 nearby (z < 0.05) Seyfert 1 galaxies with expected masses in the range ∼ 106-107M and also the well-studied nearby active galactic nucleus (AGN) NGC 5548. Nine of the objects in the sample (including NGC 5548) showed optical variability of sufficient strength during the monitoring campaign to allow for a time lag to be measured between the continuum fluctuations and the response to these fluctuations in the broad Hβ emission. We present here the light curves for all the objects in this sample and the subsequent Hβ time lags for the nine objects where these measurements were possible. The Hβ lag time is directly related to the size of the broad-line region (BLR) in AGNs, and by combining the Hβ lag time with the measured width of the Hβ emission line in the variable part of the spectrum, we determine the virial mass of the central supermassive black hole in these nine AGNs. The absolute calibration of the black hole masses is based on the normalization derived by Onken et al., which brings the masses determined by reverberation mapping into agreement with the local MBH-σrelationship for quiescent galaxies. We also examine the time lag response as a function of velocity across the Hβ line profile for six of the AGNs. The analysis of four leads to rather ambiguous results with relatively flat time lags as a function of velocity. However, SBS 1116+583A exhibits a symmetric time lag response around the line center reminiscent of simple models for circularly orbiting BLR clouds, and Arp 151 shows an asymmetric profile that is most easily explained by a simple gravitational infall model. Further investigation will be necessary to fully understand the constraints placed on the physical models of the BLR by the velocity-resolved response in these objects.

A photometric sample of 8000 V < 25.3 candidate Lyman break galaxies (LBGs) has been selected by combining Subaru/Suprime-Cam BV R C i′z′ optical data with deep GALEX/NUV imaging of the Subaru Deep Field. Follow-up spectroscopy confirmed 24 LBGs at 1.5 ≲ z ≲ 2.7. Among the optical spectra, 12 have Lyα emission with rest-frame equivalent widths of 5-60 . The success rate for identifying LBGs as NUV-dropouts at 1.5 < z < 2.7 is 86%. The rest-frame UV (1700 ) luminosity function (LF) is constructed from the photometric sample with corrections for stellar contamination and z < 1.5 interlopers (lower limits). The LF is 1.7 0.1 (1.4 0.1 with a hard upper limit on stellar contamination) times higher than those of z 2 BXs and z 3 LBGs. Three explanations were considered, and it is argued that significantly underestimating low-z contamination or effective comoving volume is unlikely: the former would be inconsistent with the spectroscopic sample at 93% confidence, and the second explanation would not resolve the discrepancy. The third scenario is that different photometric selection of the samples yields nonidentical galaxy populations, such that some BX galaxies are LBGs and vice versa. This argument is supported by a higher surface density of LBGs at all magnitudes while the redshift distribution of the two populations is nearly identical. This study, when combined with other star formation rate (SFR) density UV measurements from LBG surveys, indicates that there is a rise in the SFR density: a factor of 3-6 (3-10) increase from z 5 (z 6) to z 2, followed by a decrease to z 0. This result, along with past sub-mm studies that find a peak at z 2 in their redshift distribution, suggests that z 2 is the epoch of peak star formation. © 2009. The American Astronomical Society.

Owing to its extremely high luminosity and long duration, supernova (SN) 2006gy radiated more energy in visual light than any other known SN. Two hypotheses to explain its high luminosity at early times - that it was powered by shock interaction with circumstellar material (CSM) as implied by its Type IIn spectrum, or that it was fueled by radioactive decay from a large mass of 56Ni synthesized in a pair-instability SN-predicted different late-time properties. Here we present observations of SN 2006gy obtained more than a year after discovery. We were unable to detect it at visual wavelengths, but clear near-infrared (IR) K′ and H-band detections show that it is still at least as luminous as the peak of a normal Type II SN. We also present spectra giving an upper limit to the late-time Ha luminosity of ≲S10 39 erg s-1. Based on the weak late-time Ha, X-ray, and radio emission, combined with the difficulty of explaining the shift to IR wavelengths, we can rule out ongoing CSM interaction as the primary late-time power source of SN 2006gy. Instead, we propose that the evolution of SN 2006gy is consistent with one of two possible scenarios: (1)apairinstability SN plus modest CSM interaction, where the radioactive decay luminosity shifts to the IR because of dust formation; or (2) an IR echo, where radiation emitted during peak luminosity heats a pre-existing dust shell at radii near 1 light year, requiring the progenitor star to have ejected another shell of ∼10 M ⊙ about 1500 yr before the SN. © 2008. The American Astronomical Society. All rights reserved.

We measure the evolution of the correlation between black hole mass and host spheroid velocity dispersion (MBH-σ*) over the last 6 billion years, by studying three carefully selected samples of active galaxies at z = 0.57, z = 0.36 and z < 0.1. For all three samples, virial black hole masses are consistently estimated using the line dispersion of Hβ and the continuum luminosity at 5100 Å or Hα line luminosity, based on our cross calibration of the broad-line region size-luminosity relation. For the z = 0.57 sample, new stellar velocity dispersions are measured from high signal-to-noise ratio spectra obtained at the Keck Telescope, while for the two lower redshift samples they are compiled from previous works. Extending our previous result at z = 0.36, we find an offset from the local relation, suggesting that for fixed MBH, distant spheroids have on average smaller velocity dispersions than local ones. The measured offset at z = 0.57 is Δ log σ* = 0.12 ± 0.05 ± 0.06 (or Δ log MBH = 0.50 ± 0.22 ± 0.25), i.e., Δ log M BH = (3.1 ± 1.5) log (1 + z) + 0.05 ± 0.21. This is inconsistent with a tight and nonevolving universal M BH-σ* relation at the 95% CL. © 2008. The American Astronomical Society. All rights reserved.

High resolution in situ measurements of atmospheric CO2 were made from the NASA DC-8 aircraft during the Intercontinental Chemical Transport Experiment - North America (INTEX-NA) campaign, part of the wider International Consortium for Atmospheric Research on Transport and Transformation (ICARTT). During the summer of 2004, eighteen flights comprising 160h of measurements were conducted within a region bounded by 27 to 53°N and 36 to 139°W over an altitude range of 0.15 to 12 km. These large-scale surveys provided the opportunity to examine the characteristics of the atmospheric CO2 signal over sparsely sampled areas of North America and adjacent ocean basins. The observations showed a high degree of variability (≤ 18%) due to the myriad source and sink processes influencing the air masses intercepted over the INTEX-NA sampling domain. Surface fluxes had strong effects on continental scale concentration gradients. Clear signatures of CO2 uptake were seen east of the Mississippi River, notably a persistent CO2 deficit in the lowest 2-3 km. When combining the airborne CO2 measurements with LANDSAT and MODIS data products, the lowest CO2 mixing ratios observed during the campaign (337 ppm) were tied to mid-continental agricultural fields planted in corn and soybeans. We used simultaneous measurements of CO, O3, C2Cl4, C2H6, C2H2 and other unique chemical tracers to differentiate air mass types. Coupling these distinct air mass chemical signatures with transport history permitted identification of convection, stratosphere-troposphere exchange, long-range transport from Eastern Asia, boreal wildfires, and continental outflow as competing processes at multiple scales influencing the observed concentrations. Our results suggest these are important factors contributing to the large-scale distribution in CO2 Mixing ratios thus these observations offer new constraints in the computation of the North American carbon budget. Copyright 2008 by the American Geophysical Union.

Black hole mass (MBH) is a fundamental property of active galactic nuclei (AGNs). In the distant universe, MBHis commonly estimated using the Mg II, Hβ, or Hα emission line widths and the optical/UV continuum or line luminosities as proxies for the characteristic velocity and size of the broad-line region. Although they all have a common calibration in the local universe, a number of different recipes are currently used in the literature. It is important to verify the relative accuracy and consistency of the recipes, as systematic changes could mimic evolutionary trends when comparing various samples. At z = 0.36, all three lines can be observed at optical wavelengths, providing a unique opportunity to compare different empirical recipes. We use spectra from the Keck Telescope and the Sloan Digital Sky Survey to compare MBHestimators for a sample of 19 AGNs at this redshift. We compare popular recipes available from the literature, finding that MBHestimates can differ up to 0.38 ± 0.05 dex in the mean (or 0.13 ± 0.05 dex, if the same virial coefficient is adopted). Finally, we provide a set of 30 internally self-consistent recipes for determining MBHfrom a variety of observables. The intrinsic scatter between cross-calibrated recipes is in the range 0.1-0.3 dex. This should be considered as a lower limit to the uncertainty of the MBHestimators. © 2008. The American Astronomical Society. All rights reserved.

We have recently completed a 64 night spectroscopic monitoring campaign at the Lick Observatory 3 m Shane telescope with the aim of measuring the masses of the black holes in 13 nearby (z

We use high-resolution images obtained with the Advanced Camera for Surveys on board the Hubble Space Telescope to determine morphology, nuclear luminosity, and structural parameters of the spheroidal component for a sample of 20 Seyfert galaxies atz = 0.36. We combine these measurements with spectroscopic information from the Keck Telescope to determine the black hole mass-spheroid luminosity relation (MBH-LB), the fundamental plane (FP) of the host galaxies, and the black hole mass-spheroid velocity dispersion relation (MBH-σ). The FP is consistent with that of inactive spheroids at comparable redshifts. Assuming pure luminosity evolution, we find that the host spheroids had smaller luminosity and stellar velocity dispersion than today for a fixed MBH. The offsets correspond to Δ log LB,0 = 0.40 ± 0.11 ± 0.15 (Δlog MBH= 0.51 ± 0.14 ± 0.19) and Δloge σ = 0.13 ± 0.03 ± 0.05 (Δlog MBH = 0.54 ± 0.12 ± 0.21), respectively, for the MBH-L and M BH-σ relations (the double error bars indicate random and ystematic uncertainties, respectively). A detailed analysis of known systematic errors and selection effects shows that they cannot account for the observed offset. We conclude that the data are inconsistent with pure luminosity evolution and the existence of universal and tight scaling relations. In order to obey the three local scaling relations by z = 0, assuming no significant black hole growth, the distant spheroids have to grow their stellar mass by approximately 60% (Δ log Msph = 0.20 ± 0.14) in the next 4 billion years, while preserving their size and holding their stellar mass-to-light ratio approximately constant. The measured evolution can be expressed as MBH/Msph ∝ (1 + z) 1.5±1.0, consistent with black holes of a few × 10 8 M⊙ completing their growth before their host galaxies. Based on the disturbed morphologies of a fraction of the sample (6/20), we suggest collisional mergers with disk-dominated systems as the physical mechanism driving the evolution. © 2007. The American Astronomical Society. All rights reserved.

We test the evolution of the correlation between black hole mass and bulge velocity dispersion (MBH-σ), using a carefully selected sample of 14 Seyfert 1 galaxies at z = 0.36±0.01. We measure velocity dispersion from stellar absorption lines around Mg b (5175 Å) and Fe (5270 Å) using high-S/N Keck spectra and estimate black hole mass from the Hβ line width and the optical luminosity at 5100 Å, based on the empirically calibrated photoionization method. We find a significant offset from the local relation, in the sense that velocity dispersions were smaller for given black hole masses at z = 0.36 than locally. We investigate various sources of systematic uncertainties and find that those cannot account for the observed offset. The measured offset is Δlog MBH = 0.62 ±0.10±0.25; i.e., Δlog σ = 0.15±0.03±0. 06, where the error bars include a random component and an upper limit to the systematics. At face value, this result implies a substantial growth of bulges in the last 4 Gyr, assuming that the local MBH-σ relation is the universal evolutionary endpoint. Along with two samples of active galaxies with consistently determined black hole mass and stellar velocity dispersion taken from the literature, we quantify the observed evolution with the best-fit linear relation: Δlog MBH = (1-66±0.43)z + (0.04±0.09) with respect to the local relationship of Tremaine and coworkers, and Δlog MBH = (1-55 ±0.46)z + (0.01 ±0.12) with respect to that of Ferrarese. This result is consistent with the growth of black holes predating the final growth of bulges at these mass scales (〈σ〉 = 170 km s-1). © 2006. The American Astronomical Society. All rights reserved.

We develop a source-specific high-resolution emission inventory for the Shandong region of eastern China for 2000 and 2020. Our emission estimates for year 2000 are higher than other studies for most pollutants, due to our inclusion of rural coal consumption, which is significant but often underestimated. Still, our inventory evaluation suggests that we likely underestimate actual emissions. We project that emissions will increase greatly from 2000 to 2020 if no additional emission controls are implemented. As a result, PM2.5 concentrations will increase; however O3 concentrations will decrease in most areas due to increased NOx emissions and VOC-limited O3 chemistry. Taking Zaozhuang Municipality in this region as a case study, we examine possible changes in emissions in 2020 given projected growth in energy consumption with no additional controls utilized (BAU), with adoption of best available end-of-pipe controls (BACT), and with advanced, low-emission coal gasification technologies (ACGT) which are capable of gasifying the high-sulfur coal that is abundant in China. Emissions of NH3 are projected to be 20% higher, NMVOC 50% higher, and all other species 130-250% higher in 2020 BAU than in 2000. Both alternative 2020 emission scenarios would reduce emissions relative to BAU. Adoption of ACGT, which meets only 24% of energy service demand in Zaozhuang in 2020 would reduce emissions more than BACT with 100% penetration. In addition, coal gasification technologies create an opportunity to reduce greenhouse gas emissions by capturing and sequestering CO2 emissions below ground. © 2005 Elsevier Ltd. All rights reserved.

The Pacific Exploration of Asian Continental Emission Phase A (PEACE-A) aircraft measurement campaign was conducted over the western Pacific in January 2002. Correlations of carbon monoxide (CO) with carbon dioxide (CO2) and back trajectories are used to identify plumes strongly affected by Asian continental emissions. ΔCO/ΔCO2 ratios (i.e., linear regression slopes of CO-CO2) in the plumes generally fall within the variability range of the CO/CO2 emission ratios estimated from an emission inventory for east Asia, demonstrating the consistency between the aircraft measurements and the emission characterization. Removal rates of reactive nitrogen (NOx and NOy) for the study region (altitude

An extensive set of carbonyl sulfide (OCS) and carbon disulfide (CS 2) observations were made as part of the NASA Transport and Chemical Evolution over the Pacific (TRACE-P) project, which took place in the early spring 2001. TRACE-P sampling focused on the western Pacific region but in total included the geographic region 110°E to 290°E longitude, 5°N to 50°N latitude, and 0-12 km altitude. Substantial OCS and CS2 enhancements were observed for a great many air masses of Chinese and Japanese origin during TRACE-P. Over the western Pacific, mean mixing ratios of long-lived OCS and shorter-lived CS2 showed a gradual decrease by about 10% and a factor of 5-10, respectively, from the surface to 8-10 km altitude, presumably because land-based sources dominated their distribution during February through April 2001. The highest mean OCS and CS 2 levels (580 and 20 pptv, respectively, based on 2.5° × 2.5° latitude bins) were observed below 2 km near the coast of Asia, at latitudes between 25°N and 35°N, where urban Asian outflow was strongest. Ratios of OCS versus CO for continental SE Asia were much lower compared to Chinese and Japanese signatures and were strongly associated with biomass burning/biofuel emissions. We present a new inventory of anthropogenic Asian emissions (including biomass burning) for OCS and CS2 and compare it to emission estimates based on regional relationships of OCS and CS 2 to CO and CO2. The OCS and CS2 results for the two methods compare well for continental SE Asia and Japan plus Korea and also for Chinese CS2 emissions. However, it appears that the inventory underestimates Chinese emissions of OCS by about 30-100%. This difference may be related to the fact that we did not include natural sources such as wetland emissions in our inventory, although the contributions from such sources are believed to be at a seasonal low during the study period. Uncertainties in OCS emissions from Chinese coal burning, which are poorly characterized, likely contribute to the discrepancy. Copyright 2004 by the American Geophysical Union.