197 research outputs found

    Black Hole Mass Estimates Based on CIV are Consistent with Those Based on the Balmer Lines

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    Using a sample of high-redshift lensed quasars from the CASTLES project with observed-frame ultraviolet or optical and near-infrared spectra, we have searched for possible biases between supermassive black hole (BH) mass estimates based on the CIV, Halpha and Hbeta broad emission lines. Our sample is based upon that of Greene, Peng & Ludwig, expanded with new near-IR spectroscopic observations, consistently analyzed high S/N optical spectra, and consistent continuum luminosity estimates at 5100A. We find that BH mass estimates based on the FWHM of CIV show a systematic offset with respect to those obtained from the line dispersion, sigma_l, of the same emission line, but not with those obtained from the FWHM of Halpha and Hbeta. The magnitude of the offset depends on the treatment of the HeII and FeII emission blended with CIV, but there is little scatter for any fixed measurement prescription. While we otherwise find no systematic offsets between CIV and Balmer line mass estimates, we do find that the residuals between them are strongly correlated with the ratio of the UV and optical continuum luminosities. Removing this dependency reduces the scatter between the UV- and optical-based BH mass estimates by a factor of approximately 2, from roughly 0.35 to 0.18 dex. The dispersion is smallest when comparing the CIV sigma_l mass estimate, after removing the offset from the FWHM estimates, and either Balmer line mass estimate. The correlation with the continuum slope is likely due to a combination of reddening, host contamination and object-dependent SED shapes. When we add additional heterogeneous measurements from the literature, the results are unchanged.Comment: Accepted for publication in The Astrophysical Journal. 37 text pages + 8 tables + 23 figures. Updated with comments by the referee and with a expanded discussion on literature data including new observation

    Evaluation of intranasal dexmedetomidine in providing moderate sedation in patients undergoing ERCP: A randomized controlled trial

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    Background and purpose: Endoscopic retrograde cholangiopancreatography (ERCP) is usually performed under deep sedation. Respiratory depression and airway obstruction are the most dangerous complications of sedatives. Dexmedetomidine is a drug that does not cause respiratory depression so, this study evaluated the efficacy of nasal dexmedetomidine in inducing moderate sedation in patients undergoing ERCP. Materials and methods: In a double blind randomized controlled trial, the patients candidate for ERCP in Firoozgar hospital, were divided into two groups. Group I received normal saline while in group II dexmedetomidine 1μg/kg was administered intranasaly. Also, intravenous midazolam and fentanyl, and if needed, propofol were used for induction of sedation. Then total use of sedative drugs, hemodynamic parameters, patient and physician satisfaction and side effects of treatment were documented. Results: There were no significant differences in age, sex and BMI between the two groups. Mean use of midazolam and fentanyl was almost similar in two groups but the use of propofol was lower in group II (P= 0.002). The mean heart rate was found to be lower in the group receiving dexmedetomidine but systolic and diastolic blood pressure were almost similar in two groups (P> 0.05). Compared with the results in group I, the patients and physicians in group II were more satisfied with dexmedetomidine. Conclusion: Dexmedetomidine as an adjuvant drug for sedation in patients undergoing ERCP could reduce the need for other sedatives, and also satisfy both the patients and therapists. © 2016, Mazandaran University of Medical Sciences. All Rights reserved

    Dual-Frequency SIW Slot Array Antenna for Automotive Radar: configurable FoV, Performance Evaluation, and Tolerance Analysis

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    This paper presents a single-layer SIW longitudinal slot array antenna optimized for high gain and low side lobe levels (SLL) in the W-band, designed for LMRR (Long Medium Range Radar) applications. This design enhances detection range at high frequencies. It also provides a wider azimuth field of view (FOV) at lower frequencies. The approach improves compactness and reduces costs. It eliminates the need for multiple antennas in different radar ranges. The system includes two band pass filters (BPFs) and one power divider. These components integrate into four antenna arrays, each with six slots. The results show a 4.6 dB gain improvement between lower and higher frequency bands. The antenna extends the maximum detection range by 168 m for a vehicle with an RCS of 10 dBsm in a lossless system. Additionally, the study analyses the normalized admittance of the antenna. It examines the effects of slot length, width, and displacement on conductance and susceptance. These findings confirm the antenna's efficiency for radar applications. A comprehensive tolerance analysis was performed to assess the proposed design's robustness under variations in key parameters.</p

    Elevated gamma-glutamyl transferase is associated with subclinical inflammation independent of cardiometabolic risk factors in an asymptomatic population: a cross-sectional study

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    BACKGROUND: Serum Gamma-Glutamyl Transferase (GGT), a marker of oxidative stress, has been suggested to be independently associated with cardiovascular disease (CVD) events. We examined the association of serum GGT levels with the burden of subclinical inflammation across a spectrum of metabolic conditions. METHODS: We evaluated 5,446 asymptomatic subjects (43 ± 10 years, 78 % males) who had an employer-sponsored physical between 2008 and 2010. Highly sensitivity C-reactive protein (hsCRP) was measured as a marker of underlying systemic inflammation. A linear regression of GGT quartiles with log transformed hsCRP and a multivariate logistic regression of GGT quartiles with elevated hsCRP (≥3 mg/L) were performed. RESULTS: Median GGT was 31 IU/l (IQR: 22–45 IU/l), 1025 (19 %) had hsCRP ≥ 3 mg/L. The median hsCRP increased with GGT quartiles (Q1: 0.9 mg/L, Q2: 1.1 mg/L, Q3: 1.4 mg/L, Q4: 1.6 mg/L, p < 0.001). Linear regression models showed GGT in the fourth quartile was associated with 0.45 mg/L (95 % CI 0.35, 0.54, p < 0.001) increase in log transformed hsCRP adjusting for risk factors. The Odds Ratio (OR) for an elevated hsCRP (≥3 mg/L) also increased with higher GGT quartiles; GGT Q2 1.44 (95 % CI 1.12, 1.85), GGT Q3 1.89 (95 % CI 1.45, 2.46), GGT Q4 2.22 (95 % CI 1.67, 2.95), compared to GGT Q1. The strength of association increased in the presence of and combination of metabolic conditions. CONCLUSION: In our cohort of asymptomatic individuals a higher serum GGT level was independently associated with increased burden of subclinical inflammation across metabolic states. These findings may explain GGT association with increased CVD risk

    Infrared Narrow-Band Tomography of the Local Starburst NGC 1569 with LBT/LUCIFER

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    We used the near-IR imager/spectrograph LUCIFER mounted on the Large Binocular Telescope (LBT) to image, with sub-arcsec seeing, the local dwarf starburst NGC 1569 in the JHK bands and HeI 1.08 micron, [FeII] 1.64 micron and Brgamma narrow-band filters. We obtained high-quality spatial maps of HeI, [FeII] and Brgamma emission across the galaxy, and used them together with HST/ACS images of NGC 1569 in the Halpha filter to derive the two-dimensional spatial map of the dust extinction and surface star formation rate density. We show that dust extinction is rather patchy and, on average, higher in the North-West (NW) portion of the galaxy [E_g(B-V) = 0.71 mag] than in the South-East [E_g(B-V) = 0.57 mag]. Similarly, the surface density of star formation rate peaks in the NW region of NGC 1569, reaching a value of about 4 x 10^-6 M_sun yr^-1 pc^-2. The total star formation rate as estimated from the integrated, dereddened Halpha luminosity is about 0.4 M_sun yr^-1, and the total supernova rate from the integrated, dereddened [FeII] luminosity is about 0.005 yr^-1 (assuming a distance of 3.36 Mpc). The azimuthally averaged [FeII]/Brgamma flux ratio is larger at the edges of the central, gas-deficient cavities (encompassing the super star clusters A and B) and in the galaxy outskirts. If we interpret this line ratio as the ratio between the average past star formation (as traced by supernovae) and on-going activity (represented by OB stars able to ionize the interstellar medium), it would then indicate that star formation has been quenched within the central cavities and lately triggered in a ring around them. The number of ionizing hydrogen and helium photons as computed from the integrated, dereddened Halpha and HeI luminosities suggests that the latest burst of star formation occurred about 4 Myr ago and produced new stars with a total mass of ~1.8 x 10^6 M_sun. [Abridged]Comment: accepted for publication in A

    TILLING - a shortcut in functional genomics

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    Recent advances in large-scale genome sequencing projects have opened up new possibilities for the application of conventional mutation techniques in not only forward but also reverse genetics strategies. TILLING (Targeting Induced Local Lesions IN Genomes) was developed a decade ago as an alternative to insertional mutagenesis. It takes advantage of classical mutagenesis, sequence availability and high-throughput screening for nucleotide polymorphisms in a targeted sequence. The main advantage of TILLING as a reverse genetics strategy is that it can be applied to any species, regardless of its genome size and ploidy level. The TILLING protocol provides a high frequency of point mutations distributed randomly in the genome. The great mutagenic potential of chemical agents to generate a high rate of nucleotide substitutions has been proven by the high density of mutations reported for TILLING populations in various plant species. For most of them, the analysis of several genes revealed 1 mutation/200–500 kb screened and much higher densities were observed for polyploid species, such as wheat. High-throughput TILLING permits the rapid and low-cost discovery of new alleles that are induced in plants. Several research centres have established a TILLING public service for various plant species. The recent trends in TILLING procedures rely on the diversification of bioinformatic tools, new methods of mutation detection, including mismatch-specific and sensitive endonucleases, but also various alternatives for LI-COR screening and single nucleotide polymorphism (SNP) discovery using next-generation sequencing technologies. The TILLING strategy has found numerous applications in functional genomics. Additionally, wide applications of this throughput method in basic and applied research have already been implemented through modifications of the original TILLING strategy, such as Ecotilling or Deletion TILLING

    Antimicrobial de-escalation in the critically ill patient and assessment of clinical cure: the DIANA study

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    Purpose: The DIANA study aimed to evaluate how often antimicrobial de-escalation (ADE) of empirical treatment is performed in the intensive care unit (ICU) and to estimate the effect of ADE on clinical cure on day 7 following treatment initiation. Methods: Adult ICU patients receiving empirical antimicrobial therapy for bacterial infection were studied in a prospective observational study from October 2016 until May 2018. ADE was defined as (1) discontinuation of an antimicrobial in case of empirical combination therapy or (2) replacement of an antimicrobial with the intention to narrow the antimicrobial spectrum, within the first 3&nbsp;days of therapy. Inverse probability (IP) weighting was used to account for time-varying confounding when estimating the effect of ADE on clinical cure. Results: Overall, 1495 patients from 152 ICUs in 28 countries were studied. Combination therapy was prescribed in 50%, and carbapenems were prescribed in 26% of patients. Empirical therapy underwent ADE, no change and change other than ADE within the first 3&nbsp;days in 16%, 63% and 22%, respectively. Unadjusted mortality at day 28 was 15.8% in the ADE cohort and 19.4% in patients with no change [p = 0.27; RR 0.83 (95% CI 0.60\u20131.14)]. The IP-weighted relative risk estimate for clinical cure comparing ADE with no-ADE patients (no change or change other than ADE) was 1.37 (95% CI 1.14\u20131.64). Conclusion: ADE was infrequently applied in critically ill-infected patients. The observational effect estimate on clinical cure suggested no deleterious impact of ADE compared to no-ADE. However, residual confounding is likely
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