Possible X-ray diagnostic for jet/disk dominance in Type 1 AGN

Using Rossi X-ray Timing Explorer Seyfert 1 and 1.2 data spanning 9 years, we study correlations between X-ray spectral features. The sample consists of 350 time-resolved spectra from 12 Seyfert 1 and 1.2 galaxies. Each spectrum is fitted to a model with an intrinsic powerlaw X-ray spectrum produced close to the central black hole that is reprocessed and absorbed by material around the black hole. To test the robustness of our results, we performed Monte Carlo simulations of the spectral sample. We find a complex relationship between the iron line equivalent width (EW) and the underlying power law index (Gamma). The data reveal a correlation between Gamma and EW which turns over at Gamma <~ 2, but finds a weak anti-correlation for steeper photon indices. We propose that this relationship is driven by dilution of a disk spectrum (which includes the narrow iron line) by a beamed jet component and, hence, could be used as a diagnostic of jet-dominance. In addition, our sample shows a strong correlation between the reflection fraction (R) and Gamma, but we find that it is likely the result of modeling degeneracies. We also see the X-ray Baldwin effect (an anti-correlation between the 2-10 keV X-ray luminosity and EW) for the sample as a whole, but not for the individual galaxies and galaxy types.Comment: Accepted for publication in ApJ, 14 page

Book Reviews

Reviews of the following books: Little Pine to King Spruce: A Franco-American Childhood by Fran Pelletier; This Splendid Game: Maine Campaigns and Elections, 1940-2002 by Christian P. Potholm; Giving Voters a Voice: The Origins of the Initiative and Referendum in America by Steven L. Piott; The Interrupted Forest: A History of Maine\u27s Wildlands by Neil Rold

Effect of an Enrichment Program on DAT Scores of Potential Dental Students from Disadvantaged Backgrounds

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/153585/1/jddj002203372013778tb05575x.pd

Risk for Clostridium difficile infection after allogeneic hematopoietic cell transplant remains elevated in the postengraftment period

BACKGROUND: Clostridium difficile infection (CDI) is a frequent cause of diarrhea among allogeneic hematopoietic cell transplant (HCT) recipients. It is unknown whether risk factors for CDI vary by time posttransplant. METHODS: We performed a 3-year prospective cohort study of CDI in allogeneic HCT recipients. Participants were enrolled during their transplant hospitalizations. Clinical assessments were performed weekly during hospitalizations and for 12 weeks posttransplant, and monthly for 30 months thereafter. Data were collected through patient interviews and chart review, and included CDI diagnosis, demographics, transplant characteristics, medications, infections, and outcomes. CDI cases were included if they occurred within 1 year of HCT and were stratified by time from transplant. Multivariable logistic regression was used to determine risk factors for CDI. RESULTS: One hundred eighty-seven allogeneic HCT recipients were enrolled, including 63 (34%) patients who developed CDI. 38 (60%) CDI cases occurred during the preengraftment period (days 0-30 post-HCT) and 25 (40%) postengraftment (day >30). Lack of any preexisting comorbid disease was significantly associated with lower risk of CDI preengraftment (odds ratio [OR], 0.3; 95% confidence interval [CI], 0.1-0.9). Relapsed underlying disease (OR, 6.7; 95% CI, 1.3-33.1), receipt of any high-risk antimicrobials (OR, 11.8; 95% CI, 2.9-47.8), and graft-versus-host disease (OR, 7.8; 95% CI, 2.0-30.2) were significant independent risk factors for CDI postengraftment. CONCLUSIONS: A large portion of CDI cases occurred during the postengraftment period in allogeneic HCT recipients, suggesting that surveillance for CDI should continue beyond the transplant hospitalization and preengraftment period. Patients with continued high underlying severity of illness were at increased risk of CDI postengraftment

Temporal changes in Weddell seal dive behavior over winter: are females increasing foraging effort to support gestation?

© The Author(s), 2018. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Ecology and Evolution, 8(23), (2018): 11857-11874. doi: 10.1002/ece3.4643.In capital‐breeding marine mammals, prey acquisition during the foraging trip coinciding with gestation must provide energy to meet the immediate needs of the growing fetus and also a store to meet the subsequent demands of lactation. Weddell seals (Leptonychotes weddellii) that give birth following the gestational (winter) foraging period gain similar proportions of mass and lipid as compared to females that fail to give birth. Therefore, any changes in foraging behavior can be attributed to gestational costs. To investigate differences in foraging effort associated with successful reproduction, twenty‐three satellite tags were deployed on post‐molt female Weddell seals in the Ross Sea. Of the 20 females that returned to the area the following year, 12 females gave birth and eight did not. Females that gave birth the following year began the winter foraging period with significantly longer and deeper dives, as compared to non‐reproductive seals. Mid‐ to late winter, reproductive females spent a significantly greater proportion of the day diving, and either depressed their diving metabolic rates (DMR), or exceeded their calculated aerobic dive limit (cADL) more frequently than females that returned without a pup. Moreover, non‐reproductive females organized their dives into 2–3 short bouts per day on average (BOUTshort; 7.06 ± 1.29 hr; mean ± 95% CI), whereas reproductive females made 1–2 BOUTshort per day (10.9 ± 2.84 hr), comprising one long daily foraging bout without rest. The magnitude of the increase in dive activity budgets and depression in calculated DMR closely matched the estimated energetic requirements of supporting a fetus. This study is one of the first to identify increases in foraging effort that are associated with successful reproduction in a top predator and indicates that reproductive females must operate closer to their physiological limits to support gestational costs.We are grateful for the help of field team members: Drs. Luis Hückstädt, Linnea Pearson, and Patrick Robinson for sample collection. Group B‐009‐M led by Drs. Robert Garrott, Jay Rotella, and Thierry Chambert provided information regarding animal reproductive status and provided great assistance in locating study animals. Logistical support was provided by the National Science Foundation (NSF) U.S. Antarctic Program, Raytheon Polar Services, and Lockheed Martin ASC; we thank all the support staff in Christchurch, NZ and McMurdo Station. This research was conducted with support from NSF ANT‐0838892 to D.P.C. and ANT‐0838937 to J.M.B. For J.M.B., this material is based upon work while serving at the National Science Foundation, and M.R.S was supported by the National Science Foundation Graduate Research Fellowship under Grant No. DGE‐1242789. Any opinion, findings and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the National Science Foundation. Animal handling protocols were approved by the University of Alaska Anchorage and University of California Santa Cruz's Institutional Animal Care and Use Committees. Research and sample import to the United States were authorized under the Marine Mammal permit No. 87‐1851‐04 issued by the Office of Protected Resources, National Marine Fisheries Service. Research activities were also approved through Antarctic Conservation Act permits while at McMurdo Station

Fe XXV and Fe XXVI Diagnostics of the Black Hole and Accretion Disk in Active Galaxies: Chandra Time-Resolved Spectroscopy of NGC 7314

We report the detection of Fe XXV and Fe XXVI $K\alpha$ emission lines from a Chandra HETGS observation of the Seyfert~1 galaxy NGC 7314, made simultaneously with RXTE. The lines are redshifted (cz ~ 1500 km/s) relative to the systemic velocity and unresolved. We argue that the lines originate in a near face-on (<7 degrees) disk having a radial line emissivity flatter than r^-2. Line emission from ionization states of Fe in the range ~Fe I up to Fe XXVI is observed. The ionization balance of Fe responds to continuum variations on timescales less than 12.5 ks, supporting an origin of the lines close to the X-ray source. We present additional, detailed diagnostics from this rich data set. These results identify NGC 7314 as a key source to study in the future if we are to pursue reverberation mapping of space-time near black-hole event horizons. This is because it is first necessary to understand the ionization structure of accretion disks and the relation between the X-ray continuum and Fe K line emission. However, we also describe how our results are suggestive of a means of measuring black-hole spin without a knowledge of the relation between the continuum and line emission. Finally, these data emphasize that one {\it can} study strong gravity with narrow (as opposed to very broad) disk lines. In fact narrow lines offer higher precision, given sufficient energy resolution.Comment: Accepted for publication in the Astrophysical Journal. 30 pages, six figures, five of them color. Abstract is abridge

EBV-Associated Smooth Muscle Neoplasms: Solid Tumors Arising in the Presence of Immunosuppression and Autoimmune Diseases

Background. Epstein-Barr virus (EBV)-related smooth muscle neoplasms (SMNs) have been associated with immune dysregulation, most notably in patients who have undergone solid organ transplantation or in patients with HIV/AIDS. Objective. to report our experience with EBV-related neoplasms as well as describing the first EBV-related SMN in the setting of administration of glucocorticoids and the tumor necrosis factor inhibitor etanercept. Design. We have case reports, of minimum 3-year follow-up, 2002–2005. Setting. It was held in an academic and tertiary referral cancer center. Patients. Patients are with dysregulated immunity after solid organ transplantation, HIV/AIDS, or with psoriasis after treatment with etanercept. Interventions. There were discontinuation of etanercept, right hepatic trisegmentectomy, and chemotherapy. Measurements. We use survival as a measurement here. Results. Patients who were able to withstand reduction in immunosuppression survived. Surgical resection or chemotherapy was successful in delaying progression of disease. Limitations. There was a relatively short follow-up for these slow-growing neoplasms. Conclusion. EBV-related SMNs have variable aggressiveness. While chemotherapy may slow disease progression, resection and improving the host immune status provide the best opportunity for primary tumor control

Non-Linear Relativity in Position Space

We propose two methods for obtaining the dual of non-linear relativity as previously formulated in momentum space. In the first we allow for the (dual) position space to acquire a non-linear representation of the Lorentz group independently of the chosen representation in momentum space. This requires a non-linear definition for the invariant contraction between momentum and position spaces. The second approach, instead, respects the linearity of the invariant contraction. This fully fixes the dual of momentum space and dictates a set of energy-dependent space-time Lorentz transformations. We discuss a variety of physical implications that would distinguish these two strategies. We also show how they point to two rather distinct formulations of theories of gravity with an invariant energy and/or length scale.Comment: 7 pages, revised versio