Extended Structures of Planetary Nebulae Detected in H2 Emission

Original content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.We present narrowband near-infrared images of a sample of 11 Galactic planetary nebulae (PNe) obtained in the H 2.122 μm and Brγ 2.166 μm emission lines and the K 2.218 μm continuum. These images were collected with the Wide-field Infrared Camera on the 3.6 m Canada-France-Hawaii Telescope (CFHT); their unprecedented depth and wide field of view allow us to find extended nebular structures in H emission in several PNe, some of these being the first detection. The nebular morphologies in H emission are studied in analogy with the optical images, and indication of stellar wind interactions is discussed. In particular, the complete structure of the highly asymmetric halo in NGC 6772 is witnessed in H, which strongly suggests interaction with the interstellar medium. Our sample confirms the general correlation between H emission and the bipolarity of PNe. The knotty or filamentary fine structures of the H gas are resolved in the inner regions of several ring-like PNe, also confirming the previous argument that H emission mostly comes from knots or clumps embedded within fully ionized material at the equatorial regions. Moreover, the H image of the butterfly-shaped Sh 1-89, after removal of field stars, clearly reveals a tilted ring structure at the waist. These high-quality CFHT images justify follow-up detailed morphokinematic studies that are desired in order to deduce the true physical structures of a few PNe in the sample.© 2018. The American Astronomical Society.© 2018. The American Astronomical Society.Part of the data presented here were obtained with ALFOSC, which is provided by the Instituto de Astrofisica de Andalucia (IAA-CSIC) under a joint agreement with the University of Copenhagen and NOSTA, and the 1.5 m telescope at San Pedro Martir of the National Astronomical Observatory (OAN) operated by Universidad Nacional Autonoma de Mexico (UNAM). Financial support for this work was provided by the Research Grants Council of Hong Kong under grant HKU 7027/11P C.-H.H. acknowledges financial support from the Science and Technology Development Fund of Macau (project No. 119/2017/A3 and 061/2017/A2). M.A.G. acknowledges support of the grant AYA 2014-57280-P, cofunded with FEDER funds. This research uses data obtained through the Telescope Access Program (TAP), which has been funded by the National Astronomical Observatories of China, the Chinese Academy of Sciences (the Strategic Priority Research Program >The Emergence of Cosmological Structures> Grant No. XDB09000000), and the Special Fund for Astronomy from the Ministry of Finance. This research made use of the SIMBAD database, operated at CDS, Strasbourg, France, and of NASA's Astrophysics Data System Bibliographic Services. We thank Quentin A. Parker and Foteini Lykou for their reading of the manuscript and comments. This research has made use of the HST archival data from MAST, the Mikulski Archive for Space Telescope at the Space Telescope Science Institute (STScI), which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS5-26555. Support for MAST for non-HST data is provided by the NASA Office of Space Science via grant NAG5-7584 and by other grants and contracts. This publication makes use of data products from the Wide-field Infrared Survey Explorer (WISE), which is a joint project of the University of California, Los Angeles, and the Jet Propulsion Laboratory/California Institute of Technology, funded by the National Aeronautics and Space Administration. This research also utilized the software SAOImage. DS9 (Joye & Mandel 2003) developed by the Smithsonian Astrophysical Observatory

Mortality risk factors in patients with Acinetobacter baumannii ventilator-associated pneumonia

Background/PurposeVentilator-associated pneumonia (VAP) caused by Acinetobacter baumannii has contributed to high mortality rate, prolonged stays in the intensive care unit, and the rapid development of antimicrobial resistance to commonly used antimicrobials. This study sought to determine predictors of mortality and carbapenem resistance for patients with A baumannii VAP.MethodsWe retrospectively reviewed 541 adult patients with A baumannii pneumonia, who were admitted to a medical center between 2005 and 2007; of which 180 (33.3%) had been treated with mechanical ventilation. Of the 180 patients, 98 (54.4%) who survived were categorized as the survivor group, and 82 (45.6%) who died as the mortality group. Eighty-seven (48.3%) with imipenem-sensitive A baumannii VAP were categorized as the IS-AB group, and the remaining 93 (51.7%) with imipenem-resistant VAP as the IR-AB group.ResultsCompared with the survivor group, the mortality group had significantly higher Charlson comorbidity index scores, and more neoplastic disease, other sites of infection, bloodstream infections, altered mental status, confusion, urea >7 mmol/L, respiratory rate >30/min, low blood pressure (systolic <90 mmHg or diastolic <60 mmHg), age >65 years (CURB-65) ≥ 3, creatinine > 1.6 mg/dL, C-reactive protein ≥ 100 mg/L, and imipenem resistance. The survivor group had more cases of tracheostomy and diabetes mellitus than the mortality group had. Compared with the IS-AB group, the IR-AB group had higher Charlson comorbidity index scores, longer stays before VAP onset, an increase in other sites of infection, white blood cell count <4/μL or >1.1 × 104/μL, and higher hospital mortality rates.ConclusionInadequate initial empiric antimicrobial therapy and higher disease severity scores, including CURB ≥ 3 and C-reactive protein ≥ 120 mg/L, were independent risk factors associated with higher mortality rates for A baumannii pneumonia. Length of stay before VAP and white blood cell count <4/μL or >1.1 × 104/μL were independent risk factors for carbapenem resistance

Identifying and Analyzing Sepsis States: A Retrospective Study on Patients with Sepsis in ICUs

Sepsis accounts for more than 50% of hospital deaths, and the associated cost ranks the highest among hospital admissions in the US. Improved understanding of disease states, severity, and clinical markers has the potential to significantly improve patient outcomes and reduce cost. We develop a computational framework that identifies disease states in sepsis using clinical variables and samples in the MIMIC-III database. We identify six distinct patient states in sepsis, each associated with different manifestations of organ dysfunction. We find that patients in different sepsis states are statistically significantly composed of distinct populations with disparate demographic and comorbidity profiles. Collectively, our framework provides a holistic view of sepsis, and our findings provide the basis for future development of clinical trials and therapeutic strategies for sepsis