14,397 research outputs found
Integral Inequalities and their Applications to the Calculus of Variations on Time Scales
We discuss the use of inequalities to obtain the solution of certain
variational problems on time scales.Comment: To appear in Mathematical Inequalities & Applications
(http://mia.ele-math.com). Accepted: 14.01.201
How does breakup influence the total fusion of Li at the Coulomb barrier?
Total (complete + incomplete) fusion excitation functions of Li on
Co and Bi targets around the Coulomb barrier are obtained using
a new continuum discretized coupled channel (CDCC) method of calculating
fusion. The relative importance of breakup and bound-state structure effects on
total fusion is particularly investigated. The effect of breakup on fusion can
be observed in the total fusion excitation function. The breakup enhances the
total fusion at energies just around the barrier, whereas it hardly affects the
total fusion at energies well above the barrier. The difference between the
experimental total fusion cross sections for Li on Co is notably
caused by breakup, but this is not the case for the Bi target.Comment: 9 pages, 9 figures, Submitted to Phys. Rev.
VLT and GTC observations of SDSS J0123+00: a type 2 quasar triggered in a galaxy encounter?
We present long-slit spectroscopy, continuum and [OIII]5007 imaging data
obtained with the Very Large Telescope and the Gran Telescopio Canarias of the
type 2 quasar SDSS J0123+00 at z=0.399. The quasar lies in a complex, gas-rich
environment. It appears to be physically connected by a tidal bridge to another
galaxy at a projected distance of ~100 kpc, which suggests this is an
interacting system. Ionized gas is detected to a distance of at least ~133 kpc
from the nucleus. The nebula has a total extension of ~180 kpc. This is one of
the largest ionized nebulae ever detected associated with an active galaxy.
Based on the environmental properties, we propose that the origin of the nebula
is tidal debris from a galactic encounter, which could as well be the
triggering mechanism of the nuclear activity. SDSS J0123+00 demonstrates that
giant, luminous ionized nebulae can exist associated with type 2 quasars of low
radio luminosities, contrary to expectations based on type 1 quasar studies.Comment: 6 pages, 5 figures. Accepted for publication in MNRAS Letter
Fully Interactive and Refined Resolution Simulations of the Martian Dust Cycle by the MarsWRF Model
Acknowledgments: First of all, our warmest thanks go to the PlanetWRF development team for providing the MarsWRF model free of charge to us and their proactive attitude in general. We thank Andy Heaps, National Centre for Atmospheric Science (NCAS), Department of Meteorology, University of Reading, UK, for his helpful advice regarding the data visualization using cf‐Python. We would also like to thank Michael Mischna, Alexandre Kling, and the Associate Editor Claire Newman for their several detailed and insightful comments and suggestions that helped to significantly improve the quality of the paper. M. P. Z. acknowledges the partial support by the Spanish State Research Agency (AEI) project MDM‐2017‐0737 Centro de Astrobiología (CSIC‐INTA), Unidad de Excelencia María de Maeztu. Internally, we would like to express our greatest thanks to the High‐Performance Computing, Division of Information Technology, United Arab Emirates University. Our particular thanks go to Asma AlNeyadi, Anil Thomas, and Nithin Damodaran for their intensive and continuous support in technically demanding questions. Also, we would like to thank the Digitization Unit, UAEU Libraries, for the digitization of auxiliary data on the observational record of the atmospheric T15 temperature and vertical weighting functions of Viking/IRTM. In addition, we thank UAEU Libraries for their assistance in making supporting data of this article available online. In particular, we are grateful to Digitization Technician Shireen M. Wolied, Fadl M. Musa/Digital Library Service, and Student Muhammad Abdul Rahim Sami Ullah. Funding Information: United Arab Emirates University (UAEU). Grant Number: 21R033‐NSS Center 7‐2017 Spanish State Research Agency (AEI). Grant Number: MDM‐2017‐0737Peer reviewedPublisher PD
Necrobiosis lipoidica developing within a surgical scar in a non-diabetic patient: Type III Koebner phenomenon (isomorphic response), Wolf's isotopic response or Ruocco's immunocompromised cutaneous district?
Sir, Necrobiosis lipoidica is a chronic granulomatous disease typically associated with diabetes mellitus. We report a case of necrobiosis lipoidica occurring in a surgical scar in a non-diabetic patient. We found only nine previous reports of necrobiosis lipoidica appearing after trauma or in surgical scars, as a manifestation of Type III Koebner phenomenon. Most of these were in diabetic patients..
Crossover from Electronic to Atomic Shell Structure in Alkali Metal Nanowires
After making a cold weld by pressing two clean metal surfaces together, upon
gradually separating the two pieces a metallic nanowire is formed, which
progressively thins down to a single atom before contact is lost. In previous
experiments [1,2] we have observed that the stability of such nanowires is
influenced by electronic shell filling effects, in analogy to shell effects in
metal clusters [3]. For sodium and potassium at larger diameters there is a
crossover to crystalline wires with shell-closings corresponding to the
completion of additional atomic layers. This observation completes the analogy
between shell effects observed for clusters and nanowires.Comment: 4 page
Galaxy-wide radio-induced feedback in a radio-quiet quasar
We report the discovery of a radio-quiet type 2 quasar (SDSS J165315.06+234943.0 nicknamed the ‘Beetle’ at z = 0.103) with unambiguous evidence for active galactic nucleus (AGN) radio-induced feedback acting across a total extension of ∼46 kpc and up to ∼26 kpc from the AGN. To the best of our knowledge, this is the first radio-quiet system where radio-induced feedback has been securely identified at ≫several kpc from the AGN. The morphological, ionization and kinematic properties of the extended ionized gas are correlated with the radio structures. We find along the radio axis (a) enhancement of the optical line emission at the location of the radio hotspots (b) turbulent gas kinematics (FWHM ∼ 380–470 km s−1) across the entire spatial range circumscribed by them (c) ionization minima for the turbulent gas at the location of the hot spots, (d) high temperature Te ≳ 1.9 × 104 K at the NE hotspot. Turbulent gas is also found far from the radio axis, ∼25 kpc in the perpendicular direction. We propose a scenario in which the radio structures have perforated the interstellar medium of the galaxy and escaped into the circumgalactic medium. While advancing, they have interacted with in situ gas modifying its properties. Our results show that jets of modest power can be the dominant feedback mechanism acting across huge volumes in radio-quiet systems, including highly accreting luminous AGNs, where radiative mode feedback may be expected
Risk and Prognostic Factors in Very Old Patients with Sepsis Secondary to Community-Acquired Pneumonia
Background: Little is known about risk and prognostic factors in very old patients developing sepsis secondary to community-acquired pneumonia (CAP). Methods: We conducted a retrospective observational study of data prospectively collected at the Hospital Clinic of Barcelona over a 13-year period. Consecutive patients hospitalized with CAP were included if they were very old (≥80 years) and divided into those with and without sepsis for comparison. Sepsis was diagnosed based on the Sepsis-3 criteria. The main clinical outcome was 30-day mortality. Results: Among the 4219 patients hospitalized with CAP during the study period, 1238 (29%) were very old. The prevalence of sepsis in this age group was 71%. Male sex, chronic renal disease, and diabetes mellitus were independent risk factors for sepsis, while antibiotic therapy before admission was independently associated with a lower risk of sepsis. Thirty-day and intensive care unit (ICU) mortality did not differ between patients with and without sepsis. In CAP-sepsis group, chronic renal disease and neurological disease were independent risk factors for 30-day mortality. Conclusion: In very old patients hospitalized with CAP, in-hospital and 1-year mortality rates were increased if they developed sepsis. Antibiotic therapy before hospital admission was associated with a lower risk of sepsis
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