1,514 research outputs found
Charting new territory for organizational ethnography: Insights from a team-based video ethnography of reinsurance trading in Lloyd’s of London
Increasing complexity, fragmentation, mobility, pace, and technological intermediation of organizational life make “being there” increasingly difficult. Where do ethnographers have to be, when, for how long, and with whom to “be there” and grasp the practices, norms, and values that make the situation meaningful to natives? These novel complexities call for new forms of organizational ethnography. The purpose of this paper is to discuss the above issues
A Millisecond Interferometric Search for Fast Radio Bursts with the Very Large Array
We report on the first millisecond timescale radio interferometric search for
the new class of transient known as fast radio bursts (FRBs). We used the Very
Large Array (VLA) for a 166-hour, millisecond imaging campaign to detect and
precisely localize an FRB. We observed at 1.4 GHz and produced visibilities
with 5 ms time resolution over 256 MHz of bandwidth. Dedispersed images were
searched for transients with dispersion measures from 0 to 3000 pc/cm3. No
transients were detected in observations of high Galactic latitude fields taken
from September 2013 though October 2014. Observations of a known pulsar show
that images typically had a thermal-noise limited sensitivity of 120 mJy/beam
(8 sigma; Stokes I) in 5 ms and could detect and localize transients over a
wide field of view. Our nondetection limits the FRB rate to less than
7e4/sky/day (95% confidence) above a fluence limit of 1.2 Jy-ms. Assuming a
Euclidean flux distribution, the VLA rate limit is inconsistent with the
published rate of Thornton et al. We recalculate previously published rates
with a homogeneous consideration of the effects of primary beam attenuation,
dispersion, pulse width, and sky brightness. This revises the FRB rate downward
and shows that the VLA observations had a roughly 60% chance of detecting a
typical FRB and that a 95% confidence constraint would require roughly 500
hours of similar VLA observing. Our survey also limits the repetition rate of
an FRB to 2 times less than any known repeating millisecond radio transient.Comment: Submitted to ApJ. 13 pages, 9 figure
Fatal parvoviral myocarditis: A case report and review of literature
This is an Open Access article distributed under the terms of the Creative Commons Attribution Licens
Exploring the Pursuit of Doctoral Education by Nurses Seeking or Intending to Stay in Faculty Roles
The purpose of this study was to describe the factors influencing the pursuit and completion of doctoral education by nurses intending to seek or retain faculty roles. Traditionally, doctoral education evolved to focus on the preparation of nurses to conduct scientific research, primarily through the doctor of philosophy programs. Most recently, the doctor of nursing practice degree emerged and was designed for advanced practice nurses to be clinical leaders who translate research into practice and policy. Nurses who pursue doctoral education in order to assume or maintain faculty roles must choose between these degrees if they desire a doctorate within the discipline; however, factors influencing their decisions and the intended outcomes of their choice are not clear. During this study, 548 nurses (current students or recent graduates of doctoral programs) completed a comprehensive survey to generate critical evidence about the factors influencing the choices made. Principal findings are related to the issues of time, money, and program selection. These findings can be used to develop strategies to increase enrollment and, therefore, the number of doctorally prepared faculty who are specifically prepared to excel as nursing faculty
XO-5b: A Transiting Jupiter-sized Planet With A Four Day Period
The star XO-5 (GSC 02959-00729, V=12.1, G8V) hosts a Jupiter-sized,
Rp=1.15+/-0.12 Rjup, transiting extrasolar planet, XO-5b, with an orbital
period of P=4.187732+/-0.00002 days. The planet mass (Mp=1.15+/-0.08 Mjup) and
surface gravity (gp=22+/-5 m/s^2) are significantly larger than expected by
empirical Mp-P and Mp-P-[Fe/H] relationships. However, the deviation from the
Mp-P relationship for XO-5b is not large enough to suggest a distinct type of
planet as is suggested for GJ 436b, HAT-P-2b, and XO-3b. By coincidence XO-5
overlies the extreme H I plume that emanates from the interacting galaxy pair
NGC 2444/NGC 2445 (Arp 143).Comment: 10 pages, 9 Figures, Submitted to Ap
Measuring Transit Signal Recovery in the Kepler Pipeline. III. Completeness of the Q1-Q17 DR24 Planet Candidate Catalogue, with Important Caveats for Occurrence Rate Calculations
With each new version of the Kepler pipeline and resulting planet candidate
catalogue, an updated measurement of the underlying planet population can only
be recovered with an corresponding measurement of the Kepler pipeline detection
efficiency. Here, we present measurements of the sensitivity of the pipeline
(version 9.2) used to generate the Q1-Q17 DR24 planet candidate catalog
(Coughlin et al. 2016). We measure this by injecting simulated transiting
planets into the pixel-level data of 159,013 targets across the entire Kepler
focal plane, and examining the recovery rate. Unlike previous versions of the
Kepler pipeline, we find a strong period dependence in the measured detection
efficiency, with longer (>40 day) periods having a significantly lower
detectability than shorter periods, introduced in part by an incorrectly
implemented veto. Consequently, the sensitivity of the 9.2 pipeline cannot be
cast as a simple one-dimensional function of the signal strength of the
candidate planet signal as was possible for previous versions of the pipeline.
We report on the implications for occurrence rate calculations based on the
Q1-Q17 DR24 planet candidate catalog and offer important caveats and
recommendations for performing such calculations. As before, we make available
the entire table of injected planet parameters and whether they were recovered
by the pipeline, enabling readers to derive the pipeline detection sensitivity
in the planet and/or stellar parameter space of their choice.Comment: 8 pages, 5 figures, full electronic version of Table 1 available at
the NASA Exoplanet Archive; accepted by ApJ May 2nd, 201
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