13,024 research outputs found
Oxygen Absorption in Cooling Flows
The inhomogeneous cooling flow scenario predicts the existence of large
quantities of gas in massive elliptical galaxies, groups, and clusters that
have cooled and dropped out of the flow. Using spatially resolved, deprojected
X-ray spectra from the ROSAT PSPC we have detected strong absorption over
energies ~0.4-0.8 keV intrinsic to the central ~1 arcmin of the galaxy, NGC
1399, the group, NGC 5044, and the cluster, A1795. These systems have amongst
the largest nearby cooling flows in their respective classes and low Galactic
columns. Since no excess absorption is indicated for energies below ~0.4 keV
the most reasonable model for the absorber is warm, collisionally ionized gas
with T=10^{5-6} K where ionized states of oxygen provide most of the
absorption. Attributing the absorption only to ionized gas reconciles the large
columns of cold H and He inferred from Einstein and ASCA with the lack of such
columns inferred from ROSAT, and also is consistent with the negligible atomic
and molecular H inferred from HI, and CO observations of cooling flows. The
prediction of warm ionized gas as the product of mass drop-out in these and
other cooling flows can be verified by Chandra, XMM, and ASTRO-E.Comment: 4 pages (2 figures), Accepted for publication in ApJ Letters, no
significant changes from previous submitted versio
PROTOCOL: A Scoping Review of Graduate Student Education, Curriculum Impact, and Interest in Interdisciplinary Research Training
Title: PROTOCOL: A Scoping Review of Graduate Student Education, Curriculum Impact, and Interest in Interdisciplinary Research Training
Background: Alongside traditional graduate education practices, implementing curriculum focused on providing interdisciplinary research training to graduate students may help support their academic development. This additional educational focus can bolster graduate student understanding of methodological practices, develop alternative routes of thinking or approaching a problem/ issue/ topic, may assist in developing student professional socialization skills, and may positively impact student internal motivations, beliefs, and perceptions.
Methods: Our scoping review protocol was developed a priori utilizing the Joanna Briggs Institute guidance, by Peters et al., and supplemented by a scoping review conducted by Tricco et al. This study will utilize the University of Mississippi Libraries’ (UML) ‘One Search’ for all literature searches conducted under this protocol. Article searches will utilize a set list of search terms for information exploration. These terms will include ‘interdisciplinary,’ ‘graduate,’ ‘education,’ ‘higher education,’ ‘training,’ ‘research,’ ‘implementation,’ ‘successful,’ ‘unsuccessful,’ ‘motivation,’ ‘knowledge,’ and ‘interest.’ All searches will include the ‘interdisciplinary’ search term. All searches will use at least two additional search terms, added using ‘AND’ Boolean logic statements. Articles will meet the inclusion criteria if they are available as a full text, are peer reviewed, are published in a scholarly journal, are published in English, and were published between January 1st, 2000, and December 31st, 2020. All study designs will meet the inclusion criteria. Exclusion criteria will be met if an article is published in a language other than English. We will not be appraising the quality of included articles as recommended by Peters et al. and Tricco et al
Climate-Induced Forest Dieback as an Emergent Global Phenomenon
An organized oral session at the annual meeting of the Ecological Society of America in San Jose, Calif., posed this question: Is climate-induced drought stress triggering increasing rates and unusual patterns of forest die-off at a global scale? Twenty-nine researchers representing five continents reported on patterns, mechanisms, and projections of forest mortality
Consistency conditions for regulatory analysis of financial institutions: a comparison of frontier efficiency methods
We propose a set of consistency conditions that frontier efficiency measures should meet to be most useful for regulatory analysis or other purposes. The efficiency estimates should be consistent in their efficiency levels, rankings, and identification of best and worst firms, consistent over time and with competitive conditions in the market, and consistent with standard nonfrontier measures of performance. We provide evidence on these conditions by evaluating and comparing efficiency estimates on U.S. bank efficiency from variants of all four of the major approaches -- DEA, SFA, TFA, and DFA -- and find mixed results.Financial institutions ; Bank supervision
Coarse-grained simulation of amphiphilic self-assembly
We present a computer simulation study of amphiphilic self assembly performed using a computationally efficient single-site model based on Gay-Berne and Lennard-Jones particles. Molecular dynamics simulations of these systems show that free self-assembly of micellar, bilayer and inverse micelle arrangements can be readily achieved for a single model parameterisation. This self-assembly is predominantly driven by the anisotropy of the amphiphile-solvent interaction, amphiphile-amphiphile interactions being found to be of secondary importance. While amphiphile concentration is the main determinant of phase stability, molecular parameters such as headgroup size and interaction strength also have measurable affects on system properties. </p
Reinventing how pharmacy educators connect as a community
© Pharmacy of Colleges of Association American 2020. The onset of the novel coronavirus (COVID-19) pandemic has added a new layer of complexity to an already difficult period for academic pharmacy. The need to follow social-distancing guidelines has resulted in rapid adoption of technology-enabled communication strategies. While these technologies provide unprecedented ways in which we can connect as an academic community, we must consider their effectiveness in not only promoting exchange of information, but also creating inspiration within the community and supporting the level of interdependence required to tackle the difficult challenges that lie ahead. As the connecting body within the community of pharmacy education, it is incumbent on the American Association of Colleges of Pharmacy (AACP) to consider how we will adapt during this period of disruption. We must adopt new strategies that will allow our members to connect in new, meaningful ways, ways that stimulate ideas, new partnerships, and an overall sense of hope for our future
Grain-boundary grooving and agglomeration of alloy thin films with a slow-diffusing species
We present a general phase-field model for grain-boundary grooving and
agglomeration of polycrystalline alloy thin films. In particular, we study the
effects of slow-diffusing species on grooving rate. As the groove grows, the
slow species becomes concentrated near the groove tip so that further grooving
is limited by the rate at which it diffuses away from the tip. At early times
the dominant diffusion path is along the boundary, while at late times it is
parallel to the substrate. This change in path strongly affects the
time-dependence of grain boundary grooving and increases the time to
agglomeration. The present model provides a tool for agglomeration-resistant
thin film alloy design. keywords: phase-field, thermal grooving, diffusion,
kinetics, metal silicidesComment: 4 pages, 6 figure
Fake News and Indifference to Truth
State of the Union Addresses (SOUA) by two recent US Presidents, President
Obama (2016) and President Trump (2018), and a series of recent of tweets by
President Trump, are analysed by means of the data mining technique, sentiment
analysis. The intention is to explore the contents and sentiments of the
messages contained, the degree to which they dier, and their potential implications
for the national mood and state of the economy. President Trump's 2018
SOUA and his sample tweets are identied as being more positive in sentiment
than President Obama's 2016 SOUA. This is conrmed by bootstrapped t tests
and non-parametric sign tests on components of the respective sentiment scores.
The issue of whether overly positive pronouncements amount to self-promotion,
rather than intrinsic merit or sentiment, is a topic for future research
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