4,801 research outputs found
International workshop on Time-Variable Phenomena in the Jovian System
Many of the scientifically interesting phenomena that occur in the Jovian system are strongly time variable. Some are episodic (e.g., Io volcanism); some are periodic (wave transport in Jupiters atmosphere); and some are exceedingly complex (magnetosphere - Io - Torus-Auroral interactions) and possibly unstable. To investigate this class of phenomena utilizing Voyager data and, in the future, Galileo results, a coherent program of ground based and earth-orbital observations, and of theory that spans the time between the missions, is required. To stimulate and help define the basis of such a scientific program researchers organized an International Workshop on the subject with the intent of publishing the proceedings which would represent the state of knowledge in 1987
Non-thermal X-ray Emission: An Alternative to Cluster Cooling Flows?
We report the results of experiments aimed at reducing the major problem with
cooling flow models of rich cluster X-ray sources: the fact that most of the
cooled gas or its products have not been found. Here we show that much of the
X-ray emission usually attributed to cooling flows can, in fact, be modeled by
a power-law component which is indicative of a source(s) other than thermal
bremsstrahlung from the intracluster medium. We find that adequate simultaneous
fits to ROSAT PSPCB and ASCA GIS/SIS spectra of the central regions of ten
clusters are obtained for two-component models that include a thermal plasma
component that is attributable to hot intracluster gas and a power-law
component that is likely generated by compact sources and/or extended
non-thermal emission. For five of the clusters that purportedly have massive
cooling flows, the best-fit models have power-law components that contribute
30 % of the total flux (0.14 - 10.0 keV) within the central 3
arcminutes. Because cooling flow mass deposition rates are inferred from X-ray
fluxes, our finding opens the possibility of significantly reducing cooling
rates.Comment: 11 pages, 3 figures, emulateapj style. Accepted for publication in
Ap
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The constitutional rights of college students : the principles of the first, fourth, and fourteenth amendments as they apply to higher education.
The impact of an innovative human resource function on firm performance: the moderating role of financing strategy
The current study examined the impact of the human resource function and financing strategy on the financial performance of 104 UK manufacturing firms. Hypotheses are drawn from a resource-based perspective on human resource management and a financial theory perspective on capital structure. Results show that an innovative HR function is significantly related to economic performance. However, the relationship between an innovative HR function and economic performance was moderated by the firm¿s financing strategy. Firms obtained higher returns from an innovative HR function when pursuing a low leveraging (debt) financing strategy, a finding consistent with modern finance theory notions that firmspecific strategic assets provide greatest value when financed primarily through equity as opposed to debt
Galaxy Orientations in the Coma Cluster
We have examined the orientations of early-type galaxies in the Coma cluster
to see whether the well-established tendency for brightest cluster galaxies to
share the same major axis orientation as their host cluster also extends to the
rest of the galaxy population. We find no evidence of any preferential
orientations of galaxies within Coma or its surroundings. The implications of
this result for theories of the formation of clusters and galaxies
(particularly the first-ranked members) are discussed.Comment: Accepted for publication in the Astrophysical Journal Letters. 4
pages, 4 figure
Illusions of team working in health care
Purpose: The ubiquity and value of teams in healthcare are well acknowledged. However, in practice, healthcare teams vary dramatically in their structures and effectiveness in ways that can damage team processes and patient outcomes. The aim of this paper is to highlight these characteristics and to extrapolate several important aspects of teamwork that have a powerful impact on team effectiveness across healthcare contexts. Design/methodology/approach: The paper draws upon the literature from health services management and organisational behaviour to provide an overview of the current science of healthcare teams. Findings: Underpinned by the input-process-output framework of team effectiveness, team composition, team task, and organisational support are viewed as critical inputs that influence key team processes including team objectives, leadership and reflexivity, which in turn impact staff and patient outcomes. Team training interventions and care pathways can facilitate more effective interdisciplinary teamwork. Originality/value: The paper argues that the prevalence of the term "team" in healthcare makes the synthesis and advancement of the scientific understanding of healthcare teams a challenge. Future research therefore needs to better define the fundamental characteristics of teams in studies in order to ensure that findings based on real teams, rather than pseudo-like groups, are accumulated
Teams, HRM and innovation:an organisation-level analysis
For organizations to survive and prosper they have to develop new and improved products, services and ways of working. Innovation is vital for organizational survival. Much research and managerial attention is therefore devoted to understanding the factors that predict innovation in organizations. This paper describes a research study of product innovation in manufacturing organizations and explores the extent to which team based working and team working effectiveness in these organizations predict product innovation. It also considers whether combinations of good HRM systems and practices, extensive team based working and effective team working are associated with product innovation
Dynamical evolution of globular cluster systems in clusters of galaxies I. The case of NGC 1404 in the Fornax cluster
We investigate, via numerical simulations, the tidal stripping and accretion
of globular clusters (GCs). In particular, we focus on creating models that
simulate the situation for the GC systems of NGC 1404 and NGC 1399 in the
Fornax cluster, which have poor (specific frequency 2) and
rich ( 10) GC systems respectively. We initially assign NGC
1404 in our simulation a typical ( 5) for cluster
ellipticals, and find that its GC system can only be reduced through stripping
to the presently observed value, if its orbit is highly eccentric (with orbital
eccentricity of 0.5) and if the initial scale length of the GCs system is
about twice as large as the effective radius of NGC 1404 itself. These stripped
GCs can be said to have formed a `tidal stream' of intracluster globular
clusters (ICGCs) orbiting the centre of Fornax cluster (many of which would be
assigned to NGC 1399 in an imaging study). The physical properties of these GCs
(e.g., number, radial distribution) depend on the orbit and initial
distribution of GCs in NGC 1404. Our simulations also predict a trend for
to rise with increasing clustercentric distance - a trend for which
there is some observational support in the Fornax cluster.Comment: 12 pages 12 figures, MNRAS in pres
The ACS Virgo Cluster Survey XV. The Formation Efficiencies of Globular Clusters in Early-Type Galaxies: The Effects of Mass and Environment
The fraction of stellar mass contained in globular clusters (GCs), also
measured by number as the specific frequency, is a fundamental quantity that
reflects both a galaxy's early star formation and its entire merging history.
We present specific frequencies, luminosities, and mass fractions for the
globular cluster systems of 100 early-type galaxies in the ACS Virgo Cluster
Survey, the largest homogeneous catalog of its kind. We find that 1) GC mass
fractions can be high in both giants and dwarfs, but are universally low in
galaxies with intermediate luminosities. 2) The behavior of specific frequency
across galaxy mass is dominated by the blue GCs. 3) The GC fractions of
low-mass galaxies exhibit a dependence on environment. Nearly all dwarf
galaxies with high GC fractions are within 1 Mpc of the cD galaxy M87,
presenting the first strong evidence that GC formation in dwarfs is biased
toward dense environments. 4) GC formation in central dwarfs is biased because
their stars form earliest and most intensely. Comparisons to the Millennium
Simulation show that central dwarfs have older stellar populations and form
more stars at higher star formation rates (SFRs) and SFR surface densities. The
SFR surface density in simulated dwarfs peaks before the total SFR, naturally
producing GC populations that are older and more metal-poor than the field
stars. 5) Dwarfs within ~40 kpc of the giant ellipticals M87 and M49 are red
and have few or no GCs, suggesting that they have been tidally stripped and
have contributed their GCs to the halos of their giant neighbors. The central
dwarfs with high GC mass fractions are thus likely to be the survivors most
similar to the protogalaxies that assembled the rich M87 globular cluster
system.(Abridged)Comment: 27 pages, 21 figures, 7 tables. Accepted for publication in the
Astrophysical Journa
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