574 research outputs found
A shortage of health information management professionals: How would we know?
The introduction of computers, the expansion of health insurance coverage through employers and government programs, and the increased use of personal health information have created a demand for a new breed of qualified medical record and health information personnel. The health information management workforce, which is entrusted with accurately coding, maintaining, storing, managing, analyzing, and disseminating all personal health information created from health care encounters, is reportedly in short supply. Given the complexity in defining and enumerating the profession, it is challenging to determine if such a shortage exists. There is a lack of uniformity across scope of practice, job titles, educational paths, and credentials. We report selected findings from a study of the health information management profession in North Carolina illustrating the methodologic problems encountered when measuring the supply and demand of this workforce. A case is made that greater standardization across these multiple facets of the profession would be beneficial to the workforce, and we offer recommendations on how this could be accomplished
Generalised discrete torsion and mirror symmetry for G_2 manifolds
A generalisation of discrete torsion is introduced in which different
discrete torsion phases are considered for the different fixed points or twist
fields of a twisted sector. The constraints that arise from modular invariance
are analysed carefully. As an application we show how all the different
resolutions of the T^7/Z_2^3 orbifold of Joyce have an interpretation in terms
of such generalised discrete torsion orbifolds. Furthermore, we show that these
manifolds are pairwise identified under G_2 mirror symmetry. From a conformal
field theory point of view, this mirror symmetry arises from an automorphism of
the extended chiral algebra of the G_2 compactification.Comment: LaTeX, 25 pages, 1 figure; v2: one reference added and comment about
higher loop modular invariance corrected, version to be publishe
Neutral Plasma Oscillations at Zero Temperature
We use cold plasma theory to calculate the response of an ultracold neutral
plasma to an applied rf field. The free oscillation of the system has a
continuous spectrum and an associated damped quasimode. We show that this
quasimode dominates the driven response. We use this model to simulate plasma
oscillations in an expanding ultracold neutral plasma, providing insights into
the assumptions used to interpret experimental data [Phys. Rev. Lett. 85, 318
(2000)].Comment: 4.3 pages, including 3 figure
Family Unification in Five and Six Dimensions
In family unification models, all three families of quarks and leptons are
grouped together into an irreducible representation of a simple gauge group,
thus unifying the Standard Model gauge symmetries and a gauged family symmetry.
Large orthogonal groups, and the exceptional groups and have been
much studied for family unification. The main theoretical difficulty of family
unification is the existence of mirror families at the weak scale. It is shown
here that family unification without mirror families can be realized in simple
five-dimensional and six-dimensional orbifold models similar to those recently
proposed for SU(5) and SO(10) grand unification. It is noted that a family
unification group that survived to near the weak scale and whose coupling
extrapolated to high scales unified with those of the Standard model would be
evidence accessible in principle at low energy of the existence of small
(Planckian or GUT-scale) extra dimensions.Comment: 13 pages, 2 figures, minor corrections, references adde
Quantum corrections to the ground state energy of a trapped Bose-Einstein condensate: A diffusion Monte Carlo calculation
The diffusion Monte Carlo method is applied to describe a trapped atomic
Bose-Einstein condensate at zero temperature, fully quantum mechanically and
nonperturbatively. For low densities, [n(0): peak
density, a: s-wave scattering length], our calculations confirm that the exact
ground state energy for a sum of two-body interactions depends on only the
atomic physics parameter a, and no other details of the two-body model
potential. Corrections to the mean-field Gross-Pitaevskii energy range from
being essentially negligible to about 20% for N=2-50 particles in the trap with
positive s-wave scattering length a=100-10000 a.u.. Our numerical calculations
confirm that inclusion of an additional effective potential term in the
mean-field equation, which accounts for quantum fluctuations [see e.g. E.
Braaten and A. Nieto, Phys. Rev. B 56}, 14745 (1997)], leads to a greatly
improved description of trapped Bose gases.Comment: 7 pages, 4 figure
Dynamic input demand functions and resource adjustment for US agriculture: state evidence
The paper presents an econometric model of dynamic agricultural input demand functions that include research based technical change and autoregressive disturbances and fits the model to annual data for a set of state aggregates pooled over 1950â1982. The methodological approach is one of developing a theoretical foundation for a dynamic input demand system and accepting state aggreage behavior as approximated by nonlinear adjustment costs and long-term profit maximization. Although other studies have largely ignored autocorrelation in dynamic input demand systems, the results show shorter adjustment lags with autocorrelation than without. Dynamic input demand own-price elasticities for the six input groups are inelastic, and the demand functions possess significant cross-price and research effects
Extrapolating SMBH correlations down the mass scale: the case for IMBHs in globular clusters
Empirical evidence for both stellar mass black holes M_bh<10^2 M_sun) and
supermassive black holes (SMBHs, M_bh>10^5 M_sun) is well established.
Moreover, every galaxy with a bulge appears to host a SMBH, whose mass is
correlated with the bulge mass, and even more strongly with the central stellar
velocity dispersion sigma_c, the `M-sigma' relation. On the other hand,
evidence for "intermediate-mass" black holes (IMBHs, with masses in the range
1^2 - 10^5 M_sun) is relatively sparse, with only a few mass measurements
reported in globular clusters (GCs), dwarf galaxies and low-mass AGNs. We
explore the question of whether globular clusters extend the M-sigma
relationship for galaxies to lower black hole masses and find that available
data for globular clusters are consistent with the extrapolation of this
relationship. We use this extrapolated M-sigma relationship to predict the
putative black hole masses of those globular clusters where existence of
central IMBH was proposed. We discuss how globular clusters can be used as a
constraint on theories making specific predictions for the low-mass end of the
M-sigma relation.Comment: 14 pages, 3 figures, accepted for publication in Astrophysics and
Space Science; fixed typos and a quote in Sec.
Project manager-to-project allocations in practice: an empirical study of the decision-making practices of a multi-project based organization
Empirical studies that examine how managers make project manager-to-project (PM2P) allocation decisions in multi-project settings are currently limited. Such decisions are crucial to organizational success. An empirical study of the PM2P practice, conducted in the context of Botswana, revealed ineffective processes in terms of optimality in decision-making. A conceptual model to guide effective PM2P practices was developed. The focus of this study is on deploying the model as a lens to study the PM2P practices of a large organization, with a view to identify and illustrate strengths and weaknesses. A case study was undertaken in the mining industry, where core activities in terms of projects are underground mineral explorations at identified geographical regions. A semi-structured interview protocol was used to collect data from 15 informants, using an enumeration. Integrated analysis of both data types (using univariate descriptive analysis for the quantitative data, content and thematic analysis for the qualitative data) revealed strengths in PM2P practices, demonstrated by informantsâ recognition of some important criteria to be considered. The key weaknesses were exemplified by a lack of effective management tools and techniques to match project managers to projects. The findings provide a novel perspective through which improvements in working practices can be made
Proximity effect at superconducting Sn-Bi2Se3 interface
We have investigated the conductance spectra of Sn-Bi2Se3 interface junctions
down to 250 mK and in different magnetic fields. A number of conductance
anomalies were observed below the superconducting transition temperature of Sn,
including a small gap different from that of Sn, and a zero-bias conductance
peak growing up at lower temperatures. We discussed the possible origins of the
smaller gap and the zero-bias conductance peak. These phenomena support that a
proximity-effect-induced chiral superconducting phase is formed at the
interface between the superconducting Sn and the strong spin-orbit coupling
material Bi2Se3.Comment: 7 pages, 8 figure
Toward an internally consistent astronomical distance scale
Accurate astronomical distance determination is crucial for all fields in
astrophysics, from Galactic to cosmological scales. Despite, or perhaps because
of, significant efforts to determine accurate distances, using a wide range of
methods, tracers, and techniques, an internally consistent astronomical
distance framework has not yet been established. We review current efforts to
homogenize the Local Group's distance framework, with particular emphasis on
the potential of RR Lyrae stars as distance indicators, and attempt to extend
this in an internally consistent manner to cosmological distances. Calibration
based on Type Ia supernovae and distance determinations based on gravitational
lensing represent particularly promising approaches. We provide a positive
outlook to improvements to the status quo expected from future surveys,
missions, and facilities. Astronomical distance determination has clearly
reached maturity and near-consistency.Comment: Review article, 59 pages (4 figures); Space Science Reviews, in press
(chapter 8 of a special collection resulting from the May 2016 ISSI-BJ
workshop on Astronomical Distance Determination in the Space Age
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