5,456 research outputs found
The determinants of hospital costs : an analysis of Ethiopia
The problem of financing health care in poor countries has become increasingly acute. In the context of health financing, hospitals are viewed with skepticism as facilities are not cost-effective in the provision of primary health care services. Given this view, it is increasingly thought that such institutions should become financially independent from government subsidies and find other ways to finance both their recurrent and capital costs. The purpose of this paper is to analyze the determinants of hospital costs in a poor country by conducting a case study using data from Ethiopia. It analyzes the issues of economies of scale and scope in the delivery of hospital based health care services in a poor country. A translog-like cost function specification is used in the analysis. It shows that the number of inpatient days, deliveries and laboratory exams had a positive and statistically significant effect on total cost. A negative and statistically significant coefficient associated with the output interaction term indicated the existence of economies of scope between the number of inpatient days and the number of first outpatient visits. Finally, the number of total beds in a hospital appeared to have a positive and significant independent effect on total hospital cost.Economic Theory&Research,Business Environment,Business in Development,Environmental Economics&Policies,Health Systems Development&Reform
Structures Produced by the Collision of Extragalactic Jets with Dense Clouds
We have investigated how several parameters can affect the results of a
collision between an extragalactic jet and a dense, intergalactic cloud,
through a series of hydrodynamic simulations. Such collisions are often
suggested to explain the distorted structures of some radio jets. However,
theoretical studies of this mechanism are in conflict over whether it can
actually reproduce the observations.
The parameters are the Mach number, and the relative densities of the jet and
the cloud to the ambient medium. Using a simple prescription we have produced
synthetic radio images for comparison with observations. These show that a
variety of structures may be produced from simple jet-cloud collisions. We
illustrate this with a few examples, and examine the details in one case. In
most cases we do not see a clear, sustained deflection. Lighter jets are
completely disrupted. The most powerful jets produce a hotspot at the impact
which outshines any jet emission and erode the cloud too quickly to develop a
deflected arm. It appears that moderate Mach numbers and density contrasts are
needed to produce bends in the radio structure. This explains the apparent
conflict between theoretical studies, as conclusions were based on different
values of these parameters. Shocks are produced in the ambient medium that
might plausibly reproduce the observed alignment of the extended emission line
regions with the radio axis.Comment: 21 pages, 11 figures. Submitted to MNRAS. Also available in html
version at http://www.doc.mmu.ac.uk/STAFF/S.Higgins/jcmnpaper/jc_mn.htm
Curvature-controlled defect dynamics in active systems
We have studied the collective motion of polar active particles confined to
ellipsoidal surfaces. The geometric constraints lead to the formation of
vortices that encircle surface points of constant curvature (umbilics). We have
found that collective motion patterns are particularly rich on ellipsoids, with
four umbilics where vortices tend to be located near pairs of umbilical points
to minimize their interaction energy. Our results provide a new perspective on
the migration of living cells, which most likely use the information provided
from the curved substrate geometry to guide their collective motion.Comment: Accepted manuscript. 8 pages, 7 Figures. Movies of the motion
patterns can be found at
https://www.youtube.com/playlist?list=PLEsE7_tnqXZ_U258VwxES8KAJTV_eO43
Effect of an in-shed sprinkler cooling system on temperature, relative humidity, water usage, litter conditions, live weight and mortality
This report describes the first Australian trial of a low-pressure, overhead sprinkler system that reduces the need for conventional evaporative cooling pads or high pressure foggers in meat chicken houses
Damped Lyman alpha systems and disk galaxies: number density, column density distribution and gas density
We present a comparison between the observed properties of damped Lyman alpha
systems (DLAs) and the predictions of simple models for the evolution of
present day disk galaxies, including both low and high surface brightness
galaxies. We focus in particular on the number density, column density
distribution and gas density of DLAs, which have now been measured in
relatively large samples of absorbers. From the comparison we estimate the
contribution of present day disk galaxies to the population of DLAs, and how it
varies with redshift. Based on the differences between the models and the
observations, we also speculate on the nature of the fraction of DLAs which
apparently do not arise in disk galaxies.Comment: 11 pages, 10 figures, accepted in MNRA
Anomalous fluctuations in phases with a broken continuous symmetry
It is shown that the Goldstone modes associated with a broken continuous
symmetry lead to anomalously large fluctuations of the zero field order
parameter at any temperature below T_c. In dimensions 2<d<4, the variance of
the extensive spontaneous magnetization scales as L^4 with the system size L,
independent of the order parameter dynamics. The anomalous scaling is a
consequence of the 1/q^{4-d} divergence of the longitudinal susceptibility. For
ground states in two dimensions with Goldstone modes vanishing linearly with
momentum, the dynamical susceptibility contains a singular contribution
(q^2-\omega^2/c^2)^{-1/2}. The dynamic structure factor thus exhibits a
critical continuum above the undamped spin wave pole, which may be detected by
neutron scattering in the N\'eel-phase of 2D quantum antiferromagnets.Comment: final version, minor change
Nanotrapping and the thermodynamics of optical tweezers
Particles that can be trapped in optical tweezers range from tens of microns
down to tens of nanometres in size. Interestingly, this size range includes
large macromolecules. We show experimentally, in agreement with theoretical
expectations, that optical tweezers can be used to manipulate single molecules
of polyethylene oxide suspended in water. The trapped molecules accumulate
without aggregating, so this provides optical control of the concentration of
macromolecules in solution. Apart from possible applications such as the
micromanipulation of nanoparticles, nanoassembly, microchemistry, and the study
of biological macromolecules, our results also provide insight into the
thermodynamics of optical tweezers.Comment: 5 pages, 3 figures, presented at 17th AIP Congress, Brisbane, 200
Magnetopause current as seen by Cluster
The four-spacecraft, magnetic field measurements on Cluster can be combined to produce an accurate determination of the electric current in the magnetopause boundary during stable magnetopause crossings. For events that are planar on the scale of the spacecraft configuration, the thickness of the current layer can be accurately estimated from its magnetic profile at each spacecraft and the corresponding boundary crossing times. The latter, give a determination of boundary motion relative to the Cluster array. We use the estimates of all these properties, for a range of spacecraft separation distances, to show, firstly, that the estimate of electric current density is representative even when the spatial scale of the configuration of Cluster spacecraft approaches the thickness of the current layer. Secondly, we show that the estimated current lies in the plane of the boundary and demonstrate this for crossings occurring during large-scale ripples on the magnetopause. Thirdly, we show that the magnitude of the current is accurately represented, averaged over the extent of the current layer, by comparing to the change in the boundary-parallel magnetic field component divided by the estimated current layer thickness. We demonstrate this last point using a range of crossings each having a different thickness and crossing speed, different changes in the magnetic field component and different current densities
Review of fan efficiency for meat chicken sheds
This report is all about ventilation fans (exhaust fans) used on tunnel ventilated meat chicken sheds. The report has two themes: reviewing the performance and efficiency of new fans currently available in Australia; and identifying methods to assess fans and help to identify fans that are underperforming
- …