1,833 research outputs found
What can we learn on public accountability from non-health disciplines: a meta-narrative review.
OBJECTIVE: In health, accountability has since long been acknowledged as a central issue, but it remains an elusive concept. The literature on accountability spans various disciplines and research traditions, with differing interpretations. There has been little transfer of ideas and concepts from other disciplines to public health and global health. In the frame of a study of accountability of (international) non-governmental organisations in local health systems, we carried out a meta-narrative review to address this gap. Our research questions were: (1) What are the main approaches to accountability in the selected research traditions? (2) How is accountability defined? (3) Which current accountability approaches are relevant for the organisation and regulation of local health systems and its multiple actors? SETTING: The search covered peer-reviewed journals, monographs and readers published between 1992 and 2012 from political science, public administration, organisational sociology, ethics and development studies. 34 papers were selected and analysed. RESULTS: Our review confirms the wide range of approaches to the conceptualisation of accountability. The definition of accountability used by the authors allows the categorisation of these approaches into four groups: the institutionalist, rights-based, individual choice and collective action group. These four approaches can be considered to be complementary. CONCLUSIONS: We argue that in order to effectively achieve public accountability, accountability strategies are to be complementary and synergistic
The dynamic atmospheres of Mira stars: comparing the CODEX models to PTI time series of TU And
Our comprehension of stellar evolution on the AGB still faces many
difficulties. To improve on this, a quantified understanding of large-amplitude
pulsator atmospheres and interpretation in terms of their fundamental stellar
parameters are essential. We wish to evaluate the effectiveness of the recently
released CODEX dynamical model atmospheres in representing M-type Mira
variables through a confrontation with the time-resolved spectro-photometric
and interferometric PTI data set of TU And. We calibrated the interferometric
K-band time series to high precision. This results in 50 nights of
observations, covering 8 subsequent pulsation cycles. At each phase, the flux
at 2.2m is obtained, along with the spectral shape and visibility points
in 5 channels across the K-band. We compared the data set to the relevant
dynamical, self-excited CODEX models. Both spectrum and visibilities are
consistently reproduced at visual minimum phases. Near maximum, our
observations show that the current models predict a photosphere that is too
compact and hot, and we find that the extended atmosphere lacks H2O opacity.
Since coverage in model parameter space is currently poor, more models are
needed to make firm conclusions on the cause of the discrepancies. We argue
that for TU And, the discrepancy could be lifted by adopting a lower value of
the mixing length parameter combined with an increase in the stellar mass
and/or a decrease in metallicity, but this requires the release of an extended
model grid.Comment: 5 pages, 5 figures, accepted for publication in A&A Letter
Outbursts of EX Hydrae Revisited
We present optical spectroscopy of EX Hya during its 1991 outburst. This
outburst is characterised by strong irradiation of the front face of the
secondary star by the white dwarf, an overflowing stream which is seen strongly
in HeII and by a dip in the light curves, which extends from 0.1-0.6 in the
binary and spin phases. Strong irradiation of the accretion curtain and that of
the inner regions of the disc led to strong emission of HeII and to the
suppression of the Hg and Hb emission.
Disc overflow was observed in quiescence in earlier studies, where the
overflow stream material was modulated at high velocities close to 1000 km/s.
In outburst, the overflowing material is modulated at even higher velocities
(~1500 km/s). These are streaming velocities down the field lines close to the
white dwarf. Evidence for material collecting near the outer edge of the disc
and corotating with the accretion curtain was observed. In decline, this
material and the accretion curtain obscured almost all the emission near binary
phase 0.4, causing a dip. The dip minimum nearly corresponds with spin pulse
minimum. This has provided additional evidence for an extended accretion
curtain, and for the corotation of material with the accretion curtain at the
outer edge of the disc. From these observations we suggest that a mechanism
similar to that of Spruit & Taam, where outbursts result due to the storage and
release of matter outside the magnetosphere, triggers the outbursts of EX Hya.
This is followed by the irradiation of the secondary star due to accretion
induced radiation.Comment: 12 pages, 14 figures, 1 table. Figures 6, 7, 8 and 11 at low
resolution. Paper accepted by the Monthly Notices of the Royal Astronomical
Societ
Direct Measurement of the Radius and Density of the Transiting Exoplanet HD 189733B with the CHARA Array
We have measured the angular diameter of the transiting extrasolar planet
host star HD 189733 using the CHARA O/IR interferometric array. Combining our
new angular diameter of 0.377+/-0.024 mas with the Hipparcos parallax leads to
a linear radius for the host star of 0.779+/-0.052 Rsol and a radius for the
planet of 1.19+/-0.08 RJup. Adopting the mass of the planet as derived by its
discoverers, we derive a mean density of the planet of 0.91+/-0.18 g cm-3. This
is the first determination of the diameter of an extrasolar planet through
purely direct means.Comment: 14 pages, 5 figures, to be published in Astrophysical Journal Letter
Simulation and Training of Gynaecological Skills
In order to offer our patients, the "state of the art" treatment in gynaecology, we need a structured teaching program for trainees concerning the gynaecological skills. In recent years, training and education in endoscopic surgery has been critically reviewed. Clinicians, both surgeons as gynaecologists who perform endoscopic surgery without proper training of the specific psychomotor skills, are at higher risk to increased patient morbidity and mortality. The traditional apprentice-tutor model is no longer valid for developing all skills necessary in gynaecological surgery, particularly in endoscopy. Endoscopic training should happen at both the theoretical and the practical skill level. The acquisition of the correct knowledge regarding general laparoscopy, hysteroscopy and standard level procedures is as important as learning the necessary psychomotor skills to successfully perform endoscopic manipulations. Training in the operating room can only start when it is proven that knowledge and skills are present. To learn and train total abdominal hysterectomy by laparotomy there are inexpensive simple models that can be used, which are easy to reproduce. The development, construction, cost, and utility of a low-cost and anatomically representative vaginal hysterectomy simulator also has been described. The complexity of modern surgery has increased the demands and challenges to surgical education and the quality control.info:eu-repo/semantics/publishedVersio
Fundamental Properties of Cool Stars with Interferometry
We present measurements of fundamental astrophysical properties of nearby,
low-mass, K- and M-dwarfs from our DISCOS survey (DIameterS of COol Stars). The
principal goal of our study is the determination of linear radii and effective
temperatures for these stars. We calculate their radii from angular diameter
measurements using the CHARA Array and Hipparcos distances. Combined with
bolometric flux measurements based on literature photometry, we use our angular
diameter results to calculate their effective surface temperatures. We present
preliminary results established on an assortment of empirical relations to the
stellar effective temperature and radius that are based upon these
measurements. We elaborate on the discrepancy seen between theoretical and
observed stellar radii, previously claimed to be related to stellar activity
and/or metallicity. Our preliminary conclusion, however, is that convection
plays a larger role in the determination of radii of these late-type stars.
Understanding the source of the radius disagreement is likely to impact other
areas of study for low-mass stars, such as the detection and characterization
of extrasolar planets in the habitable zones.Comment: Contribution to Proceedings of Cool Stars 16 Workshop; 8 pages in ASP
format; 9 figure
A new interferometric study of four exoplanet host stars : {\theta} Cygni, 14 Andromedae, {\upsilon} Andromedae and 42 Draconis
Studying exoplanet host stars is of the utmost importance to establish the
link between the presence of exoplanets around various types of stars and to
understand the respective evolution of stars and exoplanets.
Using the limb-darkened diameter (LDD) obtained from interferometric data, we
determine the fundamental parameters of four exoplanet host stars. We are
particularly interested in the F4 main-sequence star, {\theta} Cyg, for which
Kepler has recently revealed solar-like oscillations that are unexpected for
this type of star. Furthermore, recent photometric and spectroscopic
measurements with SOPHIE and ELODIE (OHP) show evidence of a quasi-periodic
radial velocity of \sim150 days. Models of this periodic change in radial
velocity predict either a complex planetary system orbiting the star, or a new
and unidentified stellar pulsation mode.
We performed interferometric observations of {\theta} Cyg, 14 Andromedae,
{\upsilon} Andromedae and 42 Draconis for two years with VEGA/CHARA (Mount
Wilson, California) in several three-telescope configurations. We measured
accurate limb darkened diameters and derived their radius, mass and temperature
using empirical laws.
We obtain new accurate fundamental parameters for stars 14 And, {\upsilon}
And and 42 Dra. We also obtained limb darkened diameters with a minimum
precision of \sim 1.3%, leading to minimum planet masses of Msini=5.33\pm 0.57,
0.62 \pm 0.09 and 3.79\pm0.29 MJup for 14 And b, {\upsilon} And b and 42 Dra b,
respectively. The interferometric measurements of {\theta} Cyg show a
significant diameter variability that remains unexplained up to now. We propose
that the presence of these discrepancies in the interferometric data is caused
by either an intrinsic variation of the star or an unknown close companion
orbiting around it.Comment: 10 pages + 2 pages appendix, 16 figures, accepted for publication in
A&
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