108 research outputs found
Heuristics and political accountability in complex governance: An experimental test:
A growing body of empirical work suggests that identifying the actors formally tasked with implementing policy can focus attention away from incumbent politicians. We examine the effects on blame attribution and voting intention of (a) the identifiability of a responsible policy worker (administrator), and (b) the evaluability of the policy work or outcome (policy failure), in the context of programs at two federal agencies (loans by the Small Business Administration and inspections by the U.S. Department of Agriculture). Using a set of online survey experiments with 1105 US adults, we find that the evaluability of a (negative) outcome generally reduces voting intention, but that the identifiability of a policy worker (administrator) tends to shift blame away from the incumbent politician and thus to increase voting intention. These experimental findings provide at least partial support for our theoretical expectations
How Brexit can give Scotland, Wales and Northern Ireland more policymaking power
As the result of last week's election begins to sink in, one thing on the minds of politicians in Scotland, Wales and Northern Ireland is the fate of devolved authority after Brexit. Anthony M. Bertelli (Bocconi and Penn State) asks how Brexit can give them more policymaking power. Prime Minister Boris Johnson endorsed devolved authority during a September trip to Scotland: âWe are going to maximise the power of the North. And we are going to make sure that it is people here who are in control over the things that matter to them.â Michael Russell, Scotlandâs Secretary for Government Business and Constitutional Relations, saw things differently. He claimed that Westminster is âdeterminedâ to roll back devolution in favour of a âmore centralised state.
An agenda for the study of Public Administration in Developing Countries
Developing nations demand a different scholarly approach in the field of public administration. We advance an agenda for research that stands on four pillars. First, in the absence of easily accessible data scholars of developing world public administration must assemble it for themselves. Second, building and testing theory plays a paramount role because researchers face limited information. Third, in developing countries, multiânational and nonâgovernmental organizations are often crucial and must be considered in studying public administration. Fourth, given the novelties and ambiguities researchers face, qualitative information must be integrated throughout the research process. Our articleâand the articles in this volumeâconstitute a call for developing country research to contribute to the study of public administration writ large, informing our understanding of both developing and developed states.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/162699/2/gove12520_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/162699/1/gove12520.pd
Stellar Evolutionary Models for Magellanic Clouds
We supplement current evolutionary computations concerning Magellanic Cloud
stars by exploring the evolutionary behavior of canonical stellar models
(i.e.,with inefficient core overshooting) with metallicities suitable for stars
in the Clouds. After discussing the adequacy of the adopted evolutionary
scenario, we present evolutionary sequences as computed following a selected
sample of stellar models in the mass range 0.8-8 Mo from the Main Sequence till
the C ignition or the onset of thermal pulses in the advanced Asymptotic Giant
Branch phase. On this basis, cluster isochrones covering the range of ages from
100 Myr to 15 Gyr are presented and discussed. To allow a comparison with
evolutionary investigations appeared in the recent literature, we computed
additional sets of models which take into account moderate core overshooting
during the H burning phase, discussing the comparison in terms of current
uncertainties in the stellar evolutionary models. Selected predictions
constraining the cluster ages are finally discussed, presenting a calibration
of the difference in magnitude between the luminous MS termination and the He
burning giants in terms of cluster age. Both evolutionary tracks and isochrones
have been made available at the node http://gipsy.cjb.net as a first step of a
planned ``Pisa Evolutionary Library''.Comment: 11 pages, 9 eps figures, A&A accepted, evolutionary tracks and
isochrones available at http://gipsy.cjb.net at the link ``Pisa Evolutionary
Library'
An empirical test of the theoretical population corrections to the Red Clump absolute magnitude
The mean absolute magnitude of the local red clump (RC) is a very well
determined quantity due to the availability of accurate HIPPARCOS parallaxes
for several hundred RC stars, potentially allowing it to be used as an accurate
extra-galactic distance indicator. Theoretical models predict that the RC mean
magnitude has non-linear dependencies on both age and metallicity. This
suggests that a population correction, based on the star formation rate (SFR)
and age-metallicity relation (AMR) of a particular system, should be applied to
the local RC magnitude before it can be compared to the RC in that system in
order to make a meaningful distance determination. Using a sample of 8 Galactic
open clusters and the GC 47 Tuc, we determine the cluster distances, and hence
the RC absolute magnitude in V, I and K, by applying our empirical main
sequence fitting method, which utilizes a large sample of local field dwarfs
with accurate HIPPARCOS parallaxes. The age and metallicity range of these 9
clusters enable us to make a quantitative assessment of the age and metallicity
dependencies of the population corrections predicted by the theoretical models
of Girardi & Salaris (2001). We find excellent agreement between the empirical
data and the models in all 3 pass-bands, with no statistically significant
trends or offsets, thus fully confirming the applicability of the models to
single-age, single-metallicity stellar populations. Since, from the models, the
population correction is a complicated function of both metallicity and age, if
this method is used to derive distances to composite populations, it is
essential to have an accurate assessment of the SFR and AMR of the system in
question, if errors of several tenths of a magnitude are to be avoided.Comment: 9 pages, 5 figures. MNRAS accepte
Wide Field Photometry of the Galactic Globular Cluster M22
We present wide field photometry of the Galactic Globular Cluster M~22 in the
B, V and I passbands for more than 186,000 stars. The study is complemented by
the photometry in two narrowband filters centered on H and the
adjacent continuum, and by infrared J, H and K magnitudes derived from the 2
MASS survey for 2000 stars. Profiting from this huge database, we
completely characterized the evolved stellar sequences of the cluster by
determining a variety of photometric parameters, including new photometric
estimates of the mean metallicity, reddening and distance to the cluster. In
particular, from our multi-wavelength analysis, we re-examined the
long-standing metallicity spread problem in M~22. According to our dataset, we
conclude that most of the observed width of the red giant branch must be due to
differential reddening, which amounts to a maximum of , although the presence of a small metallicity spread cannot
be completely ruled out. More specifically, the maximum metallicity spread
allowed by our data is of the order of [Fe/H] dex,
i.e., not much more than what allowed by the photometric errors. Finally, we
identified most of the known variable stars and peculiar objects in our field
of view. In particular, we find additional evidence supporting previous optical
identifications of the central star of the Planetary Nebula IRAS 18333-2357,
which is associated with M~22.Comment: 15 pages, 16 figures, accepted for publication in MNRA
Zeroing the Stellar Isochrone Scale: The Red Giant Clump Luminosity at Intermediate Metallicity
The color-magnitude diagrams of the open clusters NGC 2420 and NGC 2506 have
been investigated as intermediate links between the solar neighborhood and the
Magellanic Clouds. Two sets of theoretical isochrones which include convective
overshoot are zeroed to the sun at solar abundance and to the unevolved main
sequence dwarfs of the Hipparcos catalog at [Fe/H] = -0.4, requiring a
differential of 0.4 mag between the unevolved main sequences at a given color.
Adopting E(B-V) = 0.04 and [Fe/H] = -0.39 for NGC 2506 and 0.04 and -0.29 for
NGC 2420,the respective apparent moduli are 12.70 and 12.15, while the ages of
both clusters are approximately 1.9 +/- 0.2 or 2.2 +/- 0.2 Gyr, depending on
the choice of isochrones. From the composite giant branch of the two clusters,
the mean clump magnitudes in V and I are found to be 0.47 and -0.48
(-0.17,+0.14). Applying a metallicity correction to the M_I values, the cluster
sample of Udalski (1998) leads to (m-M)_0 = 18.42 (+0.17,--0.15) and 18.91
(+0.18,--0.16) for the LMC and SMC, respectively. A caveat to this discussion
and to the claim that clusters of the same abundance and age are identical is
the observation that the (V-I) colors of the red giants in NGC 2506 are
significantly redder at a given (B-V) than the giants in clusters of comparable
age and/or metallicity. If the CCD photometry for NGC 2506 is tied to the
standard system rather than using a general cluster relation between (B-V) and
(V-I), the M_I for the clump will decrease by 0.1 mag.Comment: 1 table, 12 figures. Replaced 20-jan-99 by version with all figures.
Accepted for April 1999 Astronomical Journa
CCD uvbyHbeta Photometry in Clusters: I. The Open Cluster Standard, IC 4651
CCD photometry of the intermediate-age open cluster, IC 4651, on the
uvbyHbeta system is presented and analyzed. By using a combination of the
information from the color-magnitude diagram (CMD) and the color-color
diagrams, a sample of 98 highly probable main sequence cluster members with
high photometric accuracy is isolated. From this sample, adopting the intrinsic
color relation of Olsen (1988), E(b-y) = 0.062 +/- 0.003 and [Fe/H] = +0.077
+/- 0.012, where the errors quoted are the standard errors of the mean and
refer to the internal errors alone. Use of the Nissen (1988) intrinsic color
relation produces E(b-y) = 0.071 and [Fe/H] = +0.115. Adopting the lower
reddening, a direct main-sequence fit to the Hyades with (m-M) = 3.33 leads to
(m-M) = 10.15, while isochrones with convective overshoot and zeroed to the
Hyades produce an age of 1.7 +/- 0.1 Gyr, with an excellent match to the
morphology of the turnoff. The higher reddening produces (m-M) = 10.3 and an
age lower by 0.1 Gyr. Comparison with the CMD of NGC 3680 shows that the two
clusters have virtually identical morphology which, in combination with their
similar compositions, produces identical ages. Coincidentally, the shifts in
the CMD necessary to superpose the two clusters require that the apparent
moduli of IC 4651 and NGC 3680 be the same, while E(b-y)(4651) = E(b-y)(3680) +
0.04.Comment: 28 pages and 3 tables, in latex, 11 postscript figures. Accepted for
Astronomical Journa
Multiple populations in globular clusters. Lessons learned from the Milky Way globular clusters
Recent progress in studies of globular clusters has shown that they are not
simple stellar populations, being rather made of multiple generations. Evidence
stems both from photometry and spectroscopy. A new paradigm is then arising for
the formation of massive star clusters, which includes several episodes of star
formation. While this provides an explanation for several features of globular
clusters, including the second parameter problem, it also opens new
perspectives about the relation between globular clusters and the halo of our
Galaxy, and by extension of all populations with a high specific frequency of
globular clusters, such as, e.g., giant elliptical galaxies. We review progress
in this area, focusing on the most recent studies. Several points remain to be
properly understood, in particular those concerning the nature of the polluters
producing the abundance pattern in the clusters and the typical timescale, the
range of cluster masses where this phenomenon is active, and the relation
between globular clusters and other satellites of our Galaxy.Comment: In press (The Astronomy and Astrophysics Review
Fulvestrant plus anastrozole or placebo versus exemestane alone after progression on non-steroidal aromatase inhibitors in postmenopausal patients with hormone-receptor-positive locally advanced or metastatic breast cancer (SoFEA): a composite, multicentre, phase 3 randomised trial
SummaryBackgroundThe optimum endocrine treatment for postmenopausal women with advanced hormone-receptor-positive breast cancer that has progressed on non-steroidal aromatase inhibitors (NSAIs) is unclear. The aim of the SoFEA trial was to assess a maximum double endocrine targeting approach with the steroidal anti-oestrogen fulvestrant in combination with continued oestrogen deprivation.MethodsIn a composite, multicentre, phase 3 randomised controlled trial done in the UK and South Korea, postmenopausal women with hormone-receptor-positive breast cancer (oestrogen receptor [ER] positive, progesterone receptor [PR] positive, or both) were eligible if they had relapsed or progressed with locally advanced or metastatic disease on an NSAI (given as adjuvant for at least 12 months or as first-line treatment for at least 6 months). Additionally, patients had to have adequate organ function and a WHO performance status of 0â2. Participants were randomly assigned (1:1:1) to receive fulvestrant (500 mg intramuscular injection on day 1, followed by 250 mg doses on days 15 and 29, and then every 28 days) plus daily oral anastrozole (1 mg); fulvestrant plus anastrozole-matched placebo; or daily oral exemestane (25 mg). Randomisation was done with computer-generated permuted blocks, and stratification was by centre and previous use of an NSAI as adjuvant treatment or for locally advanced or metastatic disease. Participants and investigators were aware of assignment to fulvestrant or exemestane, but not of assignment to anastrozole or placebo. The primary endpoint was progression-free survival (PFS). Analyses were by intention to treat. This trial is registered with ClinicalTrials.gov, numbers NCT00253422 (UK) and NCT00944918 (South Korea).FindingsBetween March 26, 2004, and Aug 6, 2010, 723 patients underwent randomisation: 243 were assigned to receive fulvestrant plus anastrozole, 231 to fulvestrant plus placebo, and 249 to exemestane. Median PFS was 4·4 months (95% CI 3·4â5·4) in patients assigned to fulvestrant plus anastrozole, 4·8 months (3·6â5·5) in those assigned to fulvestrant plus placebo, and 3·4 months (3·0â4·6) in those assigned to exemestane. No difference was recorded between the patients assigned to fulvestrant plus anastrozole and fulvestrant plus placebo (hazard ratio 1·00, 95% CI 0·83â1·21; log-rank p=0·98), or between those assigned to fulvestrant plus placebo and exemestane (0·95, 0·79â1·14; log-rank p=0·56). 87 serious adverse events were reported: 36 in patients assigned to fulvestrant plus anastrozole, 22 in those assigned to fulvestrant plus placebo, and 29 in those assigned to exemestane. Grade 3â4 adverse events were rare; the most frequent were arthralgia (three in the group assigned to fulvestrant plus anastrozole; seven in that assigned to fulvestrant plus placebo; eight in that assigned to exemestane), lethargy (three; 11; 11), and nausea or vomiting (five; two; eight).InterpretationAfter loss of response to NSAIs in postmenopausal women with hormone-receptor-positive advanced breast cancer, maximum double endocrine treatment with 250 mg fulvestrant combined with oestrogen deprivation is no better than either fulvestrant alone or exemestane.FundingCancer Research UK and AstraZeneca
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