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The economics of health
This report presents results from the Economics of Health project funded by the East Midlands Development Agency. The work was undertaken between November 2007 and February 2008. The main aim of the project was to examine the relationship between mental and physical health and employability, labour market participation and economic performance, with specific attention given to the direction of causal relationships
Partnership Instability and Child Wellbeing during the Transition to Elementary School
Data from the Fragile Families and Child Wellbeing Study (N = 2,957) are used to examine partnership instability and childrenâs wellbeing during the transition to elementary school. We find that coresidential transitions are related to externalizing, attention, and social problems. Mothersâ mental health and use of harsh parenting partially mediate the associations between coresidential transitions and child outcomes at age five. The impact of coresidential transitions on externalizing, attention, and social problems is stronger for boys than girls. Also, non-coresidential transitions predict externalizing and attention problems for White children but not for Hispanic children. Finally, the association between coresidential transitions and verbal ability is stronger for children with highly educated mothers than for children of less educated mothers.
Algebras for parameterised monads
Parameterised monads have the same relationship to adjunctions with parameters as monads do to adjunctions. In this paper, we investigate algebras for parameterised monads. We identify the Eilenberg-Moore category of algebras for parameterised monads and prove a generalisation of Beckâs theorem characterising this category. We demonstrate an application of this theory to the semantics of type and effect systems
Money in monetary policy design: monetary cross-checking in the New-Keynesian model
In the New-Keynesian model, optimal interest rate policy under uncertainty is formulated without reference to monetary aggregates as long as certain standard assumptions on the distributions of unobservables are satisfied. The model has been criticized for failing to explain common trends in money growth and inflation, and that therefore money should be used as a cross-check in policy formulation (see Lucas (2007)). We show that the New-Keynesian model can explain such trends if one allows for the possibility of persistent central bank misperceptions. Such misperceptions motivate the search for policies that include additional robustness checks. In earlier work, we proposed an interest rate rule that is near-optimal in normal times but includes a cross-check with monetary information. In case of unusual monetary trends, interest rates are adjusted. In this paper, we show in detail how to derive the appropriate magnitude of the interest rate adjustment following a significant cross-check with monetary information, when the New-Keynesian model is the central bankâs preferred model. The cross-check is shown to be effective in offsetting persistent deviations of inflation due to central bank misperceptions. Keywords: Monetary Policy, New-Keynesian Model, Money, Quantity Theory, European Central Bank, Policy Under Uncertaint
PO and PN in the wind of the oxygen-rich AGB star IK Tau
Phosphorus-bearing compounds have only been studied in the circumstellar
environments (CSEs) of the asymptotic giant branch (AGB) star IRC +10216 and
the protoplanetary nebula CRL 2688, both C-rich objects, and the O-rich red
supergiant VY CMa. The current chemical models cannot reproduce the high
abundances of PO and PN derived from observations of VY CMa. No observations
have been reported of phosphorus in the CSEs of O-rich AGB stars. We aim to set
observational constraints on the phosphorous chemistry in the CSEs of O-rich
AGB stars, by focussing on the Mira-type variable star IK Tau. Using the IRAM
30m telescope and the Submillimeter Array (SMA), we observed four rotational
transitions of PN (J=2-1,3-2,6-5,7-6) and four of PO
(J=5/2-3/2,7/2-5/2,13/2-11/2,15/2-13/2). The IRAM 30m observations were
dedicated line observations, while the SMA data come from an unbiased spectral
survey in the frequency range 279-355 GHz.
We present the first detections of PN and PO in an O-rich AGB star and
estimate abundances X(PN/H2) of about 3x10^-7 and X(PO/H2) in the range
0.5-6.0x10^-7. This is several orders of magnitude higher than what is found
for the C-rich AGB star IRC +10216. The diameter (<=0.7") of the PN and PO
emission distributions measured in the interferometric data corresponds to a
maximum radial extent of about 40 stellar radii. The abundances and the spatial
occurrence of the molecules are in very good agreement with the results
reported for VY CMa. We did not detect PS or PH3 in the survey. We suggest that
PN and PO are the main carriers of phosphorus in the gas phase, with abundances
possibly up to several 10^-7. The current chemical models cannot account for
this, underlining the strong need for updated chemical models that include
phosphorous compounds.Comment: Accepted for publication in Astronomy & Astrophysics, 10 pages, 8
figure
Lattice Point Generating Functions and Symmetric Cones
We show that a recent identity of Beck-Gessel-Lee-Savage on the generating
function of symmetrically contrained compositions of integers generalizes
naturally to a family of convex polyhedral cones that are invariant under the
action of a finite reflection group. We obtain general expressions for the
multivariate generating functions of such cones, and work out the specific
cases of a symmetry group of type A (previously known) and types B and D (new).
We obtain several applications of the special cases in type B, including
identities involving permutation statistics and lecture hall partitions.Comment: 19 page
The social, cosmopolitanism and beyond
First, this article will outline the metaphysics of âthe socialâ that implicitly and explicitly connects the work of lassical and contemporary cosmopolitan sociologists as different as Durkheim, Weber, Beck and Luhmann. In a second step, I will show that the cosmopolitan outlook of classical sociology is driven by exclusive differences. In understanding human affairs, both classical sociology and contemporary cosmopolitan sociology reflect a very modernist outlook of epistemological, conceptual, methodological and disciplinary rigour that separates the cultural sphere from the natural objects of concern. I will suggest that classical sociology â in order to be cosmopolitan â is forced (1) to exclude non-social and non-human objects as part of its conceptual and methodological rigour, and (2) consequently and methodologically to rule out the non-social and the non-human. Cosmopolitan sociology imagines âthe socialâ as a global, universal explanatory device to conceive and describe the non-social and non-human. In a third and final step the article draws upon the work of the French sociologist Gabriel Tarde and offers a possible alternative to the modernist social and cultural other-logics of social sciences. It argues for a inclusive conception of âthe socialâ that gives the non-social and non-human a cosmopolitan voice as well
Synchrotron Radiation From Radiatively Inefficient Accretion Flow Simulations: Applications to Sgr A*
We calculate synchrotron radiation in three-dimensional pseudo-Newtonian
magnetohydrodynamic simulations of radiatively inefficient accretion flows. We
show that the emission is highly variable at optically thin frequencies, with
order of magnitude variability on time-scales as short as the orbital period
near the last stable orbit; this emission is linearly polarized at the 20-50 %
level due to the coherent toroidal magnetic field in the flow. At optically
thick frequencies, both the variability amplitude and polarization fraction
decrease significantly with decreasing photon frequency. We argue that these
results are broadly consistent with the observed properties of Sgr A* at the
Galactic Center, including the rapid infrared flaring.Comment: Accepted for publication in Ap
Search for aluminium monoxide in the winds of oxygen-rich AGB stars
Aluminium monoxide, AlO, is likely efficiently depleted from the gas around
oxygen-rich evolved stars to form alumina clusters and dust seeds. Its presence
in the extended atmospheres of evolved stars has been derived from optical
spectroscopy. More recently, AlO gas was also detected at long wavelengths
around the supergiant VY CMa and the oxygen-rich asymptotic giant branch (AGB)
star o Cet (Mira A). In search of AlO, we mined data obtained with APEX, the
IRAM 30m telescope, Herschel/HIFI, SMA, and ALMA, which were primarily aimed at
studying other molecular species. We report here on observations of AlO towards
a sample of eight oxygen-rich AGB stars in different rotational transitions, up
to seven for some stars. We present definite detections of one rotational
transition of AlO for o Cet and R Aqr, and tentative detections of one
transition for R Dor and o Cet, and two for IK Tau and W Hya. The presented
spectra of WX Psc, R Cas, and TX Cam show no signature of AlO. For o Cet, R
Aqr, and IK Tau, we find that the AlO(N=9-8) emission likely traces the inner
parts of the wind, out to only a few tens of AU, where the gas has not yet
reached its terminal velocity. The conclusive detections of AlO emission in the
case of o Cet and R Aqr confirm the presence of AlO gas in outflows of AGB
stars. The tentative detections further support this. Since most of the
observations presented in this study were obtained with stronger emission from
other species than AlO in mind, observations with higher sensitivity in
combination with high angular resolution will improve our understanding of the
presence and behaviour of AlO. From the current data sets we cannot firmly
conclude whether there is a direct correlation between the wind properties and
the detection rate of AlO emission. We hope that this study can serve as a
stimulus to perform sample studies in search of AlO in oxygen-rich outflows.Comment: 9 pages, 9 figures, Accepted for publication in Astronomy &
Astrophysic
Experimental Lagrangian Acceleration Probability Density Function Measurement
We report experimental results on the acceleration component probability
distribution function at to probabilities of less than
. This is an improvement of more than an order of magnitude over past
measurements and allows us to conclude that the fourth moment converges and the
flatness is approximately 55. We compare our probability distribution to those
predicted by several models inspired by non-extensive statistical mechanics. We
also look at acceleration component probability distributions conditioned on a
velocity component for conditioning velocities as high as 3 times the standard
deviation and find them to be highly non-Gaussian.Comment: submitted for the special issue of Physica D: "Anomalous
Distributions" 11 pages, 6 figures revised version: light modifications of
the figures and the tex
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