8,840 research outputs found
Patients' preferences for the management of non-metastatic prostate cancer: discrete choice experiment
Objective To establish which attributes of conservative treatments for prostate cancer are most important to men. Design Discrete choice experiment. Setting Two London hospitals. Participants 129 men with non-metastatic prostate cancer, mean age 70 years; 69 of 118 (58%) with T stage 1 or 2 cancer at diagnosis. Main outcome measures Men's preferences for, and trade-offs between, the attributes of diarrhoea, hot flushes, ability to maintain an erection, breast swelling or tenderness, physical energy, sex drive, life expectancy, and out of pocket expenses. Results The men's responses to changes in attributes were all statistically significant. When asked to assume a starting life expectancy of five years, the men were willing to make trade-offs between life expectancy and side effects. On average, they were most willing to give up life expectancy to avoid limitations in physical energy (mean three months) and least willing to trade life expectancy to avoid hot flushes (mean 0.6 months to move from a moderate to mild level or from mild to none). Conclusions Men with prostate cancer are willing to participate in a relatively complex exercise that weighs up the advantages and disadvantages of various conservative treatments for their condition. They were willing to trade off some life expectancy to be relieved of the burden of troublesome side effects such as limitations in physical energy
Scaling Laws in Hierarchical Clustering Models with Poisson Superposition
Properties of cumulant- and combinant ratios are studied for multihadron
final states composed of Poisson distributed clusters. The application of these
quantities to ``detect'' clusters is discussed. For the scaling laws which hold
in hierarchical clustering models (void scaling, combinant scaling) a
generalization is provided. It is shown that testing hierarchical models is
meaningful only for phase-space volumes not larger than the characteristic
correlation length introduced by Poisson superposition. Violation of the
scaling laws due to QCD effects is predicted.Comment: 14 pages, Plain TeX, no figure
A critical appraisal of McKinnon's complementarity hypothesis: Does the real rate of return on money matter for investment in developing countries?
This is the post-print version of the final paper published in World Development. The
published article is available from the link below.
Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting,
and other quality control mechanisms may not be reflected in this document. Changes may have been made to
this work since it was submitted for publication. Copyright @ 2009 Elsevier B.V.McKinnon’s [McKinnon, R. I. (1973). Moneyandcapitalineconomicdevelopment. Washington, DC: The Brookings Institution] complementarity hypothesis predicts that money and investment are complementary due to self-financed investment, so that a real deposit rate is the key determinant of capital formation for developing economies. This paper critically appraises this contention by conducting a vigorous empirical approach using panel data for 107 developing countries. The long-run and dynamic estimation results based on McKinnon’s theoretical model are supportive of the hypothesis. However, when the investment model is conditioned by factors such as financial development, different income levels across developing countries, external inflows, public finance, and trade constraints, the credibility of the hypothesis is undermined
Origin of Radially Increasing Stellar Scaleheight in a Galactic Disk
For the past twenty years, it has been accepted that the vertical scaleheight
of the stellar disk in spiral galaxies is constant with radius. However, there
is no clear physical explanation for this in the literature. Here we calculate
the vertical stellar scaleheight for a self-gravitating stellar disk including
the additional gravitational force of the HI and H_2 gas and the dark matter
halo. We apply our model to two edge-on galaxies, NGC 891 and NGC 4565, and
find that the resulting scaleheight shows a linear increase of nearly a factor
of two within the optical disk for both these galaxies. Interestingly, we show
that the observed data when looked at closely, do not imply a constant
scaleheight but actually support this moderate flaring in scaleheight.Comment: 8 pages, 4 .EPS figures, Astron. & Astrophys Letters, In press (Vol
390, L35 - L38
A new approach to gravitational clustering: a path-integral formalism and large-N expansions
We show that the formation of large-scale structures through gravitational
instability in the expanding universe can be fully described through a
path-integral formalism. We derive the action S[f] which gives the statistical
weight associated with any phase-space distribution function f(x,p,t). This
action S describes both the average over the Gaussian initial conditions and
the Vlasov-Poisson dynamics. Next, applying a standard method borrowed from
field theory we generalize our problem to an N-field system and we look for an
expansion over powers of 1/N. We describe three such methods and we derive the
corresponding equations of motion at the lowest non-trivial order for the case
of gravitational clustering. This yields a set of non-linear equations for the
mean \fb and the two-point correlation G of the phase-space distribution f,
as well as for the response function R. These systematic schemes match the
usual perturbative expansion on quasi-linear scales but should also be able to
handle the non-linear regime. Our approach can also be extended to non-Gaussian
initial conditions and may serve as a basis for other tools borrowed from field
theory.Comment: 22 pages, final version published in A&
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