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Gender Gaps in the Measurement of Public Opinion About Homosexuality in Cross-national Surveys: A Question-Wording Experiment
Measures of attitudes towards homosexuality in cross-national studies have received criticism for not being âgender-sensitiveâ. The current study used a split-ballot design allowing for separate analyses of the attitudes towards âgay men and lesbian womenâ, âgay menâ, and âlesbian womenâ in a pooled sample of 3,381 participants from Great Britain, Hungary, and Portugal. Analyses controlling for sociodemographics showed that differences in attitudes towards male and female targets were generally small and did not interact with the gender of the rater. In addition, results showed that menâs attitudes towards homosexuality were more strongly related to their gender ideology than womenâs attitudes. Implications of these findings for cross-national studies measuring attitudes towards homosexuality are discussed
An investigation of some effects of mach number and air temperature on the hypersonic flow over a blunt body
Mach number and air temperature effect on hypersonic flow over blunt bodie
A stochastic large deformation model for computational anatomy
In the study of shapes of human organs using computational anatomy, variations are found to arise from inter-subject anatomical differences, disease-specific effects, and measurement noise. This paper introduces a stochastic model for incorporating random variations into the Large Deformation Diffeomorphic Metric Mapping (LDDMM) framework. By accounting for randomness in a particular setup which is crafted to fit the geometrical properties of LDDMM, we formulate the template estimation problem for landmarks with noise and give two methods for efficiently estimating the parameters of the noise fields from a prescribed data set. One method directly approximates the time evolution of the variance of each landmark by a finite set of differential equations, and the other is based on an Expectation-Maximisation algorithm. In the second method, the evaluation of the data likelihood is achieved without registering the landmarks, by applying bridge sampling using a stochastically perturbed version of the large deformation gradient flow algorithm. The method and the estimation algorithms are experimentally validated on synthetic examples and shape data of human corpora callosa
A Statistical Model for Simultaneous Template Estimation, Bias Correction, and Registration of 3D Brain Images
Template estimation plays a crucial role in computational anatomy since it
provides reference frames for performing statistical analysis of the underlying
anatomical population variability. While building models for template
estimation, variability in sites and image acquisition protocols need to be
accounted for. To account for such variability, we propose a generative
template estimation model that makes simultaneous inference of both bias fields
in individual images, deformations for image registration, and variance
hyperparameters. In contrast, existing maximum a posterori based methods need
to rely on either bias-invariant similarity measures or robust image
normalization. Results on synthetic and real brain MRI images demonstrate the
capability of the model to capture heterogeneity in intensities and provide a
reliable template estimation from registration
Some measurements of the dynamic and static stability of two blunt-nosed, low-fineness- ratio bodies of revolution in free flight at mequal4
Dynamic and static stability of two blunt nosed low fineness ratio bodies of revolution in free flight - ballistic
A dynamical and kinematical model of the Galactic stellar halo and possible implications for galaxy formation scenarios
We re-analyse the kinematics of the system of blue horizontal branch field
(BHBF) stars in the Galactic halo (in particular the outer halo), fitting the
kinematics with the model of radial and tangential velocity dispersions in the
halo as a function of galactocentric distance r proposed by Sommer-Larsen,
Flynn & Christensen (1994), using a much larger sample (almost 700) of BHBF
stars. The basic result is that the character of the stellar halo velocity
ellipsoid changes markedly from radial anisotropy at the sun to tangential
anisotropy in the outer parts of the Galactic halo (r greater than approx 20
kpc). Specifically, the radial component of the stellar halo's velocity
ellipsoid decreases fairly rapidly beyond the solar circle, from approx 140 +/-
10 km/s at the sun, to an asymptotic value of 89 +/- 19 km/s at large r. The
rapid decrease in the radial velocity dispersion is matched by an increase in
the tangential velocity dispersion, with increasing r.
Our results may indicate that the Galaxy formed hierarchically (partly or
fully) through merging of smaller subsystems - the 'bottom-up' galaxy formation
scenario, which for quite a while has been favoured by most theorists and
recently also has been given some observational credibility by HST observations
of a potential group of small galaxies, at high redshift, possibly in the
process of merging to a larger galaxy (Pascarelle et al 1996).Comment: Latex, 16 pages. 2 postscript figures. Submitted to the Astrophysical
Journal. also available at http://astro.utu.fi/~cflynn/outerhalo.htm
Investigation of scaling properties of hysteresis in Finemet thin films
We study the behavior of hysteresis loops in Finemet
FeCuNbSiB thin films by using a fluxometric setup
based on a couple of well compensated pickup coils. The presence of scaling
laws of the hysteresis area is investigated as a function of the amplitude and
frequency of the applied field, considering sample thickness from about 20 nm
to 5 m. We do not observe any scaling predicted by theoretical models,
while dynamic loops show a logarithmic dependence on the frequency.Comment: 2 pages, 2 figure
X-ray Emission from Haloes of Simulated Disc Galaxies
Bolometric and 0.2-2 keV X-ray luminosities of the hot gas haloes of
simulated disc galaxies have been calculated at redshift z=0. The TreeSPH
simulations are fully cosmological and the sample of 44 disc galaxies span a
range in characteristic circular speeds of V_c = 130-325 km/s. The galaxies
have been obtained in simulations with a considerable range of physical
parameters, varying the baryonic fraction, the gas metallicity, the
meta-galactic UV field, the cosmology, the dark matter type, and also the
numerical resolution. The models are found to be in agreement with the (few)
relevant X-ray observations available at present. The amount of hot gas in the
haloes is also consistent with constraints from pulsar dispersion measures in
the Milky Way. Forthcoming XMM and Chandra observations should enable much more
stringent tests and provide constraints on the physical parameters. We find
that simple cooling flow models over-predict X-ray luminosities by up to two
orders of magnitude for high (but still realistic) cooling efficiencies
relative to the models presented here. Our results display a clear trend that
increasing cooling efficiency leads to decreasing X-ray luminosities at z=0.
The reason is found to be that increased cooling efficiency leads to a
decreased fraction of hot gas relative to total baryonic mass inside of the
virial radius at present. At gas metal abundances of a third solar this hot gas
fraction becomes as low as just a few percent. We also find that most of the
X-ray emission comes from the inner parts (inner about 20 kpc) of the hot
galactic haloes. Finally, we find for realistic choices of the physical
parameters that disc galaxy haloes possibly were more than one order of
magnitude brighter in soft X-ray emission at z=1, than at present.Comment: 8 pages, 7 figures, MNRAS LaTeX forma
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