9,889 research outputs found
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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 ‘gender-sensitive’. The current study used a split-ballot design allowing for separate analyses of the attitudes towards ‘gay men and lesbian women’, ‘gay men’, and ‘lesbian women’ 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 men’s attitudes towards homosexuality were more strongly related to their gender ideology than women’s attitudes. Implications of these findings for cross-national studies measuring attitudes towards homosexuality are discussed
Laser microprobe study of cosmic dust (IDPs) and potential source materials
The study of cosmic dust or interplanetary dust particles (IDP) can provide vital information about primitive materials derived primarily from comets and asteroids along with a small unknown fraction from the nearby interstellar medium. The study of these particles can enhance our understanding of comets along with the decoding of the history of the early solar system. In addition the study of the cosmic dust for IDP particles can assist in the elucidation of the cosmic history of the organogenic elements which are vital to life processes. Studies to date on these particles have shown that they are complex, heterogeneous assemblages of both amorphous and crystalline components. In order to understand the nature of these particles, any analytical measurements must be able to distinguish between the possible sources of these particles. A study was undertaken using a laser microprobe interfaced to a quadrupole mass spectrometer for the analysis of the volatile components present in cosmic dust particles, terrestrial contaminants present in the upper atmosphere, and primitive carbonaceous chondrites. From the study of the volatiles released from the carbonaceous materials it is hoped that one could distinguish between components and sources in the IDP particles analyzed. The technique is briefly described and results for the CI, CM, and CV chondrites and cosmic dust particle W7027B8 are presented
Geochemical and spectral characterization of naturally altered rock surfaces
The possibility of using the visible-near infrared region for compositional analysis of remotely sensed rock surfaces is studied. This would allow mapping rock type both on the Earth's surface and on other planetary surfaces. Reflectance spectroscopy, economic geology, optical depth determination, and X-ray diffraction mineralogy are discussed
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How do you search for the best alternative? Experimental evidence on search strategies to solve complex problems
Through a controlled two-stage experiment, we explore the performance of solution search strategies to resolve problems of varying complexity. We validate theoretical results that collaborative group structures may search more effectively in problems of low complexity, but are outperformed by nominal structures at higher complexity levels. We call into question the dominance of the nominal group
technique. Further close examination of search strategies reveals important insights: the number of generated solutions, a typical proxy for good problem-solving performance, does not consistently drive performance benefits across different levels of problem complexity. The average distance of search steps, and the problem space coverage play also critical roles. Moreover, their effect is contingent on complexity:a wider variety of solutions is helpful only in complex problems. Overall, we caution management about the limitations of generic, albeit common rules-of-thumb such as "generate as many ideas as possible”
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
Ongoing Galactic Accretion: Simulations and Observations of Condensed Gas in Hot Halos
Ongoing accretion onto galactic disks has been recently theorized to progress
via the unstable cooling of the baryonic halo into condensed clouds. These
clouds have been identified as analogous to the High-Velocity Clouds (HVCs)
observed in HI in our Galaxy. Here we compare the distribution of HVCs observed
around our own Galaxy and extra-planar gas around the Andromeda galaxy to these
possible HVC analogs in a simulation of galaxy formation that naturally
generates these condensed clouds. We find a very good correspondence between
these observations and the simulation, in terms of number, angular size,
velocity distribution, overall flux and flux distribution of the clouds. We
show that condensed cloud accretion only accounts for ~ 0.2 M_solar / year of
the current overall Galactic accretion in the simulations. We also find that
the simulated halo clouds accelerate and become more massive as they fall
toward the disk. The parameter space of the simulated clouds is consistent with
all of the observed HVC complexes that have distance constraints, except the
Magellanic Stream which is known to have a different origin. We also find that
nearly half of these simulated halo clouds would be indistinguishable from
lower-velocity gas and that this effect is strongest further from the disk of
the galaxy, thus indicating a possible missing population of HVCs. These
results indicate that the majority of HVCs are consistent with being infalling,
condensed clouds that are a remnant of Galaxy formation.Comment: 10 pages, 6 figures, ApJ Accepted. Some changes to techniqu
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