295 research outputs found
Gender Differences Associated With Memory Recall
This study investigated whether a gender difference existed in the context of romantic relationships. Participants rated positively valanced words and negatively valanced words, that were related to a romantic relationship, on how relevant they were to realistic romantic relationships. Participants were then given a free recall task to recall any words that they rated earlier. The study found that a gender difference did exist in the context of negatively valanced words. Women were more successful in recall of negatively valanced words than men. These findings indicate that women encode emotional information differently than men encode emotional information and recall that information more easily than male participants
Gravitational Nanolensing from Subsolar Mass Dark Matter Halos
We investigate the feasibility of extracting the gravitational nanolensing
signal due to the presence of subsolar mass halos within galaxy-sized dark
matter halos. We show that subsolar mass halos in a lensing galaxy can cause
strong nanolensing events with shorter durations and smaller amplitudes than
microlensing events caused by stars. We develop techniques that can be used in
future surveys such as Pan-STARRS, LSST and OMEGA to search for the nanolensing
signal from subsolar mass halos.Comment: 12 pages, 10 figures. Replaced with version accepted for publication
in ApJ. Very minor changes from version
The Metallicity Distribution Functions of SEGUE G and K dwarfs: Constraints for Disk Chemical Evolution and Formation
We present the metallicity distribution function (MDF) for 24,270 G and
16,847 K dwarfs at distances from 0.2 to 2.3 kpc from the Galactic plane, based
on spectroscopy from the Sloan Extension for Galactic Understanding and
Exploration (SEGUE) survey. This stellar sample is significantly larger in both
number and volume than previous spectroscopic analyses, which were limited to
the solar vicinity, making it ideal for comparison with local volume-limited
samples and Galactic models. For the first time, we have corrected the MDF for
the various observational biases introduced by the SEGUE target selection
strategy. The SEGUE sample is particularly notable for K dwarfs, which are too
faint to examine spectroscopically far from the solar neighborhood. The MDF of
both spectral types becomes more metal-poor with increasing |Z|, which reflects
the transition from a sample with small [alpha/Fe] values at small heights to
one with enhanced [alpha/Fe] above 1 kpc. Comparison of our SEGUE distributions
to those of two different Milky Way models reveals that both are more
metal-rich than our observed distributions at all heights above the plane. Our
unbiased observations of G and K dwarfs provide valuable constraints over the
|Z|-height range of the Milky Way disk for chemical and dynamical Galaxy
evolution models, previously only calibrated to the solar neighborhood, with
particular utility for thin- and thick-disk formation models.Comment: 70 pages, 25 figures, 7 tables. Accepted by The Astrophysical Journa
Light Curve Templates and Galactic Distribution of RR Lyrae Stars from Sloan Digital Sky Survey Stripe 82
We present an improved analysis of halo substructure traced by RR Lyrae stars
in the SDSS stripe 82 region. With the addition of SDSS-II data, a revised
selection method based on new ugriz light curve templates results in a sample
of 483 RR Lyrae stars that is essentially free of contamination. The main
result from our first study persists: the spatial distribution of halo stars at
galactocentric distances 5--100 kpc is highly inhomogeneous. At least 20% of
halo stars within 30 kpc from the Galactic center can be statistically
associated with substructure. We present strong direct evidence, based on both
RR Lyrae stars and main sequence stars, that the halo stellar number density
profile significantly steepens beyond a Galactocentric distance of ~30 kpc, and
a larger fraction of the stars are associated with substructure. By using a
novel method that simultaneously combines data for RR Lyrae and main sequence
stars, and using photometric metallicity estimates for main sequence stars
derived from deep co-added u-band data, we measure the metallicity of the
Sagittarius dSph tidal stream (trailing arm) towards R.A.2h-3h and Dec~0 deg to
be 0.3 dex higher ([Fe/H]=-1.2) than that of surrounding halo field stars.
Together with a similar result for another major halo substructure, the
Monoceros stream, these results support theoretical predictions that an early
forming, smooth inner halo, is metal poor compared to high surface brightness
material that have been accreted onto a later-forming outer halo. The mean
metallicity of stars in the outer halo that are not associated with detectable
clumps may still be more metal-poor than the bulk of inner-halo stars, as has
been argued from other data sets.Comment: Submitted to ApJ, 68 pages, 26 figures, supplemental material (light
curves, templates, animation) can be downloaded from
http://www.astro.washington.edu/bsesar/S82_RRLyr.htm
The assertive cardiac care trial: A randomised controlled trial of a coproduced assertive cardiac care intervention to reduce absolute cardiovascular disease risk in people with severe mental illness in the primary care setting
BACKGROUND: Cardiovascular disease (CVD) accounts for 40% of the excess mortality identified in people with severe mental illness (SMI). Modifiable CVD risk factors are higher and can be exacerbated by the cardiometabolic impact of psychotropic medications. People with SMI frequently attend primary care presenting a valuable opportunity for early identification, prevention and management of cardiovascular health. The ACCT Healthy Hearts Study will test a coproduced, nurse-led intervention delivered with general practitioners to reduce absolute CVD risk (ACVDR) at 12 months compared with an active control group. METHODS/DESIGN: ACCT is a two group (intervention/active control) individually randomised (1:1) controlled trial (RCT). Assessments will be completed baseline (pre-randomisation), 6 months, and 12 months. The primary outcome is 5-year ACVDR measured at 12 months. Secondary outcomes include 6-month ACVDR; and blood pressure, lipids, HbA1c, BMI, quality of life, physical activity, motivation to change health behaviour, medication adherence, alcohol use and hospitalisation at 6 and 12 months. Linear mixed-effects regression will estimate mean difference between groups for primary and secondary continuous outcomes. Economic cost-consequences analysis will be conducted using quality of life and health resource use information and routinely collected government health service use and medication data. A parallel process evaluation will investigate implementation of the intervention, uptake and outcomes. DISCUSSION: ACCT will deliver a coproduced and person-centred, guideline level cardiovascular primary care intervention to a high need population with SMI. If successful, the intervention could lead to the reduction of the mortality gap and increase opportunities for meaningful social and economic participation. Trial registration ANZCTR Trial number: ACTRN12619001112156
The Different Physical Mechanisms that Drive the Star-Formation Histories of Giant and Dwarf Galaxies
We present an analysis of star-formation and nuclear activity in galaxies as
a function of both luminosity and environment in the SDSS DR4 dataset. Using a
sample of 27753 galaxies at 0.00590% complete to Mr=-18.0 we
find that the EW(Ha) distribution is strongly bimodal, allowing galaxies to be
robustly separated into passive and star-forming populations about a value
EW(Ha)=2A. In high-density regions ~70% of galaxies are passive independent of
luminosity. In the rarefied field however, the fraction of passively-evolving
galaxies is a strong function of luminosity, dropping from ~50% for Mr<-21 to
zero by Mr~-18. Indeed for the lowest luminosity range covered (-18<Mr<-16)
none of the ~600 galaxies in the lowest density quartile are passive. The few
passively-evolving dwarf galaxies in field regions appear as satellites to
bright (~L*) galaxies. The fraction of galaxies with optical AGN signatures
decreases steadily from ~50% at Mr~-21 to ~0% by Mr~-18 closely mirroring the
luminosity-dependence of the passive galaxy fraction in low-density
environments. This result reflects the increasing importance of AGN feedback
with galaxy mass for their evolution, such that the star-formation histories of
massive galaxies are primarily determined by their past merger history. In
contrast, the complete absence of passively-evolving dwarf galaxies more than
~2 virial radii from the nearest massive halo (i.e. cluster, group or massive
galaxy) indicates that internal processes, such as merging, AGN feedback or gas
consumption through star-formation, are not responsible for terminating
star-formation in dwarf galaxies. Instead the evolution of dwarf galaxies is
primarily driven by the mass of their host halo, probably through the combined
effects of tidal forces and ram-pressure stripping.Comment: 29 pages, 11 figures. Accepted for publication in MNRA
The assertive cardiac care trial: a randomised controlled trial of a coproduced assertive cardiac care intervention to reduce absolute cardiovascular disease risk in people with severe mental illness in the primary care setting
Background: Cardiovascular disease (CVD) accounts for 40% of the excess mortality identified in people with severe mental illness (SMI). Modifiable CVD risk factors are higher and can be exacerbated by the cardiometabolic impact of psychotropic medications. People with SMI frequently attend primary care presenting a valuable opportunity for early identification, prevention and management of cardiovascular health. The ACCT Healthy Hearts Study will test a coproduced, nurse-led intervention delivered with general practitioners to reduce absolute CVD risk (ACVDR) at 12 months compared with an active control group. Methods/design: ACCT is a two group (intervention/active control) individually randomised (1:1) controlled trial (RCT). Assessments will be completed baseline (pre-randomisation), 6 months, and 12 months. The primary outcome is 5-year ACVDR measured at 12 months. Secondary outcomes include 6-month ACVDR; and blood pressure, lipids, HbA1c, BMI, quality of life, physical activity, motivation to change health behaviour, medication adherence, alcohol use and hospitalisation at 6 and 12 months. Linear mixed-effects regression will estimate mean difference between groups for primary and secondary continuous outcomes. Economic cost-consequences analysis will be conducted using quality of life and health resource use information and routinely collected government health service use and medication data. A parallel process evaluation will investigate implementation of the intervention, uptake and outcomes. Discussion: ACCT will deliver a coproduced and person-centred, guideline level cardiovascular primary care intervention to a high need population with SMI. If successful, the intervention could lead to the reduction of the mortality gap and increase opportunities for meaningful social and economic participation
Seroepidemiology of Bovine Viral Diarrhoea Virus (BVDV) in the Adamawa Region of Cameroon and Use of the SPOT Test to Identify Herds with PI Calves
Bovine viral diarrhoea, caused by the bovine viral diarrhoea virus (BVDV) in the Pestivirus genus of the Flaviviridae, is one of the most important diseases of cattle world wide causing poor reproductive performance in adult cattle and mucosal disease in calves. In addition it causes immunosuppression and increased susceptibility to other infections, the impact of which is uncertain, particularly in sub-Saharan Africa where animals are exposed to a much wider range and higher intensity of infections compared to Europe. There are no previous estimates of the seroprevalence of BVDV in cattle in Cameroon. This paper describes the serological screening for antibodies to BVDV and antigen of BVDV in a cattle population in the Adamawa Region of Cameroon in 2000. The estimates of herd-level and within herd seroprevalences adjusted for test imperfections were 92% and 30% respectively and 16.5% of herds were classed as having a persistently infected calf (PI) in the herd within the last year based on the “spot” test approach. There was evidence of clustering of herds with PI calves across the north and west of the Region which corresponds with the higher cattle density areas and of self-clearance of infection from herds. A multivariable model was developed for the risk of having a PI calf in the herd; proximity to antelope, owning a goat, mixing with 10 other herds at grazing and the catchment area of the veterinary centre the herd was registered at were all significant risk factors. Very little is known about BVDV in sub-Saharan Africa and these high seroprevalences suggest that there is a large problem which may be having both direct impacts on fertility and neonate mortality and morbidity and also indirect effects through immunosuppression and susceptibility to other infections. Understanding and accounting for BVDV should be an important component of epidemiological studies of other diseases in sub-Saharan Africa
The causal effects of survivors’ benefits on health status and poverty of widows in Turkey: Evidence from Bayesian Networks
© 2016 Economic Society of Australia, Queensland. This study examines the effects of survivor benefits on health status and wealth in households of widowed mothers. The analysis relies on the cross-sectional Income and Living Conditions Survey (ILCS) in Turkey over the period 2006–2012. We apply Ordered Logit and Probit models, and we propose the Bayesian Network (BN) framework to explore the causal effects of survivor benefits using observational data. The results show that the widowed mothers who receive the benefits are more likely to report higher levels of health status by 0.11 units on a scale between 1–5. In addition, their wealth is improved. For the sample of the survivor benefit claimants, the effects of the benefits are positive, and they improve health status by about 6 per cent
Measuring the predictability of life outcomes with a scientific mass collaboration.
How predictable are life trajectories? We investigated this question with a scientific mass collaboration using the common task method; 160 teams built predictive models for six life outcomes using data from the Fragile Families and Child Wellbeing Study, a high-quality birth cohort study. Despite using a rich dataset and applying machine-learning methods optimized for prediction, the best predictions were not very accurate and were only slightly better than those from a simple benchmark model. Within each outcome, prediction error was strongly associated with the family being predicted and weakly associated with the technique used to generate the prediction. Overall, these results suggest practical limits to the predictability of life outcomes in some settings and illustrate the value of mass collaborations in the social sciences
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