6,229 research outputs found
Protective Behavioral Strategies Underutilization Mediates Effect of a Brief Motivational Intervention among Socially Anxious Undergraduate Drinkers
Social anxiety (SA) is implicated in problematic undergraduate drinking. Brief motivational interventions (BMIs) reduce problematic undergraduate drinking. However, not all students benefit. Identification of vulnerable subgroups is an important next step. The current study examined the role of SA and protective behavioral strategies (PBS) on BMI outcomes. We reanalyzed a subset of data (53.3%; N = 120; 62.5% male) from a randomized trial in which heavy drinking undergraduates were randomized to a BMI or control. SA, past-month typical drinks, peak drinks, weekly quantity, alcohol problems, and PBS were assessed at baseline and 6-weeks. Main effects and interaction among the intervention condition (BMI vs. control) and SA group (low vs. high) were tested on alcohol outcomes and PBS. High SA undergraduates reported greater baseline drinking, more alcohol problems, and lower PBS. Post-BMI, high SA drinkers continued to report greater peak drinks, typical drinks, alcohol problems, and lower PBS use, controlling for baseline use. Among the BMI condition, parallel multiple mediation analyses revealed the PBS subscale Manner of Drinking uniquely mediated the relationship between SA and heavier post-BMI drinking. The PBS Manner of Drinking and Serious Harm Reduction subscales jointly mediated the relationship between SA and greater post-BMI alcohol problems. BMIs may need to be refined to improve outcomes for socially anxious drinkers. Increasing PBS utilization post-BMI may help improve BMI efficacy in this vulnerable group. Clinical implications are discussed
Duality Invariance of Cosmological Perturbation Spectra
I show that cosmological perturbation spectra produced from quantum
fluctuations in massless or self-interacting scalar fields during an
inflationary era remain invariant under a two parameter family of
transformations of the homogeneous background fields. This relates slow-roll
inflation models to solutions which may be far from the usual slow-roll limit.
For example, a scale-invariant spectrum of perturbations in a minimally
coupled, massless field can be produced by an exponential expansion with
, or by a collapsing universe with .Comment: 5 pages, Latex with Revtex. Hamiltonian formulation added and
discussion expanded. Version to appear in Phys Rev
Cayratia clematidea (F.Muell.) Domin
https://thekeep.eiu.edu/herbarium_specimens_byname/19435/thumbnail.jp
Cosmological perturbation spectra from SL(4,R)-invariant effective actions
We investigate four-dimensional cosmological vacuum solutions derived from an
effective action invariant under global SL(n,R) transformations. We find the
general solutions for linear axion field perturbations about homogeneous
dilaton-moduli-vacuum solutions for an SL(4,R)-invariant action and find the
spectrum of super-horizon perturbations resulting from vacuum fluctuations in a
pre big bang scenario. We show that for SL(n,R)-invariant actions with n>3
there exists a regime of parameter space of non-zero measure where all the
axion field spectra have positive spectral tilt, as required if light axion
fields are to provide a seed for anisotropies in the microwave background and
large-scale structure in the universe.Comment: 8 pages, 3 figures, revtex plus epsf, minor typos corrected, version
to appear in Physical Review
Some stationary properties of a -ball in arbitrary space dimensions
Introducing new physically motivated ans\"{a}tze, we explore both
analytically and numerically the classical and absolute stabilities of a single
-ball in an arbitrary number of spatial dimensions , working in both the
thin and thick wall limits.Comment: 35 pages, 32 figures; added references, corrected typo
On the reliability of inflaton potential reconstruction
If primordial scalar and tensor perturbation spectra can be inferred from
observations of the cosmic background radiation and large-scale structure, then
one might hope to reconstruct a unique single-field inflaton potential capable
of generating the observed spectra. In this paper we examine conditions under
which such a potential can be reliably reconstructed. For it to be possible at
all, the spectra must be well fit by a Taylor series expansion. A complete
reconstruction requires a statistically-significant tensor mode to be measured
in the microwave background. We find that the observational uncertainties
dominate the theoretical error from use of the slow-roll approximation, and
conclude that the reconstruction procedure will never insidiously lead to an
irrelevant potential.Comment: 16 page LaTeX file with eight postscript figures embedded with epsf;
no special macros neede
Dependence of Inflationary Reconstruction upon Cosmological Parameters
The inflationary potential and its derivatives determine the spectrum of
scalar and tensor metric perturbations that arise from quantum fluctuations
during inflation. The CBR anisotropy offers a promising means of determining
the spectra of metric perturbations and thereby a means of constraining the
inflationary potential. The relation between the metric perturbations and CBR
anisotropy depends upon cosmological parameters -- most notably the possibility
of a cosmological constant. Motivated by some observational evidence for a
cosmological constant (large-scale structure, cluster-baryon fraction,
measurements of the Hubble constant and age of the Universe) we derive the
reconstruction equations and consistency relation to second order in the
presence of a cosmological constant. We also clarify previous notation and
discuss alternative schemes for reconstruction.Comment: 15 pages, LaTeX, 3 postscript figures (included with epsf), submitted
to Phys. Rev.
wormholes and topological charge
I investigate solutions to the Euclidean Einstein-matter field equations with
topology in a theory with a massless periodic scalar
field and electromagnetism. These solutions carry winding number of the
periodic scalar as well as magnetic flux. They induce violations of a
quasi-topological conservation law which conserves the product of magnetic flux
and winding number on the background spacetime. I extend these solutions to a
model with stable loops of superconducting cosmic string, and interpret them as
contributing to the decay of such loops.Comment: 18 pages (includes 6 figs.), harvmac and epsf, CU-TP-62
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