79 research outputs found
Diurnal cortisol and decision making under risk in problem gambling.
The aim of this study was to assess the influence of diurnal cortisol profile on decision making under risk in individuals with problem gambling and a healthy control group. We examined the relationship between diurnal cortisol, assessed over the course of 2 days, and a battery of tasks that assessed decision making under risk, including the Columbia Card Task and the Cups Task. Thirty individuals with problem gambling and 29 healthy individuals took part in the study. Those with problem gambling showed blunted diurnal cortisol and more risk taking behavior compared with those in the healthy control group. Blunted cortisol profile was associated with more risky behavior and less sensitivity to losing money in problem gambling. These findings suggest that blunted stress physiology plays a role in specific parameters of risky decision making in problem gambling
Low-energy three-body charge transfer reactions with Coulomb interaction in the final state
Three-body charge transfer reactions with Coulomb interaction in the final
state are considered in the framework of coordinate-space integro-differential
Faddeev-Hahn-type equations within two- and six-state close coupling
approximations. The method is employed to study direct muon transfer in
low-energy collisions of the muonic hydrogen H by helium (He) and
lithium (Li) nuclei. The experimentally observed isotopic dependence is
reproduced.Comment: 14 pages REVTeX, accepted for publication in Journal of Physics
Muon Catalyzed Fusion in 3 K Solid Deuterium
Muon catalyzed fusion in deuterium has traditionally been studied in gaseous
and liquid targets. The TRIUMF solid-hydrogen-layer target system has been used
to study the fusion reaction rates in the solid phase of D_2 at a target
temperature of 3 K. Products of two distinct branches of the reaction were
observed; neutrons by a liquid organic scintillator, and protons by a silicon
detector located inside the target system. The effective molecular formation
rate from the upper hyperfine state of and the hyperfine transition
rate have been measured: , and .
The molecular formation rate is consistent with other recent measurements, but
not with the theory for isolated molecules. The discrepancy may be due to
incomplete thermalization, an effect which was investigated by Monte Carlo
calculations. Information on branching ratio parameters for the s and p wave
d+d nuclear interaction has been extracted.Comment: 19 pages, 11 figures, submitted to PRA Feb 20, 199
Measurement of the Resonant Molecular Formation Rate in Solid HD
Measurements of muon-catalyzed dt fusion () in solid
HD have been performed. The theory describing the energy dependent resonant
molecular formation rate for the reaction + HD is
compared to experimental results in a pure solid HD target. Constraints on the
rates are inferred through the use of a Monte Carlo model developed
specifically for the experiment. From the time-of- flight analysis of fusion
events in 16 and 37 targets, an average formation rate
consistent with 0.897(0.046) (0.166) times the
theoretical prediction was obtained.Comment: 4 pages, 5 figure
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