Unified theory of bound and scattering molecular Rydberg states as quantum maps

Using a representation of multichannel quantum defect theory in terms of a quantum Poincar\'e map for bound Rydberg molecules, we apply Jung's scattering map to derive a generalized quantum map, that includes the continuum. We show, that this representation not only simplifies the understanding of the method, but moreover produces considerable numerical advantages. Finally we show under what circumstances the usual semi-classical approximations yield satisfactory results. In particular we see that singularities that cause problems in semi-classics are irrelevant to the quantum map

Microwave fidelity studies by varying antenna coupling

The fidelity decay in a microwave billiard is considered, where the coupling to an attached antenna is varied. The resulting quantity, coupling fidelity, is experimentally studied for three different terminators of the varied antenna: a hard wall reflection, an open wall reflection, and a 50 Ohm load, corresponding to a totally open channel. The model description in terms of an effective Hamiltonian with a complex coupling constant is given. Quantitative agreement is found with the theory obtained from a modified VWZ approach [Verbaarschot et al, Phys. Rep. 129, 367 (1985)].Comment: 9 pages 5 figur

Decoherence of spin echoes

We define a quantity, the so-called purity fidelity, which measures the rate of dynamical irreversibility due to decoherence, observed e.g in echo experiments, in the presence of an arbitrary small perturbation of the total (system + environment) Hamiltonian. We derive a linear response formula for the purity fidelity in terms of integrated time correlation functions of the perturbation. Our relation predicts, similarly to the case of fidelity decay, faster decay of purity fidelity the slower decay of time correlations is. In particular, we find exponential decay in quantum mixing regime and faster, initially quadratic and later typically gaussian decay in the regime of non-ergodic, e.g. integrable quantum dynamics. We illustrate our approach by an analytical calculation and numerical experiments in the Ising spin 1/2 chain kicked with tilted homogeneous magnetic field where part of the chain is interpreted as a system under observation and part as an environment.Comment: 22 pages, 10 figure

Cognitive Behavioral Therapy for Anxiety Disorders in Youth

Cognitive behavioral therapies (CBTs) have been shown to be efficacious for the treatment of anxiety disorders in children and adolescents. Randomized clinical trials indicate that approximately two-thirds of children treated with CBT will be free of their primary diagnosis at posttreatment. Although several CBT treatment packages have been investigated in youth with diverse anxiety disorders, common core components have been identified. A comprehensive assessment, development of a good therapeutic relationship and working alliance, cognitive restructuring, repeated exposure with reduction of avoidance behavior, and skills training comprise the core procedures for the treatment of anxiety disorders in youth

Learning goal orientation and psychological capital among students: A pathway to academic satisfaction and performance

This study explores the mediating role of psychological capital (PsyCap) in the association between learning goal orientation (LGO), academic satisfaction, and performance among college students. We suggest that PsyCap provides positive psychological resources through which learning‐oriented students sustain the effort in academic achievement situations, contributing to academic satisfaction and performance. Seven hundred and sixty‐eight (n = 768) college students completed an academic well‐being survey, including LGO, PsyCap, and academic satisfaction measures. Academic performance was collected 5 months later from the University academic records of students. Path analysis results showed that LGO was directly related to academic satisfaction and performance and indirectly related through PsyCap. Statistically significant indirect effects showed a partial mediation. These results highlight the importance of positive education through investment in psychological resources to increase performance and satisfaction among college students

Avalanches and the Distribution of Reconnection Events in Magnetized Circumstellar Disks

Cosmic rays produced by young stellar objects can potentially alter the ionization structure, heating budget, chemical composition, and accretion activity in circumstellar disks. The inner edges of these disks are truncated by strong magnetic fields, which can reconnect and produce flaring activity that accelerates cosmic radiation. The resulting cosmic rays can provide a source of ionization and produce spallation reactions that alter the composition of planetesimals. This reconnection and particle acceleration are analogous to the physical processes that produce flaring in and heating of stellar coronae. Flaring events on the surface of the Sun exhibit a power-law distribution of energy, reminiscent of those measured for Earthquakes and avalanches. Numerical lattice-reconnection models are capable of reproducing the observed power-law behavior of solar flares under the paradigm of self-organized criticality. One interpretation of these experiments is that the solar corona maintains a nonlinear attractor -- or ``critical'' -- state by balancing energy input via braided magnetic fields and output via reconnection events. Motivated by these results, we generalize the lattice-reconnection formalism for applications in the truncation region of magnetized disks. Our numerical experiments demonstrate that these nonlinear dynamical systems are capable of both attaining and maintaining criticality in the presence of Keplerian shear and other complications. The resulting power-law spectrum of flare energies in the equilibrium attractor state is found to be nearly universal in magnetized disks. This finding indicates that magnetic reconnection and flaring in the inner regions of circumstellar disks occur in a manner similar to activity on stellar surfaces

An analogue study examining Attitude Change Theory and its implications for dissemination and implementation of empirically supported treatments

Despite the promise of research-based treatments, dissemination into community settings has been problematic. Attitudes toward these treatments may be partially responsible for the slow uptake. Building on the functional theory of attitudes, it was hypothesized that presenting emotion-focused rather than cognitively-focused information about a treatment would produce more positive attitudes toward the treatment in individuals interested in clinical practice. To test this hypothesis, 144 students (116 women; Mage = 22.46 years) completed a measure of vocational interest and evaluated a treatment after reading either an emotional or cognitive passage about the treatment. Consistent with the hypothesis, participants’ interests in clinical activities were related to more favorable reactions to the emotional passage but not the cognitive passage. This effect was partially mediated by message elaboration. Findings suggest that presenting clinicians with emotionally rich information on treatment options may help bridge the gap between research and practice

Multi-Country analysis of palm oil consumption and cardiovascular disease mortality for countries at different stages of economic development: 1980-1997

<p>Abstract</p> <p>Background</p> <p>Cardiovascular diseases represent an increasing share of the global disease burden. There is concern that increased consumption of palm oil could exacerbate mortality from ischemic heart disease (IHD) and stroke, particularly in developing countries where it represents a major nutritional source of saturated fat.</p> <p>Methods</p> <p>The study analyzed country-level data from 1980-1997 derived from the World Health Organization's Mortality Database, U.S. Department of Agriculture international estimates, and the World Bank (234 annual observations; 23 countries). Outcomes included mortality from IHD and stroke for adults aged 50 and older. Predictors included per-capita consumption of palm oil and cigarettes and per-capita Gross Domestic Product as well as time trends and an interaction between palm oil consumption and country economic development level. Analyses examined changes in country-level outcomes over time employing linear panel regressions with country-level fixed effects, population weighting, and robust standard errors clustered by country. Sensitivity analyses included further adjustment for other major dietary sources of saturated fat.</p> <p>Results</p> <p>In developing countries, for every additional kilogram of palm oil consumed per-capita annually, IHD mortality rates increased by 68 deaths per 100,000 (95% CI [21-115]), whereas, in similar settings, stroke mortality rates increased by 19 deaths per 100,000 (95% CI [-12-49]) but were not significant. For historically high-income countries, changes in IHD and stroke mortality rates from palm oil consumption were smaller (IHD: 17 deaths per 100,000 (95% CI [5.3-29]); stroke: 5.1 deaths per 100,000 (95% CI [-1.2-11.0])). Inclusion of other major saturated fat sources including beef, pork, chicken, coconut oil, milk cheese, and butter did not substantially change the differentially higher relationship between palm oil and IHD mortality in developing countries.</p> <p>Conclusions</p> <p>Increased palm oil consumption is related to higher IHD mortality rates in developing countries. Palm oil consumption represents a saturated fat source relevant for policies aimed at reducing cardiovascular disease burdens.</p