1,940 research outputs found
Critical phenomena in globally coupled excitable elements
Critical phenomena in globally coupled excitable elements are studied by
focusing on a saddle-node bifurcation at the collective level. Critical
exponents that characterize divergent fluctuations of interspike intervals near
the bifurcation are calculated theoretically. The calculated values appear to
be in good agreement with those determined by numerical experiments. The
relevance of our results to jamming transitions is also mentioned.Comment: 4 pages, 3 figure
Transparent and Flexible Thin Film Electroluminescent Devices Using HiTUS Deposition and Laser Processing Fabrication
Highly transparent thin film electroluminescent structures offering excellent switch on characteristics, high luminance and large break-down voltages have been deposited onto glass and flexible polymeric materials with no substrate heating using high target utilization sputtering. Deposition of ZnS:Mn as the active light emitting layer and Y2O3,Al2O3,Ta2O5, and HfO2 as dielectric materials arranged in single and multiple layer configurations were investigated. Devices incorporating Al2O3,HfO2 quadruple layers demonstrate the highest attainable luminance at low threshold voltage. Single pulse excimer laser irradiation of the phosphor layer prior to deposition of the top dielectric layer enhanced the luminance of the devices. The devices fabricated on glass and polymeric substrates exhibited a maximum luminance of 500 and 450 cdm−2 when driven at 270 VRMS and 220 VRMS, respectively, with a 1.0 kHz sine wave
Teaching our children when to eat:how parental feeding practices inform the development of emotional eating-a longitudinal experimental design
Background: Emotional eating in children has been related to the consumption of energy-dense foods and obesity, but the development of emotional eating in young children is poorly understood. Objectives: We evaluated whether emotional eating can be induced in 5-7-y-old children in the laboratory and assessed whether parental use of overly controlling feeding practices at 3-5 y of age predicts a greater subsequent tendency for children to eat under conditions of mild stress at ages 5-7 y. Design: Forty-one parent-child dyads were recruited to participate in this longitudinal study, which involved parents and children being observed consuming a standard lunch, completing questionnaire measures of parental feeding practices, participating in a research procedure to induce child emotion (or a control procedure), and observing children's consumption of snack foods. Results: Children at ages 5-7 y who were exposed to a mild emotional stressor consumed significantly more calories from snack foods in the absence of hunger than did children in a control group. Parents who reported the use of more food as a reward and restriction of food for health reasons with their children at ages 3-5 y were more likely to have children who ate more under conditions of negative emotion at ages 5-7 y. Conclusions: Parents who overly control children's food intake may unintentionally teach children to rely on palatable foods to cope with negative emotions. Additional research is needed to evaluate the implications of these findings for children's food intake and weight outside of the laboratory setting. This trial was registered at clinicaltrials.gov as NCT01122290
Bayes linear kinematics in the analysis of failure rates and failure time distributions
Collections of related Poisson or binomial counts arise, for example, from a number of different failures in similar machines or neighbouring time periods. A conventional Bayesian analysis requires a rather indirect prior specification and intensive numerical methods for posterior evaluations. An alternative approach using Bayes linear kinematics in which simple conjugate specifications for individual counts are linked through a Bayes linear belief structure is presented. Intensive numerical methods are not required. The use of transformations of the binomial and Poisson parameters is proposed. The approach is illustrated in two examples, one involving a Poisson count of failures, the other involving a binomial count in an analysis of failure times
The dependence of intrinsic alignment of galaxies on wavelength using KiDS and GAMA
The outer regions of galaxies are more susceptible to the tidal interactions
that lead to intrinsic alignments of galaxies. The resulting alignment signal
may therefore depend on the passband if the colours of galaxies vary spatially.
To quantify this, we measured the shapes of galaxies with spectroscopic
redshifts from the GAMA survey using deep gri imaging data from the KiloDegree
Survey. The performance of the moment-based shape measurement algorithm DEIMOS
was assessed using dedicated image simulations, which showed that the
ellipticities could be determined with an accuracy better than 1% in all bands.
Additional tests for potential systematic errors did not reveal any issues. We
measure a significant difference of the alignment signal between the g,r and
i-band observations. This difference exceeds the amplitude of the linear
alignment model on scales below 2 Mpc/h. Separating the sample into
central/satellite and red/blue galaxies, we find that that the difference is
dominated by red satellite galaxies.Comment: 16 pages, 13 figures, accepted, to appear in A&
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