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Toward a taxonomic model of attention in effortful listening
In recent years, there has been increasing interest in studying listening effort. Research on listening effort intersects with the development of active theories of speech perception and contributes to the broader endeavor of understanding speech perception within the context of neuroscientific theories of perception, attention, and effort. Due to the multidisciplinary nature of the problem, researchers vary widely in their precise conceptualization of the catch-all term listening effort. Very recent consensus work stresses the relationship between listening effort and the allocation of cognitive resources, providing a conceptual link to current cognitive neuropsychological theories associating effort with the allocation of selective attention. By linking listening effort to attentional effort, we enable the application of a taxonomy of external and internal attention to the characterization of effortful listening. More specifically, we use a vectorial model to decompose the demand causing listening effort into its mutually orthogonal external and internal components and map the relationship between demanded and exerted effort by means of a resource-limiting term that can represent the influence of motivation as well as vigilance and arousal. Due to its quantitative nature and easy graphical interpretation, this model can be applied to a broad range of problems dealing with listening effort. As such, we conclude that the model provides a good starting point for further research on effortful listening within a more differentiated neuropsychological framework
Prospects for identifying the sources of the Galactic cosmic rays with IceCube
We quantitatively address whether IceCube, a kilometer-scale neutrino
detector under construction at the South Pole, can observe neutrinos pointing
back at the accelerators of the Galactic cosmic rays. The photon flux from
candidate sources identified by the Milagro detector in a survey of the TeV sky
is consistent with the flux expected from a typical cosmic-ray generating
supernova remnant interacting with the interstellar medium. We show here that
IceCube can provide incontrovertible evidence of cosmic-ray acceleration in
these sources by detecting neutrinos. We find that the signal is optimally
identified by specializing to events with energies above 30 TeV where the
atmospheric neutrino background is low. We conclude that evidence for a
correlation between the Milagro and IceCube sky maps should be conclusive after
several years.Comment: 5 pages, 5 figures; part of the text and some figures have changed,
conclusions remain the same; equals journal versio
Direct Simulation Monte Carlo for Thin Film Bearings
The direct simulation Monte Carlo (DSMC) scheme is used to study the gas flow under a read/write head positioned nanometers above a moving disk drive platter (the slider bearing problem). In most cases, impressive agreement is found between the particle-based simulation and numerical solutions of the continuum hydrodynamic Reynolds equation which has been corrected for slip. However, at very high platter speeds the gas is far from equilibrium, and the load capacity for the slider bearing cannot be accurately computed from the hydrodynamic pressure
Equation-free implementation of statistical moment closures
We present a general numerical scheme for the practical implementation of
statistical moment closures suitable for modeling complex, large-scale,
nonlinear systems. Building on recently developed equation-free methods, this
approach numerically integrates the closure dynamics, the equations of which
may not even be available in closed form. Although closure dynamics introduce
statistical assumptions of unknown validity, they can have significant
computational advantages as they typically have fewer degrees of freedom and
may be much less stiff than the original detailed model. The closure method can
in principle be applied to a wide class of nonlinear problems, including
strongly-coupled systems (either deterministic or stochastic) for which there
may be no scale separation. We demonstrate the equation-free approach for
implementing entropy-based Eyink-Levermore closures on a nonlinear stochastic
partial differential equation.Comment: 7 pages, 2 figure
The Waiting And Mating Game: Condition Dependent Mate Sampling In Female Gray Treefrogs (Hyla Versicolor)
Strong sexual selection by receivers can lead to the evolution of elaborate courtship behaviors in signalers. However the process by which receivers sample signalers and execute mate choice under complex signaling conditions—and thus the realized strength of sexual section—is poorly understood. Moreover, receivers can vary in condition, which can further influence mate sampling strategies. Using wild female frogs we tested two hypotheses at the intersection of these important problems: that some of the individual variation in mate sampling is explained by (1) the reproductive urgency hypothesis, which predicts that receivers in a more urgent reproductive state will sample mates less and/or (2) the reproductive investment hypothesis, which predicts that receivers that have invested less in the current reproductive effort will sample mates less. Eastern gray treefrogs, Hyla versicolor, were collected in amplexus and repeatedly tested for phonotaxis behavior using a dynamic playback assay. To evaluate if hormonal mechanisms explained variation in the mate sampling, three steroid hormones, estradiol, progesterone, and corticosterone, were collected using a noninvasive water-borne hormone assay, validated for this species in the present study. Finally, we measured clutch size (investment) and the duration of time required for each female to oviposit after being reunited with their male mate (urgency). We found repeatability in many of the behaviors, including mate sampling. We found that females with higher concentrations estradiol and corticosterone made quicker choices, and that females with higher progesterone sampled mates more. We also found that female frogs in a more urgent reproductive state had lower concentrations of progesterone and estradiol, thereby providing the first evidence of a relationship between gonadal hormones and reproductive urgency. Collectively we found some support for the reproductive urgency but not the investment hypothesis. Thus, even though a female frog\u27s reproductive readiness is a highly transient life history stage, fine scale variation in her reproductive timeline could mitigate the strength of directional selection
Turbulence Fluctuations and New Universal Realizability Conditions in Modelling
General turbulent mean statistics are shown to be characterized by a
variational principle. The variational functionals, or ``effective actions'',
have experimental consequences for turbulence fluctuations and are subject to
realizability conditions of positivity and convexity. An efficient
Rayleigh-Ritz algorithm is available to calculate approximate effective actions
within PDF closures. Examples are given for Navier-Stokes and for a 3-mode
system of Lorenz. The new realizability conditions succeed at detecting {\em a
priori} the poor predictions of PDF closures even when the classical 2nd-order
moment realizability conditions are satisfied.Comment: 4 pages, LaTeX (Version 2.09), 3 figures, Postscript, Submitted to
Phys. Rev. Let
Who Wears the MAGA Hat? Racial Beliefs and Faith in Trump
On the basis of a 2019 YouGov survey of white respondents (n = 734), the impact of racial beliefs on support for Donald Trump was explored. The analysis revealed that in addition to racial resentment, white nationalism—a desire to keep the United States white demographically and culturally—was strongly related to faith in Trump. Analyses based on a 2019 Amazon Mechanical Turk survey yielded similar results and also showed that white nationalism increased willingness to wear a MAGA hat. Future research on the political consequences of racial beliefs should focus on what whites think not only of blacks but also of themselves
Redemption at a Correctional Turning Point: Public Support for Rehabilitation Ceremonies
The authors studied the extent to which the American public would support the implementation of rehabilitation ceremonies, including certificates. Using a national-level survey they commissioned YouGov to undertake, the authors examined public views about the redeemability of offenders--whether they believe that those convicted of felonies are intractably criminal or have the potential to change for the better. Results of the survey indicate substantial belief in offender redeemability and support for rehabilitation ceremonies and certificates
Rayleigh-Ritz Calculation of Effective Potential Far From Equilibrium
We demonstrate the utility of a Rayleigh-Ritz scheme recently proposed to
compute the nonequilibrium effective potential nonperturbatively in a strong
noise regime far from equilibrium. A simple Kramers model of an ionic conductor
is used to illustrate the efficiency of the method.Comment: 4 pages, Latex (Version 2.09), 2 figures (Postscript),
tar+gzip+uuencoded. Submitted to Phys. Rev. Let
The Baldwin Effect and Black Hole Accretion: A Spectral Principal Component Analysis of a Complete QSO Sample
A unique set of UV-optical spectrograms of 22 low redshift QSOs are
investigated using principal component analysis. We find three significant
principal components over the broad wavelength range from Ly\alpha to H\alpha.
They together account for about 78% of the sample intrinsic variance. We
present strong arguments that the first principal component represents the
Baldwin effect, relating equivalent widths to the luminosity (i.e. accretion
rate), but only emission-line cores are involved. The second component
represents continuum variations, probably dominated by intrinsic reddening. The
third principal component directly relates QSO UV properties to the optical
principal component 1 found by Boroson & Green (1992). It is the primary cause
of scatter in the Baldwin relationships. It is also directly related to broad
emission-line width and soft X-ray spectral index, and therefore probably
driven by Eddington accretion ratio. We demonstrate how Baldwin relationships
can be derived using our first principal component, virtually eliminating the
scatter caused by the third principal component. This rekindles the hope that
the Baldwin relationships can be used for cosmological study.Comment: 35 pages, 13 figures, AASTEX, accepted for publication in Ap
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