4,519 research outputs found
Enhancement of the annihilation of dark matter in a radiative seesaw model
The radiative seesaw model with an inert doublet has been shown to be
attractive from a viewpoint of both neutrino masses and cold dark matter.
However, if we apply this model to the explanation of the positron excess in
the cosmic ray observed by PAMELA, a huge boost factor is required although it
can be automatically explained that no anti-proton excess has been observed
there. We consider an extension of the model to enhance the thermally averaged
annihilation cross section without changing the features of the model favored
by both the neutrino oscillation and the relic abundance of dark matter. It is
shown that the data of PAMELA and Fermi-LAT can be well explained in this
extended model. Constraints from gamma ray observations are also discussed.Comment: 28 pages, 5 figures, final version for publicatio
The SEALS Yardsticks for Ontology Management
This paper describes the rst SEALS evaluation campaign
over ontology engineering tools (i.e., the SEALS Yardsticks for Ontology Management). It presents the dierent evaluation scenarios dened to evaluate the conformance, interoperability and scalability of these tools, and the test data used in these scenarios
Characterization and analysis of azimuthally sensitive correlations
A unified framework for describing the azimuthal dependence of two-particle
correlations in heavy-ion collisions is introduced, together with the methods
for measuring the corresponding observables. The generalization to azimuthal
correlations between more than two particles is presented.Comment: 7 pages; talk given at Hot Quarks 2004, Taos (NM), July 18-24,200
Mapping Muscles Activation to Force Perception during Unloading
It has been largely proved that while judging a force humans mainly rely on the motor commands produced to interact with that force (i.e., sense of effort). Despite of a large bulk of previous investigations interested in understanding the contributions of the descending and ascending signals in force perception, very few attempts have been made to link a measure of neural output (i.e., EMG) to the psychophysical performance. Indeed, the amount of correlation between EMG activity and perceptual decisions can be interpreted as an estimate of the contribution of central signals involved in the sensation of force. In this study we investigated this correlation by measuring the muscular activity of eight arm muscles while participants performed a quasi-isometric force detection task. Here we showed a method to quantitatively describe muscular activity ("muscle-metric function") that was directly comparable to the description of the participants' psychophysical decisions about the stimulus force. We observed that under our experimental conditions, muscle-metric absolute thresholds and the shape of the muscle-metric curves were closely related to those provided by the psychophysics. In fact a global measure of the muscles considered was able to predict approximately 60% of the perceptual decisions total variance. Moreover the inter-subjects differences in psychophysical sensitivity showed high correlation with both participants' muscles sensitivity and participants' joint torques. Overall, our findings gave insights into both the role played by the corticospinal motor commands while performing a force detection task and the influence of the gravitational muscular torque on the estimation of vertical forces
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