413 research outputs found
The Age Of Common Sense: The Bible or Modernism--Which?
https://digitalcommons.acu.edu/crs_books/1397/thumbnail.jp
Charge Asymmetry in 1-1000 GeV Electromagnetic Showers and Possibility of Its Measurementnt
For the high energy electromagnetic showers the thickness dependence of a)
the development of electron and positron components, b) the difference between
the secondary electron and positron numbers, c) the charge asymmetry of high
energy electromagnetic showers, as well as d) the spectral distributions of the
components at the shower maxima for various energies of primary particle
energies,1 - 1000 GeV were investigated employing GEANT Monte Carlo simulation
package. Using these simulation results it is discussed the possibility of
observation and study of the charge asymmetry with the help of a magnetic
spectrometer which is important for the current and future experiments on the
detection of radiowaves produced by high energy neutrinos.Comment: TEX file and 4 figure
Bogoliubov-Cerenkov radiation in a Bose-Einstein condensate flowing against an obstacle
We study the density modulation that appears in a Bose-Einstein condensate
flowing with supersonic velocity against an obstacle. The experimental density
profiles observed at JILA are reproduced by a numerical integration of the
Gross-Pitaevskii equation and then interpreted in terms of Cerenkov emission of
Bogoliubov excitations by the defect. The phonon and the single-particle
regions of the Bogoliubov spectrum are respectively responsible for a conical
wavefront and a fan-shaped series of precursors
Finite temperature Cherenkov radiation in the presence of a magnetodielectric medium
A canonical approach to Cherenkov radiation in the presence of a
magnetodielectric medium is presented in classical, nonrelativistic and
relativistic quantum regimes. The equations of motion for the canonical
variables are solved explicitly for both positive and negative times. Maxwell
and related constitute equations are obtained. In the large-time limit, the
vector potential operator is found and expressed in terms of the medium
operators. The energy loss of a charged particle, emitted in the form of
radiation, in finite temperature is calculated. A Dirac equation concerning the
relativistic motion of the particle in presence of the magnetodielectric medium
is derived and the relativistic Cherenkov radiation at zero and finite
temperature is investigated. Finally, it is shown that the Cherenkov radiation
in nonrelativistic and relativistic quantum regimes, unlike its classical
counterpart, introduces automatically a cutoff for higher frequencies beyond
which the power of radiation emission is zero.Comment: To be appear in PR
Effect of Disorder on Ultrafast Exciton Dynamics Probed by Single Molecule Spectroscopy
We present a single-molecule study unraveling the effect of static disorder on the vibrational-assisted ultrafast exciton dynamics in multichromophoric systems. For every single complex, we probe the initial exciton relaxation process by an ultrafast pump-probe approach and the coupling to vibrational modes by emission spectra, while fluorescence lifetime analysis measures the amount of static disorder. Exploiting the wide range of disorder found from complex to complex, we demonstrate that static disorder accelerates the dephasing and energy relaxation rate of the exciton
Evaluation of a Simulation-Based Training Program on Childhood Trauma with Occupational Therapy Students
An educational and simulation-based training model, the Professional ACEs-Informed Training for Health Professionals designed for allied health students was evaluated using a pre-and-post design. The training model emphasizes trauma-informed care and uses social simulation to educate and train students with skills to address adverse childhood experiences. This study evaluated occupational therapy students’ (N=70) levels of self-efficacy and knowledge of trauma-informed care at both pre- and post-training. Analysis of variance results indicated a statistically significant improvement in students’ levels of general self-efficacy and knowledge from pre- to post-assessment (p \u3c .01). These results are suggestive of the usefulness of brief didactics combined with simulation to educate occupational therapy students on adverse childhood experiences and trauma-informed care
Interleukin 12p40 is required for dendritic cell migration and T cell priming after Mycobacterium tuberculosis infection
Migration of dendritic cells (DCs) to the draining lymph node (DLN) is required for the activation of naive T cells. We show here that migration of DCs from the lung to the DLN after Mycobacterium tuberculosis (Mtb) exposure is defective in mice lacking interleukin (IL)-12p40. This defect compromises the ability of IL-12p40–deficient DCs to activate naive T cells in vivo; however, DCs that express IL-12p40 alone can activate naive T cells. Treatment of IL-12p40–deficient DCs with IL-12p40 homodimer (IL-12(p40)2) restores Mtb-induced DC migration and the ability of IL-12p40–deficient DCs to activate naive T cells. These data define a novel and fundamental role for IL-12p40 in the pathogen-induced activation of pulmonary DCs
Slow group velocity and Cherenkov radiation
We theoretically study the effect of ultraslow group velocities on the
emission of Vavilov-Cherenkov radiation in a coherently driven medium. We show
that in this case the aperture of the group cone on which the intensity of the
radiation peaks is much smaller than that of the usual wave cone associated
with the Cherenkov coherence condition. We show that such a singular behaviour
may be observed in a coherently driven ultracold atomic gas.Comment: 4 pages, 4 figure
Characterization of neutrino signals with radiopulses in dense media through the LPM effect
We discuss the possibilities of detecting radio pulses from high energy
showers in ice, such as those produced by PeV and EeV neutrino interactions. It
is shown that the rich radiation pattern structure in the 100 MHz to few GHz
allows the separation of electromagnetic showers induced by photons or
electrons above 100 PeV from those induced by hadrons. This opens up the
possibility of measuring the energy fraction transmitted to the electron in a
charged current electron neutrino interaction with adequate sampling of the
angular distribution of the signal. The radio technique has the potential to
complement conventional high energy neutrino detectors with flavor information.Comment: 5 pages, 4 ps figures. Submitted to Phys. Rev. Let
Self-amplified Cherenkov radiation from a relativistic electron in a waveguide partially filled with a laminated material
The radiation from a relativistic electron uniformly moving along the axis of
cylindrical waveguide filled with laminated material of finite length is
investigated. Expressions for the spectral distribution of radiation passing
throw the transverse section of waveguide at large distances from the laminated
material are derived with no limitations on the amplitude and variation profile
of the layered medium permittivity and permeability. Numerical results for
layered material consisting of dielectric plates alternated with vacuum gaps
are given. It is shown that at a special choice of problem parameters,
Cherenkov radiation generated by the relativistic electron inside the plates is
self-amplified. The visual explanation of this effect is given and a possible
application is discussed.Comment: 8 pages, 4 figures,1 table, the paper is accepted for publication in
the Journal of Physics: Conference Serie
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