12,226 research outputs found
Unsteady near wall residence times and shear exposure in model distal arterial bypass grafts.
Zero-mode contribution to the light-front Hamiltonian of Yukawa type models
Light-front Hamiltonian for Yukawa type models is determined without the
framework of canonical light-front formalism. Special attention is given to the
contribution of zero modes.Comment: 14 pages, Latex, revised version with minor changes, Submitted to
J.Phys.
Enhanced surface acoustic wave cell sorting by 3D microfluidic chip design
We demonstrate an acoustic wave driven microfluidic cell sorter that combines advantages of multilayer device fabrication with planar surface acoustic wave excitation. We harness the strong vertical component of the refracted acoustic wave to enhance cell actuation by using an asymmetric flow field to increase cell deflection. Precise control of the 3-dimensional flow is realized by topographical structures implemented on the top of the microchannel. We experimentally quantify the effect of the structure dimensions and acoustic parameter. The design attains cell sorting rates and purities approaching those of state of the art fluorescence-activated cell sorters with all the advantages of microfluidic cell sorting
Local Fields without Restrictions on the Spectrum of 4-Momentum Operator and Relativistic Lindblad Equation
Quantum theory of Lorentz invariant local scalar fields without restrictions
on 4-momentum spectrum is considered. The mass spectrum may be both discrete
and continues and the square of mass as well as the energy may be positive or
negative. Such fields can exist as part of a hidden matter in the Universe if
they interact with ordinary fields very weakly. Generalization of
Kallen-Lehmann representation for propagators of these fields is found. The
considered generalized fields may violate CPT- invariance. Restrictions on
mass-spectrum of CPT-violating fields are found. Local fields that annihilate
vacuum state and violate CPT- invariance are constructed in this scope. Correct
local relativistic generalization of Lindblad equation for density matrix is
written for such fields. This generalization is particulary needed to describe
the evolution of quantum system and measurement process in a unique way.
Difficulties arising when the field annihilating the vacuum interacts with
ordinary fields are discussed.Comment: Latex 23 pages, sent to "Foundations of Physics
A functional non-central limit theorem for jump-diffusions with periodic coefficients driven by stable Levy-noise
We prove a functional non-central limit theorem for jump-diffusions with
periodic coefficients driven by strictly stable Levy-processes with stability
index bigger than one. The limit process turns out to be a strictly stable Levy
process with an averaged jump-measure. Unlike in the situation where the
diffusion is driven by Brownian motion, there is no drift related enhancement
of diffusivity.Comment: Accepted to Journal of Theoretical Probabilit
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