4,355 research outputs found
Spinors for Spinning p-Branes
The group of the p-brane world volume preserving diffeomorphism is
considered. The infinite-dimensional spinors of this group are related, by the
nonlinear realization techniques, to the corresponding spinors of its linear
subgroup, that are constructed explicitly. An algebraic construction of the
Virasoro and Neveu-Schwarz-Ramond algebras, based on this infinite-dimensional
spinors and tensors, is demonstrated.Comment: 18 page
Using the dynamic mapping of the microwave brain radiation for functional studies
In this study, organizational principles of the radiophysical complex are proposed for simultaneous measurements of the brightness temperature fluctuations of the human brain and parameters of the autonomic nervous system. A new structure of the medical microwave radiothermograph is suggested based on the parametric compensation of losses in the circuit elements of the thermobalance. The aim of this article is to justify the structural organization of the radiophysical complex for the recording and joint real-time analysis of processes of the microwave radiation formation in the brain tissue and characteristics of the autonomic nervous system. Description of the radiophysical complex MRTHR with realization of these principles is presented. The peculiarity of the proposed radiophysical complex is in passive elements that do not contain electronic nodes and blocks and are inside the shielded cabin. In order to increase the accuracy of the brightness temperature of the deep brain structures measurement in the radiophysical complex a new structure is implemented. This structure of the medical microwave radiothermograph is based on the parametric compensation of losses in the circuit elements of the thermobalance
Multi-filament structures in relativistic self-focusing
A simple model is derived to prove the multi-filament structure of
relativistic self-focusing with ultra-intense lasers. Exact analytical
solutions describing the transverse structure of waveguide channels with
electron cavitation, for which both the relativistic and ponderomotive
nonlinearities are taken into account, are presented.Comment: 21 pages, 12 figures, submitted to Physical Review
On the full, strongly exceptional collections on toric varieties with Picard number three
We investigate full strongly exceptional collections on smooth, com- plete
toric varieties. We obtain explicit results for a large family of varieties
with Picard number three, containing many of the families already known. We
also describe the relations between the collections and the split of the push
forward of the trivial line bundle by the toric Frobenius morphism
Use of accelerated helium-3 ions for determining oxygen and carbon impurities in some pure materials
Methods are developed for the determination of O impurity in Be and Si carbide and concurrent determination of C and O impurities in Si and W by irradiation with accelerated He-3 ions and subsequent activity measurements of C-11 and F-18 formed from C and O with the aid of a gamma-gamma coincidence spectrometer. Techniques for determining O in Ge and Ga arsenide with radiochemical separation of F-18 are also described
Could One Find Petroleum Using Neutrino Oscillations in Matter?
In neutrino physics, it is now widely believed that neutrino oscillations are
influenced by the presence of matter, modifying the energy spectrum produced by
a neutrino beam traversing the Earth. Here, we will discuss the reverse
problem, i.e. what could be learned about the Earth's interior from a single
neutrino baseline energy spectrum, especially about the Earth's mantle. We will
use a statistical analysis with a low-energy neutrino beam under very
optimistic assumptions. At the end, we will note that it is hard to find
petroleum with such a method, though it is not too far away from technical
feasibility.Comment: 6 pages, 4 figures, EPL LaTeX. Final version to be published in
Europhys. Let
Vortex Polarity Switching in Magnets with Surface Anisotropy
Vortex core reversal in magnetic particle is essentially influenced by a
surface anisotropy. Under the action of a perpendicular static magnetic field
the vortex core undergoes a shape deformationof pillow- or barrel-shaped type,
depending on the type of the surface anisotropy. This deformation plays a key
point in the switching mechanism: We predict that the vortex polarity switching
is accompanied (i) by a linear singularity in case of Heisenberg magnet with
bulk anisotropy only and (ii) by a point singularities in case of surface
anisotropy or exchange anisotropy. We study in details the switching process
using spin-lattice simulations and propose a simple analytical description
using a wired core model, which provides an adequate description of the Bloch
point statics, its dynamics and the Bloch point mediated switching process. Our
analytical predictions are confirmed by spin-lattice simulations for Heisenberg
magnet and micromagnetic simulations for nanomagnet with account of a dipolar
interaction.Comment: 17 pages, 15 figure
Diagnostics and therapy of peripheral neuropathy (literature review)
The review is devoted to diagnostics and treatment of neuropathic pain in patients with peripheral nervous system diseases. Main assessment tools are shown including Visual analog Scale (VAS), Neuropathic Pain Scale (NPS), Leeds Assessment of Neuropathic Symptoms and Signs (LANSS), self-report version of the Leeds Assessment of Neuropathic Symptoms and Signs (S-LANSS), Neuropathic Pain Questionnaire (NPQ), Questionnaire Douleur Neuropathique 4 (DN-4), pain DETECT Questionnaire, Standardized Evaluation of Pain (StEP), identification pain questionnaire (ID-pain), clinical investigation (quantitative sensorial test are included), neurophysiological studies (electroneuromyography, evoked potentials) and MRI. Novel therapy in neuropathic pain disorders is described including both medicamentous and additional therapeutics methods
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