443 research outputs found
Purity-bounded uncertainty relations in multidimensional space -- generalized purity
Uncertainty relations for mixed quantum states (precisely, purity-bounded
position-momentum relations, developed by Bastiaans and then by Man'ko and
Dodonov) are studied in general multi-dimensional case. An expression for
family of mixed states at the lower bound of uncertainty relation is obtained.
It is shown, that in case of entropy-bounded uncertainty relations, lower-bound
state is thermal, and a transition from one-dimensional problem to
multi-dimensional one is trivial. Results of numerical calculation of the
relation lower bound for different types of generalized purity are presented.
Analytical expressions for general purity-bounded relations for highly mixed
states are obtained.Comment: 12 pages, 2 figures. draft version, to appear in J. Phys. A Partially
based on a poster "Multidimensional uncertainty relations for states with
given generalized purity" presented on X Intl. Conf. on Quantum Optics'2004
(Minsk, Belarus, May 30 -- June 3, 2004) More actual report is to be
presented on ICSSUR-2005, Besan\c{c}on, France and on EQEC'05, Munich. V. 5:
amended article after referees' remark
New uncertainty relations for tomographic entropy: Application to squeezed states and solitons
Using the tomographic probability distribution (symplectic tomogram)
describing the quantum state (instead of the wave function or density matrix)
and properties of recently introduced tomographic entropy associated with the
probability distribution, the new uncertainty relation for the tomographic
entropy is obtained. Examples of the entropic uncertainty relation for squeezed
states and solitons of the Bose--Einstein condensate are considered.Comment: 18 pages, 2 figures, to be published in European Physical Journal
Dysarthria as a Cause of Hypotonic Dysphonia in Adolescents
В статье рассматривается патология голосового аппарата и причины развития гипотонусной дисфонии у подростков.The main tool of a person in society is a voice that makes communicative activity and social interaction possible. Dysphonia is a disorder of voice production, which impairs the quality of voice. Therefore, the responsibility for the formation of the voice function in adolescents with speech pathology falls on logopedists as specialists in the field of speech and voice production, and the prevention and treatment of voice disorders is carried out by a doctor-otorhinolaryngologist and/or phoniatrist
Time dependence of the electron and positron components of the cosmic radiation measured by the PAMELA experiment between July 2006 and December 2015
Cosmic-ray electrons and positrons are a unique probe of the propagation of
cosmic rays as well as of the nature and distribution of particle sources in
our Galaxy. Recent measurements of these particles are challenging our basic
understanding of the mechanisms of production, acceleration and propagation of
cosmic rays. Particularly striking are the differences between the low energy
results collected by the space-borne PAMELA and AMS-02 experiments and older
measurements pointing to sign-charge dependence of the solar modulation of
cosmic-ray spectra. The PAMELA experiment has been measuring the time variation
of the positron and electron intensity at Earth from July 2006 to December 2015
covering the period for the minimum of solar cycle 23 (2006-2009) till the
middle of the maximum of solar cycle 24, through the polarity reversal of the
heliospheric magnetic field which took place between 2013 and 2014. The
positron to electron ratio measured in this time period clearly shows a
sign-charge dependence of the solar modulation introduced by particle drifts.
These results provide the first clear and continuous observation of how drift
effects on solar modulation have unfolded with time from solar minimum to solar
maximum and their dependence on the particle rigidity and the cyclic polarity
of the solar magnetic field.Comment: 11 pages, 2 figure
Комплексное лечение больных с локализованными и местнораспространенными формами почечно-клеточного рака с применением предоперационной эмболизации
Background: Treatment of localized and locally advanced renal cancer is still of current importance. Subjects and methods: 100 cases of pT2, pT3a renal cell carcinoma were compared in 2 groups according to the treatment strategy: 1) patients who had received complex treatment (renal artery embolization and surgical treatment) (a study group) and 2) those who had been surgically treated (a control group). The criterion for efficiency was the median duration of relapse- free survival. Results: the median duration of relapse-free survival was 37 months in study group patients with pT2 disease and 39.5 months in the control group. The relapse-free survival varies greatly: 30.5 months in patients with pT3a in the study group and 16.5 months in the control group. Conclusion: The findings have led to the conclusion that it is necessary to make preoperative renal artery embolization in the complex treatment of patients with pT3a renal cell carcinoma.
Trapped proton fluxes at low Earth orbits measured by the PAMELA experiment
We report an accurate measurement of the geomagnetically trapped proton
fluxes for kinetic energy above > 70 MeV performed by the PAMELA mission at low
Earth orbits (350-610 km). Data were analyzed in the frame of the adiabatic
theory of charged particle motion in the geomagnetic field. Flux properties
were investigated in detail, providing a full characterization of the particle
radiation in the South Atlantic Anomaly region, including locations, energy
spectra and pitch angle distributions. PAMELA results significantly improve the
description of the Earth's radiation environment at low altitudes placing
important constraints on the trapping and interaction processes, and can be
used to validate current trapped particle radiation models.Comment: 22 pages, 5 figure
Measurement of boron and carbon fluxes in cosmic rays with the PAMELA experiment
The propagation of cosmic rays inside our galaxy plays a fundamental role in
shaping their injection spectra into those observed at Earth. One of the best
tools to investigate this issue is the ratio of fluxes for secondary and
primary species. The boron-to-carbon (B/C) ratio, in particular, is a sensitive
probe to investigate propagation mechanisms. This paper presents new
measurements of the absolute fluxes of boron and carbon nuclei, as well as the
B/C ratio, from the PAMELA space experiment. The results span the range 0.44 -
129 GeV/n in kinetic energy for data taken in the period July 2006 - March
2008
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