606 research outputs found
Observation of polarization quantum noise of laser radiation in Rb vapor cell
We present experimental study of polarization quantum noise of laser
radiation passed through optically think vapor of Rb87. We observe a step-like
noise spectrum. We discuss various factor which may result in such noise
spectrum and prevent observation of squeezing of quantum fluctuations predicted
in Matsko et al. PRA 63, 043814 (2001).Comment: 4 pages, 5 figures. Translated from Russian by I. Novikov
Diffusion-induced Ramsey narrowing
A novel form of Ramsey narrowing is identified and characterized. For
long-lived coherent atomic states coupled by laser fields, the diffusion of
atoms in-and-out of the laser beam induces a spectral narrowing of the atomic
resonance lineshape. Illustrative experiments and an intuitive analytical model
are presented for this diffusion-induced Ramsey narrowing, which occurs
commonly in optically-interrogated systems.Comment: 4 pages, 8 figure
Gaming as Means of Teaching Foreign Language Communication
The problem of using foreign language as means of communication between professionals with different cultural backgrounds is considered. Attention is paid to the communicationoriented and professionally-directed nature of the course of learning a foreign language in not-linguistic high school. The defining characteristics of the learning process organized with gaming using are described. General overview of the typology of pedagogical games is made.Рассматривается проблема использования иностранного языка как средства общения между специалистами, представляющими разные культуры. Уделяется внимание коммуникативно-ориентированному и профессионально-направленному характеру курса обучения иностранному языку в неязыковом вузе. Описываются определяющие характеристики процесса обучения, организованного с использованием гейминга. Выполнен общий обзор типологии педагогических игр
Dynamic optical bistability in resonantly enhanced Raman generation
We report observations of novel dynamic behavior in resonantly-enhanced
stimulated Raman scattering in Rb vapor. In particular, we demonstrate a
dynamic hysteresis of the Raman scattered optical field in response to changes
of the drive laser field intensity and/or frequency. This effect may be
described as a dynamic form of optical bistability resulting from the formation
and decay of atomic coherence. We have applied this phenomenon to the
realization of an all-optical switch.Comment: 4 pages, 5 figure
Formation of Optical Low-dimensional Structures for Photonic Elements
In the present article, the formation of low-dimensional periodic structures with relief repeating the trajectory of movement of an AFM probe were presented. The parameters affecting their geometric dimensions: height, width, uniformity in the layer, etc., were investigated. The method of induced deposition of silver and/or gold clusters on the surface of a Bragg mirror in the presence of an external electric field was developed. The possibility of using such structures in optical elements, photoelectronic converters, optoelectronic devices of fiber optics, as well as the construction of photonic crystals (elements) based on the periodic structures is discussed.
Keywords: nanostructures, the atomic force microscope (AFM), the probe lithograph
Legal regulation of interreligious relations in the field of general education: the ratio of public and private interests
In article on the basis of the formal legal analysis of the national legal system and the international jurisprudence the key principles of state legal regulation of the confessional relations in the sphere of the general education are distinguished; the need of their addition and unification at the national level for the purpose of providing the balanced ratio of public and private interests in the context of providing the integrated rights and personal freedoms is demonstrate
Alien Species in the Flora of the Middle Volga Region
The article presents information on the diversity and structure of the alien flora of the Middle Volga region on the border between the steppe and forest-steppe zones of the European botanical and geographical province. In the studied area, we identified 440 alien species of plants (24.6% of the total floristic diversity), including 59 invasive and potentially invasive species, the dispersal of which has already caused environmental consequences or could become a threat in the future. According to the degree of naturalization, alien plant species among the regional flora are represented by 146 ephemerophytes (33.2%), 122 colonophytes (27.7%), 151 epecophytes (34.3%) and 21 agriophytes (4.8%). As verified via the main method of skidding, alien species are distributed almost equally – 228 xenophytes (51.8%) and 212 ergasiophygophytes (48.2%). It was revealed that of the 150 species of alien plants, there are only 84 of the most common European species in the Middle Volga region, most of which do not show high cenotic activity. The obtained results actualize the development of a system of ecological and economic assessment of the consequences of introducing alien plant species into regional flora.
Keywords: alien plants, invasive species, Middle Volga region, regional flor
Buffer-gas induced absorption resonances in Rb vapor
We observe transformation of the electromagnetically induced transparency
(EIT) resonance into the absorption resonance in a interaction
configuration in a cell filled with Rb and a buffer gas. This
transformation occurs as a one-photon detuning of the coupling fields is varied
from the atomic transition. No such absorption resonance is found in the
absence of a buffer gas. The width of the absorption resonance is several times
smaller than the width of the EIT resonance, and the changes of absorption near
these resonances are about the same. Similar absorption resonances are detected
in the Hanle configuration in a buffered cell.Comment: 11 pages, 15 figures; 13 pages, 17 figures, added numerical
simulatio
Clinical and immunophenotypic aspects of common variable immunodeficiency in adults
Features of expression of differentiation markers of peripheral blood lymphocytes were studied by flow cytofluorimetry in combination with clinical manifestations in 30 adult patients (12 men and 18 women, mean age 37.5±12.3 years) with the established diagnosis of сommon variable immunodeficiency (CVID). The examination of patients was carried out in the period of obvious absence of infectious and inflammatory diseases. It was found that the dominant immunophenotype in adult patients with СVID is an increase in the blood content of T cytotoxic lymphocytes (CD3+CD8+) with high expression of activation markers HLA- DR+ and CD38+ and a decrease in isotype-switched B lymphocytes IgD-27+ (in almost 100% of the examined individuals). The maximum degree of increase in the number of T killers was observed in patients with a low level of B lymphocytes (CD19+ less than 6%, p = 0.005) and a minimum concentration of IgG in the blood serum (less than 2 g/l, p = 0.02). The content of isotype-switched B cells correlated with the level of IgG, as well as the total concentration of serum immunoglobulins A, M and G (p = 0.02; p = 0.003). In adult СVID patients with the combined clinical phenotype “infectious syndrome + autoimmune disease”, the content of isotype-switched B lymphocytes, IgG and the total concentration of Ig in the blood is significantly lower (p = 0.04; p = 0.03 and p = 0.02), and activated T killers with HLA-DR+ and CD38+ expression are higher (p% = 0.01; rabs = 0.02 and p% = 0.004; rabs = 0.001, respectively) compared to patients with isolated infectious – inflammatory syndrome. We also found that among patients with the lowest number of isotype-switched IgD- 27+ B cells (less than 5%) and serum IgG concentration (less than 2 g/l), the incidence of lymphoproliferative syndrome is higher (p = 0.04 and p = 0.01, respectively). Thus, the low content of isotype-switched memory B lymphocytes in peripheral blood is most characteristic of patients with a more severe clinical phenotype of СVID
Peculiarities of anharmonic lattice dynamics and thermodynamics of alkaline-earth metals
The calculations are performed for a broad range of the properties of Ca and
Sr in the fcc and bcc phases. A detailed information on the magnitude and
character of temperature dependence of anharmonic effects in the lattice
dynamics over the entire Brillouin zone (frequency shifts and phonon damping,
Gruneisen parameters) is given. A detailed comparison of the computational
results for the heat capacity and thermal expansion with the experimental data
is carried out; the theoretical results are in good agreement with the
experiment.Comment: 16 pages, 19 Postscript figures, Revte
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