Square vortex solitons with a large angular momentum

We show the existence of square shaped optical vortices with a large value of the angular momentum hosted in finite size laser beams which propagate in nonlinear media with a cubic-quintic nonlinearity. The light profiles take the form of rings with sharp boundaries and variable sizes depending on the power carried. Our stability analysis shows that these light distributions remain stable when propagate, probably for unlimited values of the angular momentum, provided the hosting beam is wide enough. This happens if the peak amplitude approaches a critical value which only depends on the nonlinear refractive index of the material. A variational approach allows us to calculate the main parameters involved. Our results add extra support to the concept of surface tension of light beams that can be considered as a trace of the existence of a liquid of light.Comment: 6 pages, 6 figures, submitted to Phys. Rev.

Electron detachment from negative ions in bichromatic laser field

Negative ion detachment in two-colour laser field is considered within the recent modification of Keldysh model which makes it quantitatively reliable. The general approach is illustrated by calculation of angular differential detachment rates, partial rates for particular ATD (Above Threshold Detachment) channels and total detachment rates for H$^-$ ion in bichromatic field with 1:2 frequency ratio. Both perturbative and strong field regimes are examined. Polar asymmetry and phase effects are quantitatively characterized with some new features revealed. Phase effects are found to result in a huge anisotropy factor $\sim 10^3$ in the electron angular distribution in the perturbative regime.Comment: 13 pages, 8 figures in separate files which are not incorporated in the latex file of the pape

90TH ANNIVERSARY OF THE UNION OF PEDIATRICIANS OF RUSSIA

The article is dedicated to the 90th anniversary of the Union of Pediatricians of Russia. Studying the results of academic research, reports,  and resolutions  of congresses  and conferences  of Pediatrician  Societies,  it was observed  that discussions  organized  on pediatric forums which brought up actual problems occurring in pediatrics and clinical practice play an important role in decreasing the rate of child mortality and morbidity, saving millions of child lives in the USSR and modern Russia

Creation, doubling, and splitting, of vortices in intracavity second harmonic generation

We demonstrate generation and frequency doubling of unit charge vortices in a linear astigmatic resonator. Topological instability of the double charge harmonic vortices leads to well separated vortex cores that are shown to rotate, and become anisotropic, as the resonator is tuned across resonance

Solution to the Informatization Problem of Geographical Education in Schools on the Basis of Electronic Cartographical Training Manuals

Розглянуто електронні навчальні картографічні посібники як сучасні моделі представлення знань, сучасні технології розробки та функціональні можливості, проаналізовано новітні технічні досягнення у навчальному процесі. Розкрито основні вимоги до цього виду навчальної картографічної продукції, а також інноваційні педагогічні методи та прийоми, що забезпечують електронні картографічні посібники. Electronic cartographic training manuals are considered as modern model of knowledge representation, technology of their design and features is researched, the latest technological advances in the educational process are reviewed. Disclosure of the basic requirements for this type of training cartographic products, as well as new teaching methods and techniques that provide electronic cartographic materials.Роботу виконано на кафедрі геодезії, землевпорядкування і кадастру ВНУ ім. Лесі Українки та кафедрі геодезії і картографії КНУ ім. Т. Шевченк

Evolutionarily new sequences expressed in tumors

BACKGROUND: Earlier we suggested the concept of the positive evolutionary role of tumors. According to this concept, tumors provide conditions for the expression of evolutionarily new and/or sleeping genes in their cells. Thus, tumors are considered as evolutionary proving ground or reservoir of expression. To support this concept we have previously characterized in silico and experimentally a new class of human tumor-related transcribed sequences. RESULTS: In this article we describe results of further studies of previously described tumor-related sequences. The results of molecular phylogeny studies, Southern hybridization experiments and computational comparison with genomes of other species are presented. CONCLUSION: These results suggest that these previously described tumor-related human transcripts are also relatively evolutionarily new

Laser in the axial electric field as a tool to search for P-, T- invariance violation

We consider rotation of polarization plane of the laser light when a gas laser is placed in a longitudinal electric field (10~kV/cm). It is shown that residual anisotropy of the laser cavity 10^{-6} and the sensitivity to the angle of polarization plane rotation about 10^{-11} -10^{-12} rad allows one to measure an electron EDM with the sensitivity about 10^{-30} e cm.Comment: 12 page

Lithologic-facies and paleogeographic features of Mid-Upper Jurassic oil-gas bearing sediments in Nurolsk depression (Western Siberia)

Bathonian-Callovian-Oxfordian sedimentation environment reconstruction in SE Nurolsk depression, Western Siberia has been described. Paleogeographic and litho-geochemical features of sediments, numerous plant remains and ichnofossils indicated the fact that this territory during the Naunaksk suite formation was the transition in-situ sedimentogenesis. Based on the integrated research data, the potential litho-facies were identified in the Mid-Upper sediments within Nurolsk depression, Western Siberia