Nonlinear beam tapering and two-dimensional ring solitons.

We examine a possibility to exploit the nonlinear lens effect-the initial stage of self-focusing to localize initially broad field distribution into the small central area where wave collapse is arrested-the nonlinear beam tapering. We describe two-dimensional localized solitary waves (ring solitons) in a physical system that presents a linear medium in the central core, surrounded by the cladding with the focusing Kerr nonlinearity. The standard variational analysis demonstrates that such solitons correspond to the minimum of the Hamiltonian.

[DETERMINATION OF PHYLOGENETIC RELATIONSHIP OF YERSINIA PESTIS STRAINS FROM NATURAL PLAGUE FOCI OF THE CAUCASUS BY MULTI-LO- CUS VNTR-ANALYSIS].

Aim: Determination of the degree of phylogenetic relationship of Yersinia pestis strains iso- lated from the territories of natural foci of plague from the Caucasus using VNTR-typing by 25 loci (MLVA25).

Materials And Methods: 26 strains of Y pestis from Russian natural foci of the Caucasus were used in the study. 25 loci of tandem repeats in Y pestis genome by Le Fleche scheme were used for execution of multi-locus VNTR-analysis.

[EPIZOOTOLOGICAL AND EPIDEMIOLOGICAL ZONING OF THE TERRITORY OF NORTH CAUCASUS FEDERAL REGION BYA DEGREE OF NON-WELFARE BYANTHRAX USING ARC GIS10 PROGRAM].

Aim: Conducting epizootological and epidemiological zoning of the territory ofNorth Caucasus -Federal Region (NCFR) by the degree of non-welfare by anthrax using Arc GIS10 program.

Materials And Methods: 2 parameters were used during zoning ofthe territories of subjects of NCFR (Stavropol Region, Karachaevo-Cherkessia, Kabardino-Balkaria, Chechen, North Ossetia-Alania, Ingushetia, Dagestan Republics) by non-welfare by anthrax: integrated parameter of infection risk and epizootics risk. The parameters were input into the Arc GIS 10 program.

Quantitative characterization of energy absorption in femtosecond laser micro-modification of fused silica.

We present the results of experimental and theoretical study of an energy absorption of femtosecond laser pulse in fused silica. Fundamental and second harmonics of ytterbium laser were used in experiment while general case was considered theoretically and numerically. More efficient absorption at the second harmonics is confirmed both experimentally and numerically.

[Using modern information technology in the practice of the sanitary-epidemiological surveiliance during the XXII Olympic Winter Games and XI Paralympic Winter Games in Sochi].

To improve the sanitary and epidemiological surveillance at the Olympic Games has developed a system of GIS for monitoring objects and situations in the region of Sochi. The system is based on software package ArcGIS, version 10.2 server, with Web-java.

[The epidemiological situation in the Republic of Abkhazia in 2013-2014 and Rospotrebnadzor participation in activities for its stabilization].

Official statistics of Republican SES on infectious diseases are used. The characteristics of the current epidemiological situation in the Republic of Abkhazia is given. The analysis of infectious dis- eases from 2012 to 2014 is presented.

[Use of GIS technologies in development of a cadaster of stationary unfavorable by anthrax points in Krasnodar region].

Aim: Development of a cadaster of stationary unfavorable by anthrax points in Krasnodar region by using GIS technologies.

Materials And Methods: Ageographical information system (GIS) of ESRI program--Arc GIS 10.1 was used for the composition of an electronic cadaster of stationary unfavorable by anthrax points.

[Improvement of epidemiologic control of infectious diseases by using geoinformational systems].

Problems of the perspective of geoinformational systems (GIS) use for improvement of epidemiologic control of infectious diseases including during mass events are examined. A scheme of creation of the decision making support system (DMSS) is proposed, the system is based on GIS, has general primary data and analytical-prognostic tool base including subsystems: real-time primary information intake, information analysis, epizootic and epidemic activity prognosis on the certain territories and the federal level. Specialized personnel training, creation of infrastructure for DMSS functioning in primary Federal Service of Surveillance for Protection of Consumers Rights and Human Welfare units are designated as priority tasks.

Low loss depressed cladding waveguide inscribed in YAG:Nd single crystal by femtosecond laser pulses.

A depressed cladding waveguide with record low loss of 0.12 dB/cm is inscribed in YAG:Nd(0.3at.

Numerical investigation of the impact of reflectors on spectral performance of Raman fibre laser.

Using a cavity mode model we study numerically the impact of bandwidth and spectral response profile of fibre Bragg gratings on four-wave-mixing-induced spectral broadening of radiation generated in 6 km and 22 km SMF-based Raman fibre lasers.

Inscription and characterization of waveguides written into borosilicate glass by a high-repetition-rate femtosecond laser at 800 nm.

A series of waveguides was inscribed in a borosilicate glass (BK7) by an 11 MHz repetition rate femtosecond laser operating with pulse energies from 16 to 30 nJ and focused at various depths within the bulk material. The index modification was measured using a quantitative phase microscopy technique that revealed central index changes ranging from 5 x 10(-3) to 10(-2), leading to waveguides that exhibited propagation losses of 0.2 dB/cm at a wavelength of 633 nm and 0.

Waveguide-saturable absorber fabricated by femtosecond pulses in YAG:Cr(4+) crystal for Q-switched operation of Yb-fiber laser.

A waveguide-saturable absorber with low propagation loss is fabricated by femtosecond pulses in YAG:Cr(4+) crystal. Q-switch operation of a Yb fiber laser with the new saturable absorber having absorption saturation parameters similar to the bulk YAG:Cr(4+) crystal is demonstrated.

270-km ultralong Raman fiber laser.

We analyze the physical mechanisms limiting optical fiber resonator length and report on the longest ever laser cavity, reaching 270 km, which shows a clearly resolvable mode structure with a width of approximately 120 Hz and peak separation of approximately 380 Hz in the radio-frequency spectrum.

Meta-analysis of the efficacy of non-steroidal anti-inflammatory drugs vs. opioids for SWL using modern electromagnetic lithotripters.

Purpose: Clinical studies produce conflicting results on pain relief for shock wave lithotripsy (SWL). We performed a systematic review and meta-analysis to compare non-steroidal anti-inflammatory drugs (NSAIDs) and opioids in pain relief for SWL powered by an electromagnetic generator.

Material And Methods: A search of MEDLINE and EMBASE was performed and all randomized controlled trials comparing NSAIDs and opioids in pain relief for SWL using modern electromagnetic lithotripters were included in the analysis.

Diffractive variable attenuator for femtosecond laser radiation control.

We present a diffractive phase variable attenuator for femtosecond laser radiation control. It allows the control of beam power up to 0.75.

Self-similar core and oscillatory tails of a path-averaged chirped dispersion-managed optical pulse.

We describe the breathing dynamics of the self-similar core and the oscillating tails of a dispersion-managed (DM) soliton. The path-averaged propagation equation governing the shape of the DM soliton in an arbitrary dispersion map is derived. The developed theory correctly predicts the locations of the dips in the tails of the DM soliton.

Chirped solitons with strong confinement in transmission links with in-line fiber Bragg gratings.

We demonstrate that the use of fiber gratings to reverse periodically the pulse chirp in transmission links allows us to produce stable chirped optical solitons with fast-decaying tails. The interaction between neighboring pulses is reduced from that of the usual soliton system as a result of pulse chirping and strong confinement, making possible dense information packing. Such a pulse is an attractive candidate for use as an information carrier in optical transmission systems with ultralarge capacities of approximately 100 Gbits/s.

Symmetries, chirp-free points, and bistability in dispersion-managed fiber lines.

We show from an elementary symmetry analysis that, in dispersion-compensated systems for which a lossless model is valid, nonlinearity requires a chirp-free point at the center of symmetry (if such exists) of the map for any kind of unique periodic solution. We also present an example of a more-complex map when the periodic solution is not unique.

Self-guiding light in layered nonlinear media.

We study the propagation of intense optical beams in layered Kerr media. With appropriate shapes, beams with a power close to the self-focusing threshold are shown to propagate over long distances as quasi-stationary waveguides in cubic media supporting a periodic nonlinear refractive index.

Sub-critical regime of femtosecond inscription.

We apply well known nonlinear diffraction theory governing focusing of a powerful light beam of arbitrary shape in medium with Kerr nonlinearity to the analysis of femtosecond (fs) laser processing of dielectric in sub-critical (input power less than the critical power of self-focusing) regime. Simple analytical expressions are derived for the input beam power and spatial focusing parameter (numerical aperture) that are required for achieving an inscription threshold. Application of non-Gaussian laser beams for better controlled fs inscription at higher powers is also discussed.

Experimental demonstration of mode structure in ultralong Raman fiber lasers.

We present the first experimental demonstration of a resolvable mode structure with spacing c/2nL in the RF spectra of ultralong Raman fiber lasers. The longest ever demonstrated laser cavity (L=84 km), RF peaks of ~100 Hz width and spacing ~1 kHz have been observed at low intracavity powers. The width of the peaks increases linearly with growing intracavity power and is almost independent of fiber length.

Extracorporeal shock wave lithotripsy in the treatment of renal pelvicalyceal stones in morbidly obese patients.

Introduction: Management of urolithiasis in morbidly obese patients is usually associated with higher morbidity and mortality compared to non-obese patients. In morbidly obese patients, since the kidney and stone are at a considerable distance from the skin (compared to non-obese patients) difficulty may be found in positioning the patient so that the stone is situated at the focal point of the lithotripter.

Objective: To evaluate the outcomes and cost-efficiency of extracorporeal shock wave lithotripsy (ESWL) in the treatment of renal pelvicalyceal stones sized between 6 and 20 mm in morbidly obese patients.

Nonstoichiometric hydroxyapatite granules for orthopaedic applications.

A new method for the preparation of nonstoichiometric hydroxyapatite (HA) "dense" and porous granules, round in form and up to 8 mm in sizes designed for application in orthopaedic surgery has been developed. The "dense" granules' porosity was up to 32% and they only contained micropores. They differed from that kind of granules by increased values of compression strength (up to 48 MPa).

Correlations between optimal temporal width and spectral characteristics of an optical signal in a wavelength-paired CS-RZ transmission with high spectral efficiency.

We examine the correlations between the parameters of ultranarrow off-centred filtering and pulse width on the performance of a wavelength paired Nx40Gbit/s DWDM transmission, consisting of carrier suppressed return-to-zero signal with 0.64 bit/s/Hz (without polarizationdivision multiplexing) spectral efficiency.