Dynamics of platicons due to third-order dispersion

Dynamics of platicons caused by the third-order dispersion is studied. It is shown that under the influence of the third-order dispersion platicons obtain angular velocity depending both on dispersion and on detuning value. A method of tuning of platicon associated optical frequency comb repetition rate is proposed.Comment: 11 pages, 5 figure

Ultra high-Q WGM microspheres from ZBLAN for the mid-IR band

The advantages of high-quality-factor whispering gallery mode microresonators can be applied to develop novel photonic devices for the mid-IR range. ZBLAN (glass based on heavy metal fluorides) is one of the most promising materials to be used for this purpose due to low optical losses in the mid-IR. We developed original fabrication method based on melting of commercially available ZBLAN-based optical fiber to produce high-Q ZBLAN microspheres with the diameters of 250 to 350 $\mu$m. We effectively excited whispering gallery modes in these microspheres and demonstrated high quality factor both at 1.55 $\mu$m and 2.64 $\mu$m. Intrinsic quality factor at telecom wavelength was shown $(5.4\pm0.4)\cdot10^8$ which is defined by the material losses in ZBLAN. In the mid-IR at 2.64 $\mu$m we demonstrated record quality factor in ZBLAN exceeding $10^8$ which is comparable to the highest values of the Q-factor among all materials in the mid-IR

Platicon Stability in Hot Cavities

The stability of platicons in hot cavities with normal group velocity at the interplay of Kerr and thermal nonlinearities was addressed numerically. The stability analysis was performed for different ranges of pump amplitude, thermal nonlinearity coefficient and thermal relaxation time. It was revealed that for the positive thermal effect, the high-energy wide platicons are stable, while the negative thermal coefficient provides the stability of narrow platicons.Comment: 4 pages, 8 figure

Подход к оценке эффективности человеко-машинного взаимодействия в современных графических оболочках

A system to test multi-window interface efficiency is proposed targeted at evaluating interaction changes introduced in contemporary GUI shells. System includes heart rate monitor and EEG scanner. Set of evaluated parameters, registered by the developed software while providing user with typical tasks to execute, includes speed of execution, error tolerance and intensity of the operator’s work

Genome-Wide Mycobacterium tuberculosis Variation (GMTV) Database: A New Tool for Integrating Sequence Variations and Epidemiology

Background Tuberculosis (TB) poses a worldwide threat due to advancing multidrug-resistant strains and deadly co-infections with Human immunodeficiency virus. Today large amounts of Mycobacterium tuberculosis whole genome sequencing data are being assessed broadly and yet there exists no comprehensive online resource that connects M. tuberculosis genome variants with geographic origin, with drug resistance or with clinical outcome. Description Here we describe a broadly inclusive unifying Genome-wide Mycobacterium tuberculosis Variation (GMTV) database, (http://mtb.dobzhanskycenter.org) that catalogues genome variations of M. tuberculosis strains collected across Russia. GMTV contains a broad spectrum of data derived from different sources and related to M. tuberculosis molecular biology, epidemiology, TB clinical outcome, year and place of isolation, drug resistance profiles and displays the variants across the genome using a dedicated genome browser. GMTV database, which includes 1084 genomes and over 69,000 SNP or Indel variants, can be queried about M. tuberculosis genome variation and putative associations with drug resistance, geographical origin, and clinical stages and outcomes. Conclusions Implementation of GMTV tracks the pattern of changes of M. tuberculosis strains in different geographical areas, facilitates disease gene discoveries associated with drug resistance or different clinical sequelae, and automates comparative genomic analyses among M. tuberculosis strains

Quality of colonoscopy in an emerging country: A prospective, multicentre study in Russia

Background: The quality of colonoscopy has been related to a higher risk of interval cancer, and this issue has been addressed extensively in developed countries. The aim of our study was to explore the main quality indicators of colonoscopy in a large emerging country. Methods: Consecutive patients referred for colonoscopy in 14 centres were prospectively included between July and October 2014. Before colonoscopy, several clinical and demographic variables were collected. Main quality indicators (i.e. caecal intubation rate, (advanced) adenoma detection rate, rate of adequate cleansing and sedation) were collected. Data were analysed at per patient and per centre level (only for those with at least 100 cases). Factors associated with caecal intubation rate and adenoma detection rate were explored at multivariate analysis. Results: A total of 8829 (males: 35%; mean age: 57 + 14 years) patients were included, with 11 centres enrolling at least 100 patients. Screening (including non-alarm symptoms) accounted for 59% (5188/8829) of the indications. Sedation and split preparation were used in 26% (2294/8829) and 25% (2187/8829) of the patients. Caecal intubation was achieved in 7616 patients (86%), and it was ≥85% in 8/11 (73%) centres. Adenoma detection rate was 18% (1550/8829), and it was higher than 20% in five (45%) centres, whilst it was lower than 10% in four (33%) centres. At multivariate analysis, age (OR: 1.020, 95% CI: 1.015–1.024), male sex (OR: 1.2, 95% CI: 1.1–1.3), alarm symptoms (OR: 1.8, 95% CI: 1.7–2), split preparation (OR: 1.4, 95% CI: 1.2–1.6), caecal intubation rate (OR: 1.6, 95% CI: 1.3–1.9) and withdrawal time measurement (OR: 1.2, 95% CI: 1.6–2.1) were predictors of a higher adenoma detection rate, while adequate preparation (OR: 3.4: 95% CI: 2.9–3.9) and sedation (OR: 1.3; 95% CI: 1.1–1.6) were the strongest predictors of caecal intubation rate. Conclusions: According to our study, there is a substantial intercentre variability in the main quality indicators. Overall, the caecal intubation rate appears to be acceptable in most centres, whilst the overall level of adenoma detection appears low, with less than half of the centres being higher than 20%. Educational and quality assurance programs, including higher rates of sedation and split regimen of preparation, may be necessary to increase the key quality indicators

Multi-element PAA calibration with REV method

Phased array antenna (PAA) calibration is the process of determining the PAA channel characteristics; these characteristics are used in beam forming algorithms. In "contactless" PAA calibration methods, measurements are made by a stationary probe antenna placed away from the tested antenna, and the channel characteristics are determined from the measured data. Two of these methods are the MTE and REV methods, based on power only measurements. The MTE and REV calibration methods are described. The special case of the multi-channel antenna (several thousands of elements) is of main interest. A calibration method based on antenna partitioning, channel calibration inside parts, and inter-parts calibration is presented