Twisted Few-Mode Optical Fiber with Improved Height of Quasi-Step Refractive Index Profile.

This work presents designed and fabricated silica few-mode optical fiber (FMF) with induced twisting 10 and 66 revolutions per meter, core diameter 11 µm, typical "telecommunication" cladding diameter 125 µm, improved height of quasi-step refractive index profile and numerical aperture 0.22. Proposed FMF supports 4 guided modes over "C"-band.

Gain of electron orbital angular momentum in a direct laser acceleration process.

Three-dimensional "particle in cell" simulations show that a quasistatic magnetic field can be generated in a plasma irradiated by a linearly polarized Laguerre-Gauss beam with a nonzero orbital angular momentum (OAM). Perturbative analysis of the electron dynamics in the low intensity limit and detailed numerical analysis predict a laser to electrons OAM transfer. Plasma electrons gain angular velocity thanks to the dephasing process induced by the combined action of the ponderomotive force and the laser induced-radial oscillation.

Author Correction: 137 ancient human genomes from across the Eurasian steppes.

with In this Article, Angela M. Taravella and Melissa A. Wilson Sayres have been added to the author list (associated with: School of Life Sciences, Center for Evolution and Medicine, The Biodesign Institute, Arizona State University, Tempe, AZ, USA).

137 ancient human genomes from across the Eurasian steppes.

For thousands of years the Eurasian steppes have been a centre of human migrations and cultural change. Here we sequence the genomes of 137 ancient humans (about 1× average coverage), covering a period of 4,000 years, to understand the population history of the Eurasian steppes after the Bronze Age migrations. We find that the genetics of the Scythian groups that dominated the Eurasian steppes throughout the Iron Age were highly structured, with diverse origins comprising Late Bronze Age herders, European farmers and southern Siberian hunter-gatherers.

Testing different classification methods in airborne hyperspectral imagery processing.

To enhance the efficiency of machine-learning algorithms of optical remote sensing imagery processing, optimization techniques are evolved of the land surface objects pattern recognition. Different methods of supervised classification are considered for these purposes, including the metrical classifier operating with Euclidean distance between any points of the multi-dimensional feature space given by registered spectra, the K-nearest neighbors classifier based on a majority vote for neighboring pixels of the recognized objects, the Bayesian classifier of statistical decision making, the Support Vector Machine classifier dealing with stable solutions of the mini-max optimization problem and their different modifications. We describe the related techniques applied for selected test regions to compare the listed classifiers.

Improved technique for retrieval of forest parameters from hyperspectral remote sensing data.

This paper describes an approach of machine-learning pattern recognition procedures for the land surface objects using their spectral and textural features on remotely sensed hyperspectral images together with the biological parameters retrieval for the recognized classes of forests. Modified Bayesian classifier is used to improve the related procedures in spatial and spectral domains. Direct and inverse problems of atmospheric optics are solved based on modeling results of the projective cover and density of the forest canopy for the selected classes of forests of different species and ages.

[Nitric oxide and electrogenic metals (Ca, Na, K) in epidermal cells].

Using atomic emission spectrometry and EPR analysis metal-ligand homeostasis (MLH) has been studied in epidermal cells of 954 liquidators of the Chernobyl accident and 947 healthy individuals. A possible association of the redox status with the quantitative changes in the MLH, which could be used as discriminators of oxidative/nitrosative stress, attracts special interest. Characteristic features of oxidative stress mainly related to electrogenic metals (Ca, K, Na), were found not only among the liquidators examined, but also in some healthy individuals (18.

Retrieval of forest stand attributes using optical airborne remote sensing data.

Optical remote sensing data processing is proposed for the airborne images of high spectral and spatial resolution. Optimization techniques are undertaken to gain information about spatial distribution of the pixels on the hyperspectral images and the texture of the forest stands of different species and ages together with reducing redundancy of the spectral channels used. The category of neighborhood of pixels for particular forest classes and the step up method of selecting optimal spectral channels are employed in the relevant processing procedures.

Parameterization of volume scattering function of coastal waters based on the statistical approach.

A parameterization of the volume scattering function (VSF) specific to coastal waters is proposed. We have found that the standard VSF parameterizations proposed by Fournier-Forand and Petzold do not fit our measurements obtained with a high angular resolution VSF-meter for water samples taken in the Black Sea coastal zone. We propose modeling VSF as a linear function of scattering, backscattering and particulate absorption.

Parameterization of light absorption by components of seawater in optically complex coastal waters of the Crimea Peninsula (Black Sea).

The absorption of sunlight by oceanic constituents significantly contributes to the spectral distribution of the water-leaving radiance. Here it is shown that current parameterizations of absorption coefficients do not apply to the optically complex waters of the Crimea Peninsula. Based on in situ measurements, parameterizations of phytoplankton, nonalgal, and total particulate absorption coefficients are proposed.

[Expert work during technogenic extreme situations (Report II)].

The article is devoted to the organizational principles of work of expert institutions and its subdivisions with reference to technogenic catastrophes with mass victims. The problems of interactions of representatives from different structures and departments made busy with the work at the place of event are discussed in terms of forensic medicine. Special attention is paid to the problems of expert institution readiness for work under conditions of extreme situations depending on the medical-and-tactical characteristics of damage focus.

[Repeated surgeries on the thyroid gland in nodular euthyroid goiter].

Medical histories of 214 patients hospitalized with diagnosis "recurrent nodular goiter" were studied retrospectively. Complex clinical, laboratory and instrumental examination was carried out in all the patients. Comparative analysis demonstrated that in the structure of recurrent goiter nodular colloid form dominated (84.

[Expert work during technogenc emergency situations (Report I)].

The authors discuss the organizational principles of the work of expert institution and its subdivisions with reference to technogenic catastrophes accompanied with mass human victims. The problems of interaction of the representatives from different structures and departments taking part in the work at the place of event are considered in terms of forensic medicine. The attention is concentrated on the problems of expert institution readiness to work under conditions of extreme situations depending on the medicotactical characteristics of defeat focus.

[Comparative evaluation of effects of various bronchodilators in sarcoidosis].

The investigation was undertaken to compare three bronchodilators on patients with respiratory sarcoidosis. Ninety patients (66 females and 24 males) with intrathoracic sarcoidosis were examined. X-ray stages I, II, III, and IV were seen in 48.

[Effects of ultraviolet irradiation on structural and functional condition of T- and B-lymphocytes of human blood].

The influence of ultraviolet (UV) radiation on structural and functional condition of membranes T- and B-lymphocytes of human blood is investigated. It is shown, that intergral flow of UV-light (240-390 nm) in doses 151-1359 J/m2 leads to the increase of the expression of some HLA-antigen (DR1, DR2, DR5, DR7) and Fc-receptors on membranes of B-lymphocytes. The level of HLA-antigen was increased by 20-500% from the initial state after exposure to different doses.

[Comparison of flow-volume curve parameters in patients with respiratory sarcoidosis and chronic non-specific pulmonary diseases].

62 patients with respiratory sarcoidosis (RS) and 50 patients with chronic nonspecific pulmonary diseases (CNSPD) inhaled 1 ml (250 mg ipratronium bromide and 500 mcg phenoterol hydrobromide) berodual by means of nebulizer. 68% of the examinees responded with obstruction of the distal part of the respiratory tree. RS causes partially reversible defects in permeability, primarily at the level of small bronchi.

[The state legal and expert identification aspects of protecting the right of the person for citizens of the Russian Federation].

The article deals with the questions concerning the problem of person identification, different extreme situations. This problem is closely connected with ensuring of national security of Russia. The authors give the definition of person's right in contact with constant threat to violate this right.

Thoracoscopic surgery in the management of mediastinal masses. Indications, complications, limitations.

Background: In recent times thoracoscopy has been used for diagnoses and treatment of mediastinal masses. This study is a preliminary review of indications, complications, and limitations in this field of surgery.

Methods: Twenty-eight patients with mediastinal masses were operated in the Clinical Oncological Centre, Kazan.

[Around the Semipalatinsk proving grounds: the radioecological situation and the population radiation doses in Semipalatinsk Province (based on data from the report of the Interdepartmental Commission)].

The paper represents some results of a joint commission, organized by the USSR Ministry of Health by order of the USSR Council of Ministers at public requests. The commission worked in the area neighbouring the proving ground at Semipalatinsk in the period of May-July 1988. A radiological situation there was investigated after underground nuclear testing on July 8, 1989.