Affine diffractive beam dividers.

Diffractive optical elements that divide an input beam into a set of replicas are used in many optical applications ranging from image processing to communications. Their design requires time-consuming optimization processes, which, for a given number of generated beams, are to be separately treated for one-dimensional and two-dimensional cases because the corresponding optimal efficiencies may be different. After generalizing their Fourier treatment, we prove that, once a particular divider has been designed, its transmission function can be used to generate numberless other dividers through affine transforms that preserve the efficiency of the original element without requiring any further optimization.

Three-dimensional polarization of fields radiated by partially coherent electromagnetic cylindrical sources.

Partially coherent electromagnetic sources with cylindrical symmetry and infinite extent radiating outward are introduced. Their 3 × 3 cross-spectral density matrix is given through expansions of the field components in terms of basis functions related to the Hankel functions. The spectral density and the three-dimensional degree of polarization of such sources and the fields they radiate are examined. Several examples are presented and discussed. Among them, a class of cylindrical sources whose coherent vector modes coincide with the above basis functions is defined and studied.

Partially coherent spherical sources with spherical harmonic modes.

A class of partially coherent spherical sources is introduced whose cross-spectral density across the surface has a modal expansion made up of spherical harmonics. For such sources, the solution of the propagation problem in all the outer spaces can be written through a series of the propagated modes, which maintains the spherical harmonic structure. The main features of this class of cross-spectral densities are derived illustrating their coherence properties with examples. Attention is paid to the properties of radial coherence. In particular, it is clearly shown that sources with perfect radial coherence exist with angular coherence that is only partial.

Cylindrical partially coherent scalar sources.

Partially coherent scalar sources with cylindrical symmetry radiating outwards are introduced. Homogeneous cross-spectral densities are shown to possess angularly modulated Hankel modes, whose amplitudes are subject to a filtering process during propagation. Simple criteria for treating such sources are given. For the case of an incoherent cylinder, the number of effective modes is found and spatial coherence is shown to appear in the radiated light. The radial coherence of the radiated field is then examined. Non-homogeneous cylindrical sources are also introduced.

On-axis polarization of beams radiated by electromagnetic circularly coherent sources.

On-axis spectral density and degree of polarization of beams radiated by electromagnetic (EM) sources with circular correlations are shown to be finely controlled by changing the source parameters. We reveal, in particular, that in this beam class, unlike for all previously known stationary beams, it is possible to control independently the dynamics of the on-axis spectral density and the degree of polarization. This was enabled by the obtained analytical expression for the on-axis polarization matrix, derived for general EM sources with circular coherence and Gaussian spectral density across the source plane. A simple experimental scheme for generating a broad class of EM circularly coherent sources is devised involving only a line source, a lens, and a transparency, possibly anisotropic.

Tailoring on-axis spectral density with circularly coherent light beams.

The on-axis cross-spectral density (CSD) of a beam radiated by a stationary source with a circular coherence state and a Gaussian spectral density is obtained in the closed form. It is revealed that the on-axis CSD is expressed via the Laplace transform of the source's degree of coherence or the Hilbert transform of the corresponding pseudo-mode weighting function. Such relations enable efficient tailoring of the on-axis spectral density, as we show with a slew of numerical examples.

On z-coherence of beams radiated by Schell-model sources with Gaussian profile.

The degree of coherence and the intensity distribution on the axis of the beam radiated by a planar partially coherent source of the Schell-model type are investigated. We present an expression for the on-axis cross-spectral density which is valid for a very general Schell-model source, with the only constraint that the intensity distribution across the source is Gaussian. Furthermore, we show that such an expression takes very simple analytical forms for several commonly used degrees of coherence of the source.

On z-coherence in self-focusing.

Both the intensity distribution and the degree of coherence between pairs of points along the propagation axis (z-coherence) are derived in closed form for a phenomenon of self-focusing produced by circularly coherent light. The first confirms results previously obtained numerically, while the second exhibits new complex features. The physical interpretation is obtained by a suitable pseudo-modal expansion that suggests an analogy with a simple two-mode structure.

Propagation of temporal coherence gratings in dispersive medium with a chirper.

In this paper, the propagation of Temporal Coherence Grating (TCG) pulse trains in a dispersive medium with a chirp is investigated for the first time. The two-time mutual coherence function of the TCG pulse trains propagating through extended dispersive medium specified by temporal ABCD matrix is derived and the evolution of their mean intensity and temporal degree of coherence (DOC) is explored. It is shown that the distribution of the mean intensity can be modulated freely by the number of grating lobes N, grating constant a, pulse duration T0, power distributions vn, group-velocity dispersion coefficient ß2 and the medium chirper s. Upon dispersive-medium propagation, the single pulse splits into N+1 subpulses with the same or different peak intensities which depend on power distributions vn. What's more, during the propagation the pulse self-focusing occurs being the chirp-induced non-linear phenomenon. And the distribution of temporal DOC will degenerate into Gaussian form from initial periodic coherence distribution with increasing propagation distance z or adjusting incident pulse parameters and medium dispersion. The physical explanation and numerical illustrations relating to the pulse behavior are included.

Mueller matrix of the particle-free atmospheric enhanced backscatter.

The spatially resolved Mueller matrix of a mono-static optical system with the corner-cube retro-reflector operating in the presence of clear-air atmospheric turbulence is measured for the first time, to the best of our knowledge. The changes in the polarization properties of the beam are caused by the combination of deterministic polarimetric modulation by the retro-reflector and random scalar modulation of the return beam by atmospheric turbulence. In particular, the spatial structure of the Mueller matrix within the enhanced backscatter area is revealed.

Tumor-Infiltrating Lymphocytes in Breast Cancer. Association with Clinical and Pathological Parameters.

In patients with primary resectable breast cancer, a positive correlation between the age and the count of CD16+ lymphocytes and a negative correlation of this parameter with the number of regulatory CD4+CD25+CD127- cells and proliferative activity of Ki-67 tumor cells were revealed. Higher level of Ki-67 was associated with reduced number of effector lymphocytes (CD8+ and CD16+) and elevated content of regulatory CD8+CD11b-CD28- T cells. The absence of expression of estrogen receptors was associated with reduced cytotoxic potential of CD8+ T cell in comparison with ER+ breast cancer. The percentage of CD8+ lymphocytes (CD3+CD8+ and CD8+CD11b+CD28+) among lymphocytes infiltrating the tumor was higher in PR+ breast cancer than in PR- tumors. With increasing the tumor load, the number of lymphocytes expressing CD16 marker and their cytotoxic potential decreased.

Propagation dynamics of partially coherent crescent-like optical beams in free space and turbulent atmosphere.

We introduce theoretically and realize experimentally a class of random, wide-sense stationary optical beams with uniform correlations which, on propagation in free space, produce a crescent-like intensity distribution with the maximum at an off-axis position. The crescent's position of maximum intensity accelerates transversally at intermediate distances, and then exhibits a constant lateral shift further from the axis in the far zone of the source. We also show that on propagation in the isotropic turbulent atmosphere, the crescent beam shifts away from the axis as well, but slower than in free space, with rate depending on the strength of turbulence. These results are of importance for optical systems operating through long-range turbulent channels in which a beam must have a range-dependent tilt, e.g. on travelling around an obstacle.

Flatness parameter influence on scintillation reduction for multi-Gaussian Schell-model beams propagating in turbulent air.

Reduction in the scintillation index of multi-Gaussian Schell-model beams propagating in turbulent air is demonstrated as a function of two source parameters: the r.m.s. coherence width and the summation index. The beams were generated with the help of a nematic phase-only, reflective spatial light modulator at a cycling rate of 333 frames per second and recorded after propagating through a weakly turbulent air channel over a distance of 70 m. Experimental results are in good agreement with theory.

[Novel Enzyme Preparations with High Pectinase and Hemicellulase Activity Based on Penicillium canescens Strains].

Recombinant strains of Penicillium canescens producing homologous pectin lyase A and heterologous endo- 1,5-α-arabinase A and endo- 1,4-α-polygalacturonase, as well as enzymes of the host strain (α-L-arabinofuranosidases, xylanases, and others), were obtained by genetic engineering. The enzyme preparations (EPs) obtained from the cultural medium of recombinant P. canescens strains efficiently hydrolyzed raw plant material with a high content of pectin compounds. It was shown that the yield of reducing sugars and arabinose increased 16 and 22% in comparison with the control EP based on the host strain when one of the obtained EPs was used for beet pulp hydrolysis. It was established that the most active EP consisted of pectin lyase (10%), endo-1,5-arabinase (26%), α-L-arabinofuranosidase and arabinoxylan-arabinofuranohydrolase (12%), and xylanase (10%). The activities of pectin lyase, polygalacturonase, and arabinase of the EP in reactions with various substrates were determined. The specificity, pH and T-optima, and thermal stability of the homogenous recombinant endo- 1,5-α-arabinase were investigated. The kinetic parameters (K(m), K(cat)) of the linear arabinan hydrolysis were determined.

[Use of Endoglucanase IV from Trichoderma reesei to Enhance the Hydrolytic Activity of a Cellulase Complex from the Fungus Penicillium verruculosum].

The effect of polysaccharide monooxygenase (endoglucanase IV) from the fungus Trichoderma reesei on the hydrolysis of polysaccharide substrates by cellulases secreted by the fungus Penicillium verruculosum has been investigated. Supplementation of the enzyme complex from P. verruculosum by endoglucanase IV from T. reesei has been shown to elevate the efficiency of cellulose hydrolysis by 45%.

Hydrogen respiratory test: pilot examinations for evaluation of the small intestinal colonization by normal microflora.

Respiration hydrogen analyzer H2Rate has been used in pilot examinations of a group of students. This method for noninvasive diagnosis of small intestinal diseases promotes proper interpretation of the results. Free hydrogen level in the exhaled air increases as a result of lactulose (diagnostic agent) cleavage by enteric microflora within about 3 h. Based on the experimental data, the main groups with characteristic curves reflecting the time course of hydrogen concentrations have been distinguished. Excessive bacterial colonization of the intestine can correspond to emergence of characteristic peaks of hydrogen concentrations in the curve. Hydrogen concentrations in exhaled air can also be analyzed to evaluate the rate of the substrate propulsion in the middle compartment of the intestine.

Propagation of cross-spectral densities from spherical sources.

We show that the cross-spectral density in the far zone of a homogeneous spherical source can be described as a low-pass filtered version of that existing across the source surface. We prove that, to an excellent approximation, the corresponding filter with respect to a (normalized) spatial frequency ξ has a functional structure of the form √(1-ξ2), for 0≤ξ≤1. The cases of spatially incoherent and Lambertian sources are treated as significant examples.

Application of electrochemical breath test for detection of Helicobacter pylori in screening of Moscow students.

The incidence of Helicobacter pylori infection is analyzed by the results of screening of first- and fourth-year students of Moscow Institute of Foreign Affairs using HelicoSense Scientific breath test system. Age-related dynamics of the infection in patients examined for the first time has been traced. The data on infection rates in patients after eradication therapy are presented.

Sufficient condition for polarization invariance of beams generated by quasi-homogeneous sources.

Conditions for invariance of the degree and the state of polarization of beams radiated by electromagnetic quasi-homogeneous sources into the far-zone are derived. An example is given relating to electromagnetic Bessel-correlated sources.

[Phenotype of immunocompetent cells and its role in antitumour immune response].

The paper contains an overview of the role of certain minor subpopulations of lymphocytes in tumour growth and of the main results obtained in the studies of the phenotype of immunocompetent cells from cancer patients. Special attention is given to selected indicators of immunity as predictors of the disease and efficacy of immunotherapy.