Mathematical modeling of high-energy materials rheological behavior in 3D printing technology.

In this paper, a mathematical model of the extrusion process in 3D printing of high-energy composites is studied. These composites are formed from polymer binder and powder with bimodal particles obtained by electric explosion technique. The main difficulty of extrusion 3D printing method is primarily linked to the high viscosity of utilized material, especially one with high concentration of particles.

[Surgical treatment of patients with abdominal aortic aneurysm and ischaemic heart disease].

Presented herein are the results of treatment of 137 patients with infrarenal aneurysms of the abdominal portion of the aorta in a combination with ischaemic heart disease. Severity of lesions to the coronary bed and the risk of cardiac complications were assessed according to the SYNTAX score. Depending on severity of angina pectoris and the clinical course of infrarenal aortic aneurysms, we used different tactical approaches to operative treatment of patients.

Thermo-Optical Studies of Laser Ceramics.

A cycle of works on manufacturing and studying laser and magnetooptical ceramics with a focus on their thermo-optical characteristics performed by the research team is analyzed. Original results that have not been published before such as measurements of the Verdet constant in the Zr:TAG, Re:MgAlO, and ZnAlO ceramics are also presented.

High-purity CVD-ZnSe polycrystal as a magneto-active medium for a multikilowatt Faraday isolator.

Prospects for using ZnSe polycrystals synthesized by the chemical vapor deposition (CVD) method for the development of Faraday isolators for high-power radiation at a wavelength of 1076 nm are investigated. A Faraday isolator was built by a conventional scheme for room temperature operation. No thermally induced depolarization was observed in the device for the laser power range up to 1270 W, which is the main limiting factor for powerful isolators.

Enzymatic degradation of the polymer capsules with a hydrophobic core in the presence of Langmuir lipid monolayer as a model of the cellular membrane.

Submicrocapsules were prepared from diethylaminoethyl dextran (DEAE-D), xanthan gum (XG) and bovine serum albumin (BSA) on oil cores by ultrasonic treatment. These capsules were modified with poly-L-lysine (PLL) via electrostatic adsorption. The behavior of the capsules was investigated at an air-water interface after their introduction into an aqueous subphase.

High-power Faraday isolator on a uniaxial CeF crystal.

We have created the first high-power Faraday isolator on an anisotropic magneto-optical element (MOE). The isolator is based on one MOE of a uniaxial CeF crystal and ensures an isolation degree of 30 dB at a high average laser radiation power of 700 W. The limitations due to the anisotropic nature of the crystal do not impose significantly more stringent requirements, either for the beam or the MOE.

Cryogenically cooled CeF3 crystal as media for high-power magneto-optical devices.

The thermally induced depolarization and Verdet constant of CeF crystals-their most important characteristics-have been studied in the 79-293 K temperature range. It has been found that thermal effects reduce substantially upon cooling down to 79 K and the Verdet constant grows in inverse proportion to the temperature. It was shown that CeF crystals are not inferior to TGG as a medium for Faraday isolators, including cryogenic ones.

Integration of bow-tie plasmonic nano-antennas on tapered fibers.

In this article, a new and flexible approach to control the electric field enhancement of bow-tie nano-antennas by integrating them on the lateral of a tapered optical fiber is proposed. The device is driven by a Q-switched laser and the performance of a fabricated nano-antenna in a quartz slide is tested by a Surface Enhanced Raman Scattering (SERS) experiment. A refractive index sensing experiment is also performed and a sensitivity of (240 ± 30) nm/RIU is found in the 1.

Faraday rotator based on TSAG crystal with <001> orientation.

A Faraday isolator (FI) for high-power lasers with kilowatt-level average power and 1-µm wavelength was demonstrated using a terbium scandium aluminum garnet (TSAG) with its crystal axis aligned in the <001> direction. Furthermore, no compensation scheme for thermally induced depolarization in a magnetic field was used. An isolation ratio of 35.

Thick multilayered (silica/gold) dipole nano-antenna.

Nano-antennas are the optical equivalent of antennas that are used to transmit and receive information at radio frequencies. These antennas have been used in different applications in photonics such as optical imaging, particle manipulation, bio-sensing, and improvement of the performance of solar cells. In this article we study composite nano-antennas made of alternating layers of silica and gold.

Investigation of thermo-optical characteristics of magneto-active crystal Na(0.37)Tb(0.63)F(2.26).

Thermo-optical characteristics of a new magneto-active material, Na(0.37)Tb(0.63)F(2.

Large-aperture Faraday isolator based on a terbium gallium garnet crystal.

Unique Faraday isolator based on a TGG single crystal with aperture diameter of 40 mm for high average power lasers has been fabricated and investigated experimentally. The device provides a stable isolation ratio over 30 dB for large-radius laser beams with kilowatt average power radiation typical for high-power applications.

Faraday isolator based on TSAG crystal for high power lasers.

A Faraday isolator based on a new magneto-optical medium, TSAG (terbium scandium aluminum garnet) crystal, has been constructed and investigated experimentally. The device provides an isolation ratio of more than 30 dB at 500 W laser power. It is shown that this medium can be used in Faraday isolators for kilowatt-level laser powers.

Compensation of polarization distortions in Faraday isolators by means of magnetic field inhomogeneity.

We propose a new type of Faraday isolator with compensation of the azimuthally symmetric component of polarization distortions by means of magnetic field inhomogeneity. The depolarization was attenuated in experiments by a factor of 7.

Composite chromium and graphene oxide as saturable absorber in ytterbium-doped Q-switched fiber lasers.

In recent years, graphene and its compounds (e.g., oxides) have been used as saturable absorbers in passive Q-switched and mode-locked lasers, leading to the fabrication of compact pulsed fiber lasers.

Functional electrostimulation of muscles as a method for restoring motor functions.

The main functions of a method of functional electrical stimulation of muscles (FES) are described: diagnostic, prognostic, and therapeutic. The main indication for using the FES method is a deficiency of muscle function, which may be organic (due to lesions to neuromuscular structures) or functional (associated with relaxation of the muscular apparatus). The five most significant functions of the FES method were established: 1) identification of correctable movements and stimulable muscles; 2) identification of the amplitude and time program for stimulation; 3) stimulation regimes for pathological gaits; 4) stimulation parameters; 5) positioning of skin electrodes on the human body.

[Functional myoelectrostimulation as a method for motor functions rehabilitation].

The main features, namely diagnostic, prognostic, therapeutic, of functional myoelectrostimulation (FMES) method are described. FMES is primarily indicated in muscle function deficit, which can be organic (neuromuscle disorders) and functional (muscle relaxation). Five most essential FMES operations include: (1) choice of correctable movements and stimulated muscles; determination of (2) amplitude and temporal stimulation programs; (3) stimulation regimes in pathological gait; (4) stimulation parameters; (5) localization of the skin electrodes on the body.

Photosensitization of singlet oxygen formation by pterins and flavins. Time-resolved studies of oxygen phosphorescence under laser excitation.

To elucidate the biochemical roles of singlet molecular oxygen (1(O2)) in the light-dependent reactions photosensitized by biological blue-light photoreceptors, time-resolved measurements of photosensitized 1O2 phosphorescence (1270 nm) were performed in air-saturated aqueous ((D2)O) solutions of pterins (2-amino-4-hydroxy-6,7-dimethylpteridine (DMP) and 2-amino-4-hydroxy-6-tetrahydroxybutyl-(D-arabo)pteridine (TOP)) and flavins (riboflavin and flavin mononucleotide (FMN)) under excitation with nitrogen laser (337.1 nm) pulses. The 1(O2) quantum yields were found to be 0.

[Parasternal lymphoscintigraphy in planning the radiation therapy of breast cancer].

Altogether 82 breast cancer patients were investigated to determine a possibility of the use of parasternal lymphoscintigraphy with colloid finely divided radiopharmaceuticals 99mTc and 198Au to form individual irradiation fields; 43 patients with fibroadenomatosis were taken as controls. Variants of the localization of parasternal lymph nodes were defined, standard and "optimum" (individual) parasternal irradiation field values were compared. 54.

[The importance of lymphoscintigraphy in breast cancer].

The comparison of results of axillary lymphoscintigraphy with those of morphological examination of surgically removed lymph nodes in 78 patients with breast cancer showed overall reliability of the method to be 0.72, specificity--0.56 and sensitivity--0.