The main principles of operation and design features of a wideband receiving system developed at the Institute of Applied Astronomy, Russian Academy of Sciences, are described. This system operates ...on orthogonal linear polarizations in the 3–16 GHz band with an output-frequency bandwidth of 2 GHz. The results of measurements of the parameters of the receiving system and the characteristics of the RT-13 radio telescope equipped with the receiving system developed are presented.
The features of the transformation of andesites of the East Pauzhetka thermal field under the influence of the argillization process are studied based on a number of samples with different degrees of ...alteration, which were taken from boreholes and outcrops near the study object. The main patterns of changes in the composition and physical and mechanical properties of andesites have been revealed. A schematic diagram of the structure of the thermal field in section has been compiled; this diagram distinguishes three horizons from bottom to top, showing an increase in the degree of hydrothermal transformation: altered andesites, metasomatic breccias, and hydrothermal clays.
Synchrotron radiation incident on a block of multilayer X-ray mirrors of a two-mirror monochromator heats a silicon substrate, which leads to thermal deformation and an increase in the angular error ...of the surface shape. The work examines the heating of a block of multilayer X-ray mirrors by a synchrotron beam with a power of up to 200 W with an energy in the range of 8–36 keV at grazing angles of incidence in the range of 0.5°–1.3°. Using SolidWorks software, the silicon-substrate parameters for mirrors with grooves on the end surface are calculated at which the root-mean-square deviation of the angular error of the substrate’s surface shape is about 1 μrad for a grazing angle of 1.3°, and for smaller angles it is less than 1 μrad. Heat is removed from the substrate surface by water using copper radiators. Reducing the beam aperture at the monochromator output makes it possible to obtain rays reflected from the surface of mirrors, which has a standard deviation of the surface shape of an order of 0.5 μrad, while maintaining 88% of the initial beam power at a grazing angle of 1.3°. The use of a piezoelectric actuator to correct the substrate’s surface shape makes it possible to reduce the root-mean-square shape error to 0.1 μrad and 0.05 μrad at grazing angles of 0.9° and 0.5°, respectively.
A combination of chondroitin and glucosamine is widely used in clinical practice as both a symptomatic and structure-modifying agent for the treatment of osteoarthritis (OA). The emergence of new ...drugs based on this combination substantially expands treatment options for OA therapy.
Objective
: to evaluate the efficacy and safety of Artroflex® that is a combination of chondroitin sulfate 400 mg and glucosamine sulfate 500 mg (CS + GS) to support joint health in patients with knee and/or hip OA.
Patients and methods
. When implementing an open observational research program, the results of using the CS + GS complex were assessed in 644 OA patients (74.7% women) (mean age, 58.0±14.6 years) who experienced moderate/severe pain and required to continuously take non-steroidal anti-inflammatory drugs (NSAIDs). The CS + GS complex was prescribed in a dose of 2 capsules per day for 3 months. The investigators estimated changes in pain on movement by a 0 to 10 verbal pain scale, general health (GH) by a 0–10 visual analogue scale), the Lequesne index, the need for NSAIDs, and patient satisfaction with treatment and its tolerance.
Results and discussion
. After 3-month therapy, there were decreases in pain intensity by 49.2±16.8%, GH scores by 45.6±18.1%, the Lequesne index from 9.0 6.0; 13.0 to 5.0 3.0; 9.0; less than half (45.2%) of the patients still needed for NSAIDs. 82.2% of patients were satisfied or completely satisfied with treatment results; 89.6% reported good treatment tolerance.Adverse events (apparently associated with NSAID use) were recorded in 2.2% of cases. There were no serious complications that required CS + GS treatment discontinuation or hospitalization.
Conclusion
. The findings have indicated that Artroflex® used to support joint health is an effective agent that controls OA symptoms and has a good safety level.
A brief description of the concept of a soft X-ray microscope for the Nanoscope station, which is planned to be installed at the SKIF fourth-generation synchrotron, is given. The microscope is ...designed to study the structure of cells and dynamic processes in them with nanometer spatial resolution. It will use a unique absorption contrast of ~15 between carbon-containing structures and water in the spectral range of the water window, λ = 2.3–4.3 nm, which eliminates the need for contrasting and the use of fluorophores and minimizes the doses of ionizing radiation absorbed in the samples to obtain high-quality 3D images. The scanning and projection schemes of the microscope, their main technical characteristics, including the calculated spectra and parameters of the undulator source are presented, and an estimate of the absorbed doses depending on the resolution is obtained. The main advantage of the proposed concept lies in the use of an objective lens of high-aperture multilayer X-ray mirrors, which makes it possible to clearly visualize the focal section of the sample. Technically simple axial tomography will also be used to reconstruct the three-dimensional structure of frozen or dried samples. In the scanning scheme, due to a low dose of radiation, it will be possible to study living plant cells with a resolution of up to 10 nm, animals with a resolution of up to 80 nm, and cryofixed samples with a resolution of up to 5 nm. In the projection scheme, due to simultaneous observation of the entire focal
XY
section, the time for obtaining three-dimensional images is significantly reduced, but due to a large dose, it will be oriented mainly on the study of fixed samples.
High-power 1.5 - 1.6-μm semiconductor lasers with an asymmetric periodic optically coupled waveguide are developed and their current - voltage, light - current, and spectral characteristics are ...experimentally studied. The characteristics of these lasers are compared with the characteristics of traditional lasers based on double separate-confinement heterostructures. It is shown that the developed lasers have lower divergence and almost the same threshold and power characteristics as conventional lasers with Fabry - Perot resonators. The developed lasers with a cavity length of 1.6 mm and a mesa-stripe contact width of 3 μm mounted in a housing 11 mm in diameter have a power no lower than 200 mW at a pump current not exceeding 700 mA with a divergence of 25 - 35° versus 45° typical for conventional lasers.
We present the conceptual design of a universal materials-research beamline based on the undulator of a fourth-generation synchrotron-radiation source. The distinctive feature of the beamline is its ...capability to work with both spectrally narrow (Δ
E
/
E
~ 10
–4
) and relatively broad, high-intensity radiation beams (5 × 10
–2
). The optical scheme enables rapid switching between diffraction, radiographic, and spectroscopic experimental methods while keeping the beam’s position fixed on the test sample and varying the spot size of the radiation from 100 nm to 1 mm.
High-power semiconductor laser systems based on 1.5 - 1.6 μm single-frequency distributed feedback (DFB) lasers with a sidewall Bragg diffraction grating are developed and their current - voltage, ...light - current, and spectral characteristics are experimentally studied. The characteristics of conventional lasers with a Fabry - Perot cavity and DFB lasers fabricated from one and the same heterostructure are compared. At a pump current not exceeding 700 mA, a conventional laser with a cavity length of 1.6 mm and a mesa-stripe width of 3 μm emits a power no lower than 200 mW versus 150 mW of the DFB laser; both lasers are mounted in a housing 11 mm in diameter. The DFB laser mounted in a butterfly housing emits a power no lower than 100 mW at the exit of the single-mode cable at a pump current not exceeding 500 mA, which, at a 60 % coupling efficiency, corresponds to a power no lower than 165 mW; the side-mode suppression ratio in this case is no lower than 53 dB. It is shown that the wavelength deviation with changing pump current and temperature is almost an order of magnitude lower for the DFB laser than for the conventional laser.
Diagnosis of heart failure with preserved ejection fraction (HFpEF) is associated with certain difficulties since many patients with HFpEF have a slight left ventricular diastolic dysfunction and ...normal filling pressure at rest. Diagnosis of HFpEF is improved by using diastolic transthoracic stress-echocardiography with dosed exercise (or diastolic stress test), which allows detection of increased filling pressure during the exercise. The present expert consensus explains the requirement for using the diastolic stress test in diagnosing HFpEF from clinical and pathophysiological standpoints; defines indications for the test with a description of its methodological aspects; and addresses issues of using the test in special patient groups.
The article is devoted to the analysis of the current status of nuclear cardiology in the Russian Federation. The data on the number of facilities performing radionuclide investigations for the ...diagnosis and monitoring of the treatment of cardiovascular diseases, their staffing and equipment are given. The statistics of the conducted nuclear cardiology tests for 2018-2020 are given, as well as their methods, features and diagnostic significance are described.
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