208 research outputs found

    Направление администрации Института

    Get PDF
    Aim. To study serum content of a number of known adipokines, myokines and cytokines and compare obtained data with overweight phenotype and characteristics of tumor in untreated patients with endometrial cancer (EC) Materials and methods. The study included 88 patients with a mean age 60.08±0.67 years and a mean body mass index (BMI) 32.90±0.83. Patients were subjected to anthropometry and analysis of laboratory parameters, including serum level of leptin, adiponectin, omentin, prefilin (Pref-1), myostatin, irisin, IL-6 as well as insulinemia and insulin resistance index (HOMA-IR). On the basis of combination of anthropometric and laboratory data patients with overweight (BMI >25.0) were subdivided into the groups with "standard" (S) and conditionally "metabolically healthy" (MH) phenotype. Results. Levels of leptin, insulin and adiponectin in the serum of patients with EC are associated with BMI value and demonstrate significant differences between S and MH groups. Levels of prefilin, myostatin, and IL-6 are not associated with an increase in BMI, but are also different in patients with S and MH phenotype of overweight.For levels oа irisin, omentin, and TNF-alphathere is no peculiar dependence both, the BMI, and of belonging to a group with S or MH phenotype. Omentin level in the serum is associated with less favorable tumor differentiation (MH group), while IL-6 level – with a more advanced stage of the tumor (all patients and group S). Conclusion. Adipokines, myokines and cytokines circulating in blood of EC patients vary in their connections with BMI or with "standard" or "metabolically healthy" phenotype of its excess. They vary also in relation to EC features, which in sum may have practical importance

    Soliton Squeezing in a Mach-Zehnder Fiber Interferometer

    Get PDF
    A new scheme for generating amplitude squeezed light by means of soliton self-phase modulation is experimentally demonstrated. By injecting 180-fs pulses into an equivalent Mach-Zehnder fiber interferometer, a maximum noise reduction of 4.4±0.34.4 \pm 0.3 dB is obtained (6.3±0.66.3 \pm 0.6 dB when corrected for losses). The dependence of noise reduction on the interferometer splitting ratio and fiber length is studied in detail.Comment: 5 pages, 4 figure

    Ultrasound of Acute Appendicitis in the Admission Room of a Multidisciplinary Surgical Hospital

    Get PDF
    Ultrasound (US) for diagnosing acute appendicitis (AA) and its complications in the admission room may be used as a primary diagnostic method in urgent patients. A total of 180 adult patients underwent US for suspected appendicitis; these results showed high possibilities in pathology screening and differential diagnosis from similar clinical diseases. The accuracy of US in detecting AA with obvious clinical findings and typical position is 100%, but in retrocecal and retroperitoneal forms, it decreases to 84%. With our algorithm of the right iliac and localized pain regions, US scanning optimizes the screening of patients with suspected AA presented in the admission room

    The Imaging of Legg-Calve-Perthes Disease

    Get PDF
    Diagnosis of hip joint pathology remains a serious problem in childhood and adolescence. A wide range of pathologies—including dysplastic, dystrophic, inflammatory, oncological and post-traumatic diseases of the musculoskeletal system—leads to the advancement of imaging methods and techniques. Legg-Calve-Perthes disease (LCPD) is a common cause of hip pain in children that may be initially clinically and radiographically difficult to diagnose Radiography of the pelvis in two views (anteroposterior and Lauenstein) is the main method of diagnosing aseptic necrosis. Destructive changes of the femoral head and neck of the femur are clearly determined. However, the presence of X-ray negative patterns at the first stage of the disease and the impossibility of visualizing all the anatomical structures induce us to improve the diagnostic algorithm of this difficult pathological process

    X-ray Polarization Observations of BL Lacertae

    Get PDF
    Blazars are a class of jet-dominated active galactic nuclei with a typical double-humped spectral energy distribution. It is of common consensus the Synchrotron emission to be responsible for the low frequency peak, while the origin of the high frequency hump is still debated. The analysis of X-rays and their polarization can provide a valuable tool to understand the physical mechanisms responsible for the origin of high-energy emission of blazars. We report the first observations of BL Lacertae performed with the Imaging X-ray Polarimetry Explorer ({IXPE}), from which an upper limit to the polarization degree ΠX<\Pi_X<12.6\% was found in the 2-8 keV band. We contemporaneously measured the polarization in radio, infrared, and optical wavelengths. Our multiwavelength polarization analysis disfavors a significant contribution of proton synchrotron radiation to the X-ray emission at these epochs. Instead, it supports a leptonic origin for the X-ray emission in BL Lac.Comment: 17 pages, 5 figures, accepted for publication in ApJ

    Discovery of X-ray polarization angle rotation in active galaxy Mrk 421

    Full text link
    The magnetic field conditions in astrophysical relativistic jets can be probed by multiwavelength polarimetry, which has been recently extended to X-rays. For example, one can track how the magnetic field changes in the flow of the radiating particles by observing rotations of the electric vector position angle Ψ\Psi. Here we report the discovery of a Ψx\Psi_{\mathrm x} rotation in the X-ray band in the blazar Mrk 421 at an average flux state. Across the 5 days of Imaging X-ray Polarimetry Explorer (IXPE) observations of 4-6 and 7-9 June 2022, Ψx\Psi_{\mathrm x} rotated in total by 360\geq360^\circ. Over the two respective date ranges, we find constant, within uncertainties, rotation rates (80±980 \pm 9 and 91±8/day91 \pm 8 ^\circ/\rm day) and polarization degrees (Πx=10%±1%\Pi_{\mathrm x}=10\%\pm1\%). Simulations of a random walk of the polarization vector indicate that it is unlikely that such rotation(s) are produced by a stochastic process. The X-ray emitting site does not completely overlap the radio/infrared/optical emission sites, as no similar rotation of Ψ\Psi was observed in quasi-simultaneous data at longer wavelengths. We propose that the observed rotation was caused by a helical magnetic structure in the jet, illuminated in the X-rays by a localized shock propagating along this helix. The optically emitting region likely lies in a sheath surrounding an inner spine where the X-ray radiation is released

    Studying the Influence of Moisture Content in Grain on the Efficiency of the Microwave Field Transfer into a Grain Layer with the Use of a Computer Model

    No full text
    The objective of these studies was to determine the dependence of the distribution of the microwave field into a grain layer and the efficiency of energy transfer from the magnetron into the grain layer, via a waveguide, on the moisture content. The subject of the research was a semicircular waveguide with slot radiators that supply a microwave field to the grain surrounding the waveguide. The change in the directional diagram of the microwave field in the longitudinal direction of the waveguide was studied using CST Microwave Studio 2019 software. It was found that the change in the moisture content of the processed grain leads to a significant change in both the radiation and total efficiency values of the waveguide. For instance, the radiation efficiency of the waveguide decreases by 15.1% (from 68.729 dB to 58.294 dB) when the moisture content of the processed grain increases from 14% to 26%. The total radiation efficiency also decreases (from 11.27 dB to 21.7 dB). In this case, not only the value of the radiation efficiency but also the shape of its dependence on the magnetron radiation frequency change. The results of this study enable the formulation of a requirement for a selective approach to the alignment of emitting waveguides depending on the moisture content of the processed grain. Data were obtained on the change in the Q-factor for resonators in which grain layers are processed, depending on the variation in grain moisture content. The research results suggest that when designing microwave convective zones for grain processing, the quality factor of the resonator should not be considered as the primary parameter. The main focus should be on maximizing the radiation efficiency of the waveguides

    Using Modeling to Select the Type of Microwave Field Emitter for Dense-Layer Grain Dryers

    No full text
    The microwave field is used for drying and disinfecting grains during the pre-sowing seed treatment. The use of a microwave field in these installations leads to an increase in their productivity and a decrease in the energy consumed by them. In grain dryers, where the grain moves in a dense layer without being loosened, one of the challenges in using microwave fields is ensuring sufficient uniformity of the field distribution. In this article, waveguide design options that introduce microwave radiation into the grain layer are discussed. The objective of this study was to use application software to find the optimum type of transmitter from the three options presented. A mathematical simulation of the electromagnetic field distribution was performed with the use of CST Microwave Studio software 2019 in order to evaluate and compare horn-type, rectangular, and semicircular waveguides. The data on the standing wave ratio and radiation efficiency of these types of waveguides have been reported. The specific features of the microwave electromagnetic field distribution and radiation power in the output of these waveguides have been described. The results of mathematical simulations revealed that semicircular waveguides with slot-type radiators are preferable for processing dense grain layers

    Dynamic Arches Destruction by a Bulk Material Flow Separator: A Case Study of the Separator Usage in Microwave Grain Processing Plants

    No full text
    Hoppers for unloading bulk materials are an indispensable feature of many technological machines and not only those employed in agricultural production. One of the problems in the operation of hoppers is the appearance of dynamic arches which make the outflow of grain uneven. Experimental studies have previously shown that the formation of dynamic arches creates an uneven outflow of grain along the vertical zones of outlet hoppers. This can lead to the processing mode violation of bulk material and loss of machine productivity. This paper theoretically shows that the use of arch-breaking devices with an element oscillating in the grain layer requires systems for automatic adjustment of oscillation frequency. This complicates the design and makes it more expensive. It is proposed to amend the type of material outflow as it moves along the hopper’s height to solve this problem. The possibility of employing this approach has been tested on the use of a bulk material flow separator in the outlet hopper. The bulk material flow separator is made in a plate form and is installed rigidly between two opposite walls of the outlet hopper. Thus, the volume of the hopper is divided into two vertical equal parts. With the help of experimental studies, it was determined that the lower side of the bulk material flow separator should be at a distance of 0.3 of the total hopper height from the discharge opening, while the upper side of the separator should be at a distance of 0.25 of the hopper’s height from the top edge of the hopper. The experimental verification of flow separator use confirmed its effectiveness
    corecore