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Room temperature linear arrays (up to 160 detectors in array) from silicon metal- oxide-semiconductor field-effect transistors (Si-MOSFETs) have been designed for sub- THz (radiation frequency 140 GHz) close to real-time direct detection operation scanner to be used for detection and recognition of hidden objects. For this scanner, the optical system with aspherical lenses has been designed and manufactured. To estimate the quality of optical system and its resolution, the system modulation transfer function was applied. The scanner can perform real-time imaging with the spatial resolution better than 5 mm at the radiation frequency 140 GHz and contrast 0.5 for the moving object speed up to 200 mm/s and the depth of field 20 mm. The average dynamic range of real time imaging system with 160-detector linear array is close to 35 dB, when the sources with the output radiation power of 23 mW (IMPATT diodes) are used (scan speed 200 mm/s). For the system with 32-detector array, the dynamic range was about 48 dB and for the single-detector system with raster scanning 80 dB with lock-in amplifier. However, in the latter case for obtaining the image with the sizes 20×40 mm and step of 1 mm, the average scanning time close to 15 min is needed. Convolutional neural network was exploited for automatic detection and recognition of hidden items.

The article identifies the features of the pathology of the gastrointestinal tract in patients with gastroesophageal reflux disease on the background of hypothyroidism. The frequency of gastroesophageal reflux disease and the severity of this disease increase with age and the presence of comorbid pathology. In the elderly, the frequency of the typical esophageal manifestations decreases, and the erosive esophagitis with atypical symptoms is more common. The growing number of cases of combined thyroid dysfunction with gastropathology requires in-depth study of the reasons for the relationship between these processes. Pathological changes in the gastrointestinal tract in these patients make their condition severer, contributing to the development and progression of metabolic disorders. An important aggravating effect on the regulatory mechanisms of esophageal kinetics has a pathological functioning of the thyroid gland on the background of iodine deficiency. Results and discussion. In patients with gastroesophageal reflux disease with hypothyroidism, all changes in gastric and duodenal function are associated with a decrease in the acid-forming function of the gastric mucosa, due to its atrophy, decreased tone and contractility of the stomach. This in turn leads to a slowing of gastric and duodenal evacuation, dysfunction of the closing capacity of the cardia and, as a consequence, the development of duodenogastroesophageal reflux. The esophageal contents are not so pronounced, so patients with non-erosive forms of esophagitis predominate (46.2%) against 16% of patients in the second group (patients with gastroesophageal reflux disease). At the same time, erosive forms predominate among patients in the control group with predominant acid reflux. It should be noted that there is a clear relationship between the frequency of erosive changes in the esophageal mucosa and the duration of the disease. Thus, among patients of the main group with a 5-year history of the disease, the number of erosive forms of gastroesophageal reflux disease was minimal. The number of erosive changes in the esophageal mucosa increased sharply in patients with a 10-year history and reached its maximum after 15 years from the onset of the disease. Conclusion. The delay in gastric evacuation is more pronounced in patients with gastroesophageal reflux disease on the background of hypothyroidism. It can be explained by a decrease in gastric motility and the presence of duodenostasis. The slowing of gastric evacuation was more pronounced in patients with gastroesophageal reflux disease on the background of reduced thyroid function. In patients with gastroesophageal reflux disease on the background of hypothyroidism there is an alkaline duodenogastroesophageal reflux as a consequence of reduced acid-forming function of the gastric mucosa and reduced contractility of the stomach and duodenum

For the treatment of patients with severe multysistem pelvic trauma accompanied by pelvic bleeding, many algorithms have been proposed that have different procedures for the use of various methods of surgical hemostasis, but none of them may guarantee the complete arrest of pelvic bleeding. The purpose of this study was to estimate clinical efficacy and developed algorithm, aimed at timely diagnosis of intrapelvic bleeding and its complete arrest with the help of different methods of surgical hemostasis in patients with severe concomitant injury of the pelvis. The article analyzes the results of treatment of 168 patients with unstable pelvic ring injuries and signs of intrapelvic bleeding, who were treated in two trauma centers of the first level in St. Petersburg: I.I. Dzhanelidze St. Petersburg Research Institute of Emergency Medicine and Military Surgery Clinic of S.M. Kirov Military Medical Academy in 2010-2018. The victims were divided into two statistically homogeneous groups. In the comparison group (75 people), the pelvic ring was mechanically stabilized with the Ganz C-clamp or the anterior part of the pelvis was fixed with an external fixation device (EFD), and the arrest of the ongoing pelvic bleeding was expected due to occur due to the effect of biological tamponade. In the main group (93 people), after mechanical stabilization of the pelvic ring, various methods of surgical hemostasis were used: balloon occlusion of the aorta, pelvic tamponade, angiography with embolization. The choice of method for surgical haemostasis after trauma depended on the severity of the affected condition of hemodynamic parameters, availability of life-threatening consequences of damage to other areas of the body and the efficacy of previously applied method for intrapelvic bleeding arrest. The introduction of modern diagnostic and treatment algorithm, aimed at complete hemostasis in patients with ongoing intrapelvic bleeding reduced the overall mortality rate by 1.7 times, mortality within 24 hours of admission by 2.3 times, as well as the duration and the volume of blood transfusion therapy by 3 and 1.8 times.Authors declare lack of the conflicts of interests.

In recent years, significant progress has been made in the treatment of severe injuries and traumas. In critical situations, for the heaviest category of wounded, the outcome is largely determined in the next few minutes after admission to the hospital. The only possible tactic that gives a chance to save the lives of such victims is the tactics of multi-stage surgical treatment (damage control). The low effectiveness of traditional methods of training surgeons in the basics and techniques of this tactic makes it necessary to develop new forms of training. One of the most progressive and sought-after is training on biological material (large animals or cadaver material), but the methodology for conducting such studies has not been worked out before. For the first time in Russia in November 2018, a unique training and practical course «SMART» (Modern Methods and Algorithms for the Treatment of Wounds and Traumas) was conducted, combining training in both living tissues and cadavers. Participants were given the opportunity to see and independently work out the basic combinations of typical surgical techniques and maneuvers aimed at eliminating the life-threatening consequences of injuries and traumas.

Clinical Center of Stomatology of FMBA of Russia, 123098, Moscow, Russian FederationDental morbidity in childhood is practically not reduced. The effectiveness of preventive measures is great in early childhood, and therefore relevant research on the epidemiology of the prevalence and intensity of caries and gingivitis in children 6-9 years. Surveyed 176 people at the school of Moscow and the indicators of dental disease and treatment needs among schoolchildren 6 to 9 years. In Moscow, the prevalence of caries - 92,0%, periodontal disease - 19,3% with intensity of 1,67±0,03 (CPU) and 0,53±0,03 (CPI), respectively, with satisfactory and good oral hygiene in 81,1% of the surveyed children is high in the period of a change bite. The need for dental treatment in the examined patients has a structure: in the treatment of caries - 32,4%, in the removal of teeth - 15,3%, in professional hygiene - 19,8%, in the preventive sealing of fissures - 34,1%. The total need for dental and periodontal sanitation was 52.8%.

The sensitivity and basic electrical characteristics of the developed direct illumination matrices with charge-coupled devices and electronic multiplication were investigated at room temperatures and low illumination. Photomatrices of 576´288 and 640´512 format were designed using frame transfer architecture and 1.5-µm design rules with photosensitive cell sizes of 20´30 and 16´16 µm, respectively, and manufactured using n-channel technology with buried channel, four levels of polysilicon electrodes and two levels of metallization. To analyze the possibilities of the developed EMCCD matrices used in monitoring systems at low-light conditions, an experimental assessment of the matrices sensitivity was carried out. The assessment was based on a comparison of the luxmeter readings and Johnson's criteria using the standard 1951 USAF resolution target test table for the minimum size of line pairs distinguished by the observer (one pair consists of a dark and a light lines). The characteristics obtained with illumination of 5∙10–4 lux (glow of the starry sky with light clouds) and 10–2 lux (glow of the starry sky and the quarter of the Moon) corresponds to the parameters of generation 2+ electron-optical converters, which implies the possibility to use such matrices in night vision devices. At Åv ≈ 5∙10–4 lux, the camera with the developed EMCCD matrices will detect a human figure at the distance of about 200 m. With illumination of 10–2 lux at this distance a human figure can be identified.

A sub-THz/THz radiation detector device based on Si-MOSFET has been presented. Si-MOSFET source and gate connected to an antenna serves as a detector element. Geometry of the Si-MOSFET antenna, principle of device operation, method of estimating the sensitivity and noise equivalent power (NEP) have been described. A removable system of aspheric lenses has been developed and made for this detector device, a measured point spread function of the system of aspheric lenses has been given at the frequency 140 GHz. The detector device has been tested at the same frequency; sensitivity and NEP of the detector device have been estimated and they are equal to S=2.8×105 V/W, NEP=4.3×10-10 W (Hz)-1/2, accordingly.

The article presents the results of the analysis of orthodontic status in 176 children 6-9 years with a removable bite in Moscow. The high prevalence of dentoalveolar anomalies among children with a removable bite in Moscow (73.9 %), including anomalies in the position of the teeth (67.0%) and the ratio of dental arches (67.6 %). Significant detection of premature loss of temporary teeth (17.0 %). In the structure of anomalies of the teeth position the crowding of the teeth (45,2 %) is most represented, and among the anomalies of the ratio of dental arches - distal and excessively deep bites (respectively 46,0 % and 21 %).

Electron multiplication charge coupled devices (EMCCD) technology is an innovation first introduced slightly more than a decade ago. The EMCCD is an image sensor that is capable of detecting an isolated photon without an image intensifier. It is achieved by electron multiplication circuit that is built in the chip of ordinary CCD. Cameras with EMCCD arrays overcome limitations of getting high sensitivity with high frame rate. Traditional CCD cameras can be highly sensitive in the visible part of spectrum but at the expense of low frame rate. EMCCD can operate at very faint illumination conditions both in visible and near infrared regions. The paper presents a short technological description of EMCCD 640×512 arrays manufacturing and some parameters of the arrays that were designed and manufactured. It was shown that multiplication coefficient depends much on applied amplification voltage and can achieve 1000. Also it is shown that images can be obtained at low illumination conditions (illumination at EMCCD is near 5∙10–4 lx).

An efficient collector for high-voltage systems of electron cooling is presented. Its efficiency (ratio of the reflected electron current to the current of the main beam) is greatly improved by suppressing the reflected particle flux in the Wien filter. Secondary electrons deflect in crossed transverse electric and magnetic fields and are absorbed by a special receiver plate (secondary collector). The filter is designed so that the whole backward flow of electrons deflects even if the trajectory and main beam profile are distorted insignificantly. Experiments carried out on a special-purpose test bench show that such a filter raises the efficiency of the collector hundredfold (up to 10−6).

An energy-saving technology for production of variously structured carbon modifications from a renewable vegetable raw material, i.e., the waste of agricultural crops and peat moss, has been developed. Promising functional materials — refractory compounds (tungsten and titanium carbides) and oil sorbents possessing a combination of high operating characteristics — have been formed on the basis of the synthesized carbon modifications.

A high-perveance collector with a small secondary emission ratio has been designed for a high-voltage electron cooler. The distinctive feature of this collector is the fact that it consists of the cooled collector itself, which receives the electron flow, and a Wien filter installed ahead of it, which substantially reduces the secondary electron flux emerging from the collector. The main advantage of this design is the combination of the small secondary emission ratio and the high perveance with the small size and ease in manufacturing and adjustment. The results of calculations and experimental investigations of the combined collector are presented, and its different operating modes are investigated. The minimum attained secondary emission ratio is 5 × 10−6. The methods for further reducing this ratio are proposed.

The possibility of using carbon materials derived from renewable plant sources in the mechanochemical synthesis of titanium carbide and the manufacture of sorbents for industrial wastewater purification is considered.

The nonresonance response of silicon metal-oxide-semiconductor field-effect transistors (Si-MOSFETs) with a long channel (1–20 μm) to radiation in the frequency range 43–135 GHz is studied. The transistors are fabricated by the standard CMOS technology with 1-μm design rules. The volt-watt sensitivity and the noise equivalent power (NEP) for such detectors are estimated with the calculated effective area of the detecting element taken into account. It is shown that such transistors can operate at room temperature as broadband direct detectors of sub-THz radiation. In the 4–5 mm range of wavelengths, the volt-watt sensitivity can be as high as tens of kV/W and the NEP can amount to \({{10^{ - 11} - 10^{ - 12} W} \mathord{\left/ {\vphantom {{10^{ - 11} - 10^{ - 12} W} {\sqrt {Hz} }}} \right. \kern-\nulldelimiterspace} {\sqrt {Hz} }}\). The parameters of detectors under study can be improved by the optimization of planar antennas.

Dynamics of local morphological changes in the diabetic foot syndrome was studied in 215 patients while achieving adequate local treatment in accordance to the standards elaborated. The histological investigations data witness reduction of oedema, cellular infiltration, microcirculatory disorders in marginal zone of the wound in the treatment dynamics. In one week from the treatment beginning young granulation tissue with big quantity of vascular loops, оriented perpendicularly towards the wound surface, and multiple cravings of fibroblasts were revealed. In two weeks anactive epithelization of the wound defect in several layers was observed. From the side of the skin preserved a layer have crawled, covering the wound surface.

Problems and challenges for application of uncooled THz/sub-THz detectors for active vision systems are discussed. Mainly there speculated the detectors based on field effect transistors (FETs) and narrow-gap hot electron bolometers as they seem to be promising for using in large format broadband arrays of low-cost systems.

Silicon readout devices with input direct injection and buffered direct injection circuits and charge-coupled devices (CCD) multiplexers to be used with n + -p- or p + -n-photovoltaic (PV) multielement arrays were designed, manufactured and tested in T†=†77O300†K temperature re- gion. The on-chip testing switches attach the sources of direct injection transistors to the common load resistors to imitate the output signal of mercury cadmium telluride (MCT) photodiodes. The silicon readout devices for 2〈64 n + -p- or p+-n - linear arrays and n + -p- 2〈4〈128(144) time-delay and integration (TDI) arrays with skimming and partitioning functions were manufactured by n- or p-channel MOS technology with buried channel CCD registers. The designed CCD readout devices are driven with four- or two-phase clocking pulses.

On the installations AMBAL-M and MAL in turbulent plasma column the longitudinal current of some kiloampers was measured. The fluctuation spectrum of magnetic field was measured by azimuthal magnetic probes and expansion of plasma current by spatial modes was carried out. According to the experimental data the amplitudes of currents I n , sizes R n and shifts from axis of simmetry ΔR n for 3rd (40kHz) and 5th (72kHz) basic modes were calculated.

Responsivity (R) and noise equivalent power (NEP) of long channel unbiased silicon field effect transistors (FETs) as THz/sub-THz detectors with account of some parasitic effects were considered. These parameters and their radiation frequency ν dependences are compared with those of contemporary zero biased Schottky barrier diodes (SBDs) THz/sub-THz detectors and hot-electron bolometers (HEBs) on the base of narrow-gap mercury cadmium telluride (MCT). To describe and compare the known experimental data for Si-FET and SBD detectors the models unification was developed.

Room temperature operating n-MOSFETs (n-type metal-oxide silicon field effect transistors) used for registration of sub-THz (sub-terahertz) radiation in the frequency range ν = 53−145 GHz are considered. n-MOSFETs were manufactured by 1-μm Si CMOS technology applied to epitaxial Si-layers (d ≈15 μm) deposited on thick Si substrates (d = 640 μm). It was shown that for transistors with the channel width to length ratio W/L = 20/3 μm without any special antennas used for radiation input, the noise equivalent power (NEP) for radiation frequency ν ≈76 GHz can reach NEP ∼6×10−10 W/Hz1/2. With estimated frequency dependent antenna effective area Sest for contact wires considered as antennas, the estimated possible noise equivalent power NEPpos for n-MOSFET structures themselves can be from ∼15 to ∼103 times better in the specral range of ν ∼55–78 GHz reaching NEPpos ≈10−12 W/Hz1/2.

Analysis of four types 4×288 designed and manufactured readouts is presented. All the readouts have the direct injection input circuit with the circuits incorporated that allows testing procedure of readouts without the photodiodes attached to readout circuits. TDI registers have three delay elements between neighbouring inputs. Some characteristics of 4×288 FPAs with mercury-cadmium-telluride (MCT) arrays are presented too. Analysis have shown that in spite of different constructions of four readout types, different numbers of outputs and external service, rather similar parameters of FPAs have been obtained. Detectivity values measured for all 4×288 FPAs at operation temperature T ≈ 78 K with skimming mode included and background temperature Tb ≈295 K were in the range D*λ ≅ (1.2−1.7)×1011 cmHz1/2/W.

Infrared n-p-photodiode photodetectors based on a hybrid assembly of photosensitive elements of format 288×4 with a 56×43-μm step, made from mercury-cadmium telluride heteroepitaxial structures obtained by molecular-beam epitaxy, have been developed, fabricated, and investigated for the 8–12-μm spectral range, along with silicon multiplexers with bidirectional scanning and internal time delay and storage of the signal. The 288×4-format linear photodetector has the following mean values of voltage sensitivity, detectivity, and NETD at the maximum sensitivity: (1–3)×108V∕W, (1.5–2.0)×1011cmHz1∕2W−1, and 9mK, respectively. There are no defective channels.

The authors construct a nonlinear mathematical model describing the fracture mechanics of coal seams during explosive fracturing and drilling operations in underground mining. The model incorporates stress distribution and relaxation analysis and crack propagation along with other mechanical properties and can be implemented in determining the required layout and strength of support systems and the advance of the mine working.

Two types of experiments with a gas-box mounted in the mirror trap of the end system AMBAL-M between the central plane and the exit throat have been performed during the last year. In the experimen...