National Research University of Electronic Technology

Background Glucose absorption into the bloodstream and body tissues poses a significant challenge in peritoneal dialysis, resulting in a reduced ultrafiltration rate and requiring the use of a dialysate with a high initial glucose concentration. The goal of the presented study is to develop a system for controlling glucose concentration and ultrafiltration rate. Methods The paper proposes a method for the automatic control of glucose infusion to maintain a given glucose concentration and ultrafiltration rate. This method utilizes an optical glucose monitor and a control strategy that combines feedback with prediction of peritoneal volume. Computer simulations were conducted to evaluate the efficiency of the method under various conditions, including errors in the glucose monitor, inaccuracies in parameter determination, and drift in patient parameters. Additionally, the method was compared to an open loop. Results and Conclusions Our results demonstrate the feasibility of using noninvasive glucose monitoring systems and the proposed control strategy to maintain a given dialysate glucose concentration. The proposed closed loop provides more stable maintenance of glucose concentration and ultrafiltration rate for at least 12 h, even in the presence of significant glucometer errors, compared to continuous glucose infusion.

In an experimental surgical study, laser technologies and various types of biological compounds effectiveness, collagen-containing and collagen-free, in closing a skin defect with subsequent excision and closure with counter flaps using the A.A. Limberg surgeon method were studied. The research was performed on 27 male Wistar laboratory rats weighing 200-250 g, which were divided into 3 groups of 9 species each to obtain representative results: 1 - control group with flap plastic surgery with counter flaps using interrupted sutures at intervals of 5 mm; 2 - experimental group using laser technologies and biological composition 1 (BC-1) containing serum albumin 25 wt.%, collagen 8 wt.%, indocyanine green 0.1 wt.%, single-wall carbon nanotubes 0.1 wt.%, water); 3 - experimental group using laser technologies and biological composition 2 (BC-2) containing serum albumin 25 wt.%, indocyanine green 0.1 wt.%, single-wall carbon nanotubes 0.1 wt.%, water. On days 7, 14, 21, laboratory animals were taken out of the experiment, 3 individuals at random, under inhalation anesthesia with isoflurane (USA) in a specialized CO2 chamber. The wound healing time, the thickness of the formed scar connection, the tensile strength of the suture, the morphological structure of the connection using hematoxylin and eosin staining (histological sections were studied in an Olympus-cx312 binocular microscope), and its cosmetic characteristics according to the international Scar scale were assessed. The use of BS-2, containing serum albumin 25 wt.%, indocyanine green 0.1 wt.%, single-wall carbon nanotubes 0.1 wt.%, water, under laser exposure is a reliable method for connecting the edges of a wound defect in flap plastic surgery, not inferior in strength to a nodal suture on the 21st day, reduces the time of primary scar formation to 8.1 ± 0.7, and has optimal cosmetic characteristics.

The issues of metrological support of packet data transmission networks are considered. The main problems of traceability in the transmission of measurement units of parameters of packet data transmission networks to measuring instruments are described. The results of the analysis of the fleet of measuring instruments traceable to the State primary standard of units of quantity of transmitted (received) information (data) and units of values of parameters of packet data transmission networks GET 200-2023 are presented. The cardinal differences between the methods of measuring the parameters of packet networks implemented using GET 200-2023 or measuring instruments and working standards are considered. Network parameters that determine their integrity and stability include bandwidth, packet transmission delay, packet transmission delay variation, and packet loss coefficient. It is established that when measuring the parameters of networks with operational traffic, the fractal and avalanche-like behavior of packet communication networks complicates the application of statistical mathematics and classical error theory, and measurements turn into an iterative research process. It is shown that the method of using rigid logic implemented in GET 200-2023 to obtain a synchro pulse associated with a logical event allows avoiding the problem of uncertainty of the time of a logical event, characteristic of measuring instruments based on software logic. A number of issues of metrological support for packet networks are noted, which are currently not covered by legislative acts and do not have an adequate technical solution. Government agencies in the field of legislative metrology and all interested parties are invited to pay attention to this.

This article presents the fundamental principles of creating a Russian-made implantable neural interface blocking the transmission of pain signals in the spinal cord. Particular attention is paid to the use of Russian-produced microelectronic systems created on the basis of general technology theory.

Objective. Improving the effectiveness of surgical treatment for dental patients through the experimental development of a laser seam for soft tissues in the maxillofacial area using laser radiation and biopolymer. Materials and methods. The experimental research model was created on 8 laboratory rabbits of the Chinchilla breed. Linear wounds on the skin were made with a surgical scalpel No. 15C and sutured. All rabbits were divided into 3 research groups: group 1, wounds were sutured with Prolen 5.0 thread; group 2, the edges of the wounds were joined using laser tissue welding with a laser device with a wavelength of 970 nm and Bioadhesive No. 1 based on bovine serum albumin and indocyanine green; group 3, the edges of the wounds were joined using laser tissue welding with a laser device with a wavelength of 970 nm and Bioadhesive No. 2 based on bovine serum albumin, indocyanine green, and single-walled carbon nanotubes. In the postoperative period, the severity of edema, intensity of hyperemia, and the time of wound epithelialization were assessed on days 1, 3, 5, and 10 in points. Results. Experimental studies on rabbits in vivo showed that the best regeneration occurred when the edges of wounds were joined using laser skin welding with laser radiation and Biopreparation No. 2. In the postoperative period, there was minimal swelling and hyperemia, no suture dehiscence or tissue necrosis was observed, and earlier epithelialization and an aesthetic scar were noted. Conclusion. The use of laser radiation and biopreparations is a promising method for joining the edges of wounds on the skin, as it accelerates regeneration and forms an aesthetic scar.

Introduction. The number of surgical interventions in the oral cavity is steadily increasing, as dental diseases are among the most common health conditions today. Consequently, the choice of suturing techniques during surgical procedures is directly linked to the quality of dental care. One promising approach is laser tissue soldering, which enables rapid and airtight tissue bonding under sterile wound conditions, leading to faster healing and reduced scar formation. Objective. To enhance the effectiveness of surgical treatment in dental patients by experimentally developing a laser tissue soldering technique for the oral mucosa using laser radiation and a biocompatible soldering material. Materials and methods. The experimental study was conducted on 16 chinchilla breed laboratory rabbits. Linear wounds were created on the oral mucosa using a scalpel and then sutured. The animals were divided into two study groups: 1) the wounds were sutured using Prolene 5.0 thread; 2) the wound edges were joined using the laser tissue soldering technique, employing a 970 nm wavelength laser device and a biocompatible solder composed of bovine serum albumin, indocyanine green, single-walled carbon nanotubes, type I collagen, and Prolene 5.0 thread. Postoperative assessments included pain intensity, swelling severity, and the degree of hyperemia coloration at the surgical site on days 1, 3, and 5, using a scoring system. Results. In vivo experimental studies demonstrated that laser tissue soldering with laser radiation and biocompatible solder provided superior wound regeneration. Postoperatively, pain and swelling were minimal, hyperemia was not pronounced, and no cases of suture dehiscence or tissue necrosis were observed. The laser-formed suture site exhibited early epithelialization, and the resulting scar was extremely thin and nearly indistinguishable from the surrounding tissue. Conclusion. The use of laser radiation in combination with biocompatible solder represents a promising technique for wound closure in the oral cavity, as it enables painless acceleration of postoperative regenerative processes with minimal risk of hypertrophic scar formation.

Heterostructures with an active region based on GaAs/Ge/GaAs layers are of interest for creating terahertz devices and topological insulators. The optical and electrical properties of such devices depend, to a great extent, on the conditions of their synthesis. In this work, the structure of GaAs layers in GaAs/Ge/GaAs heterostructures grown on a GaAs(001) substrate by molecular-beam epitaxy under process conditions providing a 90° rotation of the crystal lattices of the upper and lower GaAs layers in samples of one type and no rotation in samples of the other type is examined. The synthesized hetero-structures are studied by transmission electron microscopy and electron-diffraction analysis using thin cross-sectional foils prepared by the focused-ion-beam method. It is found that the GaAs/Ge/GaAs layers in samples of both types have a high crystal quality, but stacking faults and antiphase domains are formed in the GaAs layers located above the Ge layer. The relative orientation of the upper and lower GaAs layers in GaAs/Ge/GaAs is identified by comparing the intensity distributions in the disks and 002 in the diffraction patterns obtained by convergent-beam electron diffraction. It is demonstrated by simulating the patterns that the orientation of the sample along the [310] zone axis is optimum for detecting differences between the diffraction patterns on pseudo-forbidden disks and 002. The experimental diffraction patterns obtained under such conditions confirm the identical orientation of the crystal lattices of the upper and lower GaAs layers in samples of one type and the rotation of the lattices of these layers by 90° about the [001] direction in the samples of the other type.