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Background. The use of nanotechnology achievements in medicine opens up prospects for the development and improvement of means and methods of prevention and treatment of diseases of various origins. Carbon nanotubes (CNTs) are a product of modern nanotechnologies, and in addition to their unique physical and chemical properties, they are promising for practical applications in medicine. CNTs are one of the most popular (comparable only with silver and titanium dioxide nanoparticles) objects of nanotoxicological research. Data on the effect of CNTs on blood cells are contradictory, so additional studies are necessary. Objective. To assess the activation capabilities of immobilized carbon nanotubes by the rate of adhesion of blood cell elements to their surface in vitro. Design and methods. Hemocontact interaction was carried out in bench conditions using donor blood in rotational mode. Blood samples were taken before the start of the experiment and after 5, 20, 40 and 60 min. Changes in the indicators of cell blood populations using the hematology analyzer SySmex XT 1800i (26 parameters). 50 experiments were conducted. To analyze the activation functions, a speed-time adhesive profile was used. Results. The highest rates of activation of cellular elements of the blood were recorded in contact with multi-walled carbon nanotubes SiloMUNT. Conclusion. The results of the study can be further implemented in the procedure of low-volume hemoperfusion in clinical practice.

Rare (orphan) diseases are an urgent unmet biomedical problem. Tremendous efforts and resources are expended for the search for cures for these diseases. Zebrafish can provide a powerful screening tool for novel orphan drugs, and may also deepen our mechanistic understanding of such rare pathological conditions. Here, we discuss various models of orphan diseases of the nervous system on zebrafish, and outline associated problems, limitations and prospects in the context of the development of personalized medicine.

This paper presents a comparison of chemical and plasma electrolyte polishing methods for preparing a copper substrate for graphene synthesis by chemical vapour deposition. It is shown that in order to achieve the most uniform morphology of the surface of the copper substrate, it is preferable to use the electrolyte-plasma polishing method. With its help, the proportion of multilayer regions in the graphene coating obtained as a result of CVD synthesis decreases. The obtained results may serve a recommendation for creating a graphene coating with specified parameters.

The article analyzes the scope, technologies and principles of wireless local area networks, which allowed to mark the “bottlenecks” of these technologies, which need special attention when designing: the problem of hidden node; mutual interference between neighboring cells (intrasystem EMC); intersystem interference; providing QoS for responsible applications; expansion of wireless local area networks; the impact of network deployment features. The methods used to solve EMC problems in wireless local area networks are shown and their efficiency is analyzed: the mechanism of access to the transmission medium; IEEE 802.11e (QoS) standard; additional standards designed to reduce the impact of interference (802.11 h and k); coding and modulation. It is shown that the accounting of intrasystem and intersystem interference should be carried out in the early stages of design of wireless local area networks. It is shown that the existing mechanisms of access to the transmission medium are designed to organize the conflict-free operation of transceivers within a single access point and are vulnerable to interference created by transmission stations of neighboring access points. The dynamic sensitivity control algorithm is aimed at partially solving this problem, however, the main disadvantage of the DCC algorithm proposed for use in Wi-Fi 6 is that stations located near access points have a higher probability of access to the environment due to a higher signal level. Relative to electromagnetic interference, which leads to a shorter detection range of the carrier. That requires the development of advanced mechanisms to control the sensitivity of the service area of access points. Based on the analysis, a conclusion is made about the need to develop a methodology for designing wireless local area networks based on information systems, taking into account electromagnetic interference. Which will reduce the time of their design and increase the efficiency of their further operation.

The problem of traffic control and management for the purpose of forecasting and prevention of congestion of a telecommunication network is considered. The definition of the concept of traffic policy is given. The solution of traffic control problems is based on the application of a policy that allows the harmonious distribution of information flow. A promising way to prevent congestion is the management of traffic parameters ‒ policing and shaping, i.e the management of statistical characteristics of traffic. The necessity of using probabilistic and statistical methods of traffic control, based on correlation and regression analysis, is substantiated. The concept of end-to-end network diagnostics is considered. End-to-end management includes network management as a whole, congestion management and traffic parameters management. Further development of traffic policy is the use of differentiated and integrated services. The method involves the dynamic allocation of bandwidth of transmission channels between users based on their priorities. This approach avoids periodic local congestion of routes that have been identified as optimal at the current stage. The algorithm involves the selection of routes according to the criterion of equable loading of transmission lines. To implement a policy of traffic with differentiated services, it is necessary to solve the problem of flow distribution between locally optimal or quasi-optimal routes in real time. The process model of the total flow formation due to the imposition of separate flows from different sources is considered. It is shown that, under the conditions of maintaining the balance of network flows the intensities of flows to nodes with limited buffer memory exceed the corresponding intensity of the network with unlimited memory. This saves storage and reduces packet delays due to latency in switching buffers.

This article is about user’s rights to files or directories. The GNU\Linux systems have many great security features, but one of the most important is the file permissions system. Methods for organizing user rights in GNU\Linux systems, such as granting rights to each user individually and grouping users with the same or similar rights into groups, are discussed. The concept of operating system user and superuser is formed. The benefits of grouping users by access level have been identified. The criteria for dividing users into groups are analyzed, depending on the format of computer use, the structure of the organization that owns a particular computer and the number and positions of people who will work with it. Also, the benefit of the mechanism of organizing users into groups to manage service users of services running in the system is considered. It is said that any file and directory in Linux has an owner user and an owner group. That is, any file and directory belongs to some system user and some group. In addition, any file and directory has three access rights groups: one for the owner user, one for members of the owner group, and one for all other users on the system. Each group consists of the rights to read, write and execute the file for execution. The format of saving rights to a file or directory and the mechanism of checking access to a file or directory are considered. An explanation is given of what the right to read, the right to modify and the right to execute means for the file and for the directory. It is with the help of these sets of permissions that the permissions of files in linux are established. Each user can only have full access to files that he owns or those that he is allowed to access. Only the Root user can work with all files, regardless of their set of permissions.

The objectivewas to study the effect of changing the anglconvergence of the abutment walls, depending on their height, as well as the number of supports, on the accuracy of fitting metal-ceramic prostheses to the abutments.It was studied 72 constructions: prostheses on single abutments with abutment heights from 3 mm to 9 mm with an increase in height of 2 mm, an angle of convergence of the abutment walls from 0° to 10° with an increase in convergence of 2° in the amount of 24 prostheses; 24 framework designs supported by two abutments, with the same parameters (height and angle of inclination of the abutment walls) and prostheses supported by three abutments in the amount of 24 designs. The abutments were milled from a titanium alloy Ti-6Al-4V, and the prostheses were cast from a cobalt-chrome alloy. During fabrication of the prostheses, a compensation varnish was applied to the respective abutments to create a gap between the framework and the abutment for a 50 μm thick cement film. The crown prostheses were cemented onto the abutments with GC Fuji + glass-ionomer cement, followed by vertical sawing in the medio-distal direction. After sawing, the gaps between the inner edges of the prostheses walls and the outer edges of the abutment walls were measured using a «Levenhuk DTX 90» digital microscope (Russia) at x100 magnification.Abatement height 3 mm with any number of supports and 5 mm with up to 3 supports do not need taper for precise fitting. In 5 mm abatements and 3 and more supports minimal required taper is 2°. Seven mm singular abatement requires 4° taper, but the increased number of supports enhances it up to 6°. For 9 mm abatement optimal abatement taper for the best fitting is 8°.The study showed the relationship between the fitting accuracy and the change in the abutment taper, their height, and the number of supports in the structure.Изучение влияния изменения конусности абатментов в зависимости от их высоты, а также количества опор на точность припасовки каркасов металлокерамических протезов к абатментам.В исследовании изучались 72 конструкции: каркасы на одиночных абатментах (24 конструкции) с высотой абатментов от 3 до 9 мм с шагом увеличения высоты 2 мм, угол наклона стенок абатментов от 0 до 10° с шагом увеличения наклона 2°; 24 конструкции каркасов с опорой на два абатмента, с теми же параметрами (высотой и углом наклона стенок абатментов) и каркасы с опорой на 3 абатмента (24 конструкции). Абатменты были изготовлены методом фрезерования из титанового сплава Ti-6Al-4V, каркасы — методом литья из кобальт-хромового сплава. При изготовлении каркасов на соответствующие абатменты наносили компенсационный лак в целях создания зазора между каркасом и абатментом для пленки цемента толщиной 50 мкм. Каркасы коронок были зацементированы на абатменты стеклоиономерным цементом GC Fuji+ с последующим вертикальным распилом в медио-дистальном направлении. После распиливания измеряли зазоры между внутренними краями стенок каркасов и внешними краями стенок абатментов с помощью цифрового микроскопа «Levenhuk DTX 90» (Россия) при увеличении в 100 раз.При высоте абатментов 3 мм с любым числом опор и 5 мм до 3 опор в конструкции для точной припасовки не требуется конусность, но при высоте 5 мм абатментов и 3 опор требуется минимальная конусность стенок 2°. При высоте абатмента 7 мм в одиночной конструкции угол наклона 4° достаточен для точной припасовки, но при увеличении числа опор в конструкции и высоте 7 мм для точной припасовки требуется больший угол наклона (6°). Для наилучшей точности припасовки каркасов к абатментам высотой 9 мм оптимальной конусностью абатментов является 8°.Изменение конусности опорных абатментов влияет на точность припасовки в зависимости от высоты абатментов и количества опор в конструкции.

The results of testing, debugging, and adjusting the ARV-MA digital excitation-regulator for the TZFA-110-2A asynchronous turbogenerator of power station No. 22 of the Moscow power system based on the Power Transmission Research Institute electrodynamic power system model application are considered.

The compensation of cell motion is an important step in single-particle tracking analysis of live cells. This step is required in most of the cases, since the movement of subcellular foci is superimposed by the movement and deformation of the cell, while only the local motion of the foci is important to be analysed. The cell motion and deformation compensation is usually performed by means of image registration. There are a number of approaches with different models and properties presented in the literature that perform cell image registration. However, the evaluation of the registration approach quality on real data is a tricky problem due to the fact that some stable features in the images with a priori no local motion are needed. In this paper we propose a methodology for creating live cell nuclei image sequences with stable features imposed. The features are defined using the regions of fluorescence bleaching invoked by the UV laser. Data with different deformations are acquired and can be used for evaluation of the cell image registration methods. Along with that, we describe an image analysis technique and a metric that can characterize the quality of the method quantitatively. The proposed methodology allows building a ground truth dataset for testing and thoroughly evaluating cell image registration methods.

Results of sociological study done among teachers of the system postgraduate education of doctors stomatologists were presented. There were determined the most significant Bologne declaration positions for the use in postgraduate education of doctors stomatologist. The basic obstacles for these positions realization in native postgraduate education were uncovered.

New way of using alternating magnetic field is described. Basic functional description of new treatment and diagnostic offered (patents of RF No75294 and 75314), which included digital plethysmograph and regulation of angiotonic microcirculation channel device. Comparative estimation of clinical and functional indiced of regional blood flow of patients in the main group and in the control group showed a positive correlation. Expressed influence of alternating magnetic field on frequency of oscillations pulse vessels microcircution channel and acceleration of leveling disorder of blood circulation in tissue after surgical treatment was proved.

Reaction of the pulp to degree-by-degree changes (from 3 to 18 degrees) in inclination of lateral walls of abutment teeth during preparation for cermet dentures was studied by the functional diagnosis methods (electroodontodiagnosis, rheodentography) in 50 patients with intact abutment teeth. Changes in dental pulp electric conductivity and hemodynamics depended on the inclination angle formed during preparation. The optimal safe angle of the lateral wall inclination was determined to be 3-12 degrees. Increase of the angle (12 degrees) can lead to traumatic pulpitis.