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The article presents the construction of a simulation model of the operation of a container gantry crane at a cargo terminal to determine the parameters of the intensity of use of the crane as a whole and its individual mechanisms. The simulation model is being built in order to provide a more reasonable choice of crane for newly designed terminals and to assist in the operation of already in operation lifting machines to reduce accidents and improve the safety of work at terminals. To build the model, an analysis of the structure of container terminals was carried out, significant variable and constant parameters of the three main elements of the terminal were identified: the site, cargo flow and the actual lifting machine. Based on the data obtained as a result of the analysis, a simulation model in the Python programming language is built. To check the model for compliance with reality, the simulation results were compared with the readings of the remote monitoring system of a really operated gantry container crane. The comparison confirmed the assumption that the constructed model correctly reflects the features of the lifting machine at the container terminal and can be used to assess the operating mode of the crane and its mechanisms.

Large-scale introduction of automated processes into medical practice, including ophthalmology, can simplify the diagnosis and treatment of patients. Being part of the general biological system of the body, the eye is an exemplary object of mathematical modeling targeted at treatment optimization, — e. g. when choosing a surgical tool for retinal detachment surgery.Purpose: to develop a software for automatic calculation of the individual length of the circular band to be used in retinal detachment treatment in order to achieve the optimal height of scleral indentation.Materials and methods. The study had a dual task: 1) to determine the correlation between the axial length (AL) and the equatorial diameter of the eyeball, measured by ultrasonic A- and B-scanning in healthy patients (90 eyes), and 2) to develop formulas for calculating the optimal length of the scleral buckle.Results. The formulas found to be effective in clinical practice were used to develop a software calculating the required length of the 3-mm wide circular band made of pourous silicon from the patient’s axial length. The software, called Circular Scleral Buckle Length, operates under Windows or Linux, is freely downloadable using a QR-code.Conclusion. The software greatly facilitates the determination of the optimal length of the buckling material for each patient, simplifies the operation of circular scleral buckling, reduces the time of the operation, minimizes the risk of complications, and ensures favorable anatomical and functional results.

The influences of cosmic radiation on atoms and molecules in the Earth's atmosphere were observed with subsequent transformation of atoms, molecules of gases, as well as development of states of oxygen deficiency (hypoxic) in biological organisms, some recommended ways of such disorders correction. Purposes of this work were to study radiation effects in ionosphere with subsequent high-energy transformations of atoms, molecules of gases at different heights above the Earth surface; interaction of some high-energy atmospheric particles with biological objects at near Earth's heights up to 5.500 m above sea level (a.s.l.), and oxygen roles in consequences of biological organisms’ irradiation. Methods. Analysis of results of satellite and rocket observations of the Earth atmosphere gases exploring at different altitudes a.s.l. Investigations in mountain conditions at EMBS research station of the National Academy of Sciences of Ukraine: comparative analysis of results of long-term observation of patients using standard laboratory methods, complex of methodological techniques: clinical, physiological studies of respiratory, cardiovascular systems; hematological, immunological states; functional state of higher nervous activity, mental and neurotic state; antihypoxants use, histochemical, biophysical methods, math modelling, others. Results. The last data obtained during the satellites atmosphere exploring were presented: studies of influences on the structure of atoms, molecules in atmosphere, concentrations of gases from ionosphere to the Earth surface, such phenomena as photochemical processes, photoionization. The notion “information” was discussed basing on phenomena, described in the article. Described studies of gases particles modification, oxygen deficiency in organisms (hypoxic states) were supplemented with the results of irradiated Chernobyl patients’ examinations, rehabilitation by Ukrainian doctors, scientists in mountain conditions. Conclusions. Phenomena of solar radiation influence on atoms, molecules and molecular complexes in the Earth's atmosphere were observed. The main attention was concentrated on the studies of gases concentrations at different heights with linked effects of oxygen roles in consequences of organisms’ irradiation and rehabilitation. Practical recommendations for patients’ medical care and rehabilitation were done.

Abstract We study the processes of dynamical diffraction of the plane X-ray waves on the graphene film/SiC substrate system in the case of the Bragg diffraction geometry. The statistical dynamical theory of X-ray diffraction in imperfect crystals is applied to the case of real quasi-two-dimensional systems. The necessity of the taking into account of the variability of the lattice parameter of multilayer graphene, as well as the influence of thickness on the thermal Debye–Waller factor at the calculation of the complex structural factors and Fourier components of polarizability, is demonstrated. It is shown that the change of the structural characteristics of the 3-layer graphene/substrate system, as well as its strained state, leads to a significant change in the diffraction profiles, which makes it possible to determine the characteristics by the X-ray diffraction method.

This paper proposes a new post-quantum signature scheme, Syrga2, based on hash functions. As known, existing post-quantum algorithms are classified based on their structures. The proposed Syrga2 scheme belongs to the class of multi-use signatures with state retention. A distinctive feature of state-retaining signatures is achieving a compromise between performance and signature size. This scheme enables the creation of a secure signature for r messages using a single pair of secret and public keys. The strength of signature algorithms based on hash functions depends on the properties of the hash function used in their structure. Additionally, for such algorithms, it is possible to specify the security level precisely. In the proposed scheme, the HBC-256 algorithm developed at the Institute of Information and Computational Technologies (IICT) is used as the hash function. The security of the HBC-256 algorithm has been thoroughly studied in other works by the authors. In contrast to the Syrga1 scheme presented in previous works by the authors, the Syrga2 scheme provides for the definition of different security levels determined by the parameter τ. This paper experimentally demonstrates the impossibility of breaking the proposed scheme using a chosen-plaintext attack. Additionally, the scheme’s performance is evaluated for signature creation, signing, and message verification.

Radiation is an important and dangerous factor in contemporary reality in some regions of industrial countries, after technological accidents at nuclear objects, chemical enterprises, etc. This is also the reality of some contemporary military activities and armed conflicts. Radiation damages of organisms can arise also due to the natural reasons — aviation or space flights at high altitudes or even long stay on mountain heights. Natural reasons of such effects have been studied insufficiently for today. Purpose. To outline briefly some results of studies of the characteristics of ionizing radiation at different heights above the Earth. To describe briefly the influence of radiation factors on biological organisms and main mechanisms of these effects. To describe effects that cause pathological changes in organisms of people exposed to the low doses of radiation for a long time and methods of post-radiation rehabilitation of affected people in highlands conditions. Methods. Space satellite exploring of the Earth atmosphere at different altitudes above sea level with measurements of different characteristics of solar and galactic radiation (mainly X-ray, gamma radiation, as well as other types of ionizing radiation in some other ranges). Comparative analysis of the results of longterm observation of patients in hospital conditions using many standard laboratory methods of their states examinations. The conducted scientific research consisted of a complex of methodological techniques and approaches: clinical and physiological studies of respiratory and cardiovascular systems, hematological and immunological states, and functional state of higher nervous activity, mental and neurotic state; administration of antihypoxants, histochemical, biophysical and other methods were used to evaluate oxybiotic processes. Mathematical processing of the results, as well as methods of mathematical modeling was applied. Results. The results of the measurements of ionizing radiation levels during the satellite exploring of the Earth atmosphere at different altitudes were analyzed and presented in schemes. The mechanisms of damaging radiation effects in organisms at nano level were described: water radiolysis, “oxygen effect” as radio sensitizer, formation of various types of free radicals and peroxides with future consequences for organic compounds, cells, tissues, organs, and organisms. The results of medical treatment and rehabilitation at the EMBS of the persons irradiated by the low doses of radiation were presented, observed and discussed. Many of represented results were obtained thanks to the collective work of the great commands of our predecessors in science who searched for the possibilities of medical treatment and rehabilitation of patients who obtained low doses of radiation during long time. The contemporary results of possibilities of some developed pathological states pharmacological corrections were discussed; practical recommendations were done. Conclusions. Some of results of fulfilled works, which can be valuable in the treatment and rehabilitation of people of various contingents exposed to low doses of radiation of various natures for a long time, were presented. The outlined recommendations can be offered to persons of various radiation risk contingents for the purposes of their rehabilitation, in practice of health care, etc.

This article published the materials of the round table “Bioengineering in ophthalmology” (OphthalmicBioengineering), held on May 13, 2021 as part of the international conference Ural Symposium on Biomedical Engineering, Radioelectronics and Information Technology (USBEREIT). USBEREIT is held under the auspices of the IEEE Engineering in Medicine and Biology Society. The article presents reports on: metrological aspects of registration of tonometric and electrophysiological signals in ophthalmic diagnostics; approaches to modeling the processes of pulse blood filling of the eye with the determination of hemodynamic parameters; retinotoxicity based on electrophysiological signals; analysis of electrophysiological signals in the frequency-time domain and its application in clinical practice; extraction and analysis of specialized data obtained from the electrophysiological medical device; as well as diagnosing retinal diseases based on optical coherence tomography using machine learning.

Infectious endophthalmitis (EF) is a serious problem in modern ophthalmology, which can lead to irreversible consequences for the patient’s visual functions. Timely diagnosis and timely treatment are the “key” to the successful resolution of the process. Matrix-assisted laser desorption/ionization method using matrix laser desorption/ionization. Time-of-flight mass spectrometry, or MALDI-TOF MS, aimed at determining the mass of the investigated “unknown” molecules by ionization, followed by separation and determination of the ratio of their mass to charge (m/z) with positive and negative signs. The method allows ionizing biological macromolecules (peptides, proteins, DNA, oligonucleotides, oligo- and lipopolysaccharides, etc.) as part of a special substance — a matrix — under the influence of a laser. The resulting ions are separated during the time-of-flight analyzer due to different velocity of movement, inversely proportional to the mass of the ion. Based on the source of the ionization source before the detector, the speed of movement and the ratio of mass to charge (m/z) for each ion are calculated: the heavier the molecule, the longer its flight duration. To identify bacteria, the spectrum of proteins is determined directly from the bacterial cell without preliminary long-term sample preparation. For each type of microorganism, a characteristic set of proteins (biomarkers) is formed, obtained on the basis of analysis of at least 50 mass spectra of this type (almost 100 % accuracy). This mechanism leads to the fact that different biological microorganisms form patterns, or spectra, which makes it possible to identify them by the type of “fingerprint”, while the research time itself is usually not several minutes. This article presents a clinical case of the use of MALDI-TOF MS in the diagnosis of endophthalmitis.

This article is a continuation of a series of publications on the results of an experimental study on the possibilities of using quantum dots, as well as bioconjugates based on them as a promising treatment for inflammatory diseases of the eye. Of the whole variety of microorganisms, Pseudomonas aeruginosa (Pa) is the most formidable pathogen, leading to pronounced, sometimes fatal, changes throughout the body in general, and in the eye in particular, in connection with which it receives close attention from bacteriologists and specialists dealing with the treatment of pathologies caused by this microorganism. Now, the search for effective methods to combat this pathogen is one of the priorities of world health care.This article presents an analysis of the anti-infectious activity of bioconjugates based on quantum dots KTCdTe / CdMPA710 and KTInP / ZnSe / ZnS650 in synergy with III generation cephalosporin (Cefotaxin) against nosocomial Pa strains. Cultures of microorganisms, in the amount of 30 Petri dishes, were incubated in a thermostat at 350C for 18 hours (in the dark and under a source of photoexcitation). As a source of photoexcitation (the emission spectrum of the source corresponded to the absorption spectrum of QDs), we used an LED strip connected to an uninterruptible power supply battery placed in a thermostat. Evaluation of the effectiveness of the impact was carried out using the disk-diffusion method with the measurement of effective growth retardation zones (GRZ). According to the results of the study, it was revealed that the use of the obtained bioconjugate (QD + AB) significantly increases the ZZR.

Purpose. To assess remote results of our method of macular hole (MH) surgery without postsurgical vitreous cavity tamponade. Material and methods. 34 eyes of34 patients were operated for full-thickness MH 100 to 932 (558.5 ± 50.9) microns in diameter with no vitreous cavity tamponade. Before surgery, best corrected visual acuity (BCVA) was 0.02 to 0.25 (0.11±0.02). The operation included 3-port 25—27 G vitrectomy, separation of posterior hyaloid membrane, staining and removal of the internal limiting membrane (ILM) with subsequent ex­change of salt solution for air. The hole edges were passively (without touching the retina) pulled towards the center using an extrusion cannula through air supplied into the vitreous cavity under the pressure of 20—25 mm Hg. After that, 0.05 to 0.1 ml of platelet rich plasma (PRP) of the patient was applied to macular hole zone. In 2 minutes, a fibrin film was formed at the place of application which was pressed to the retina by injecting 0.5 ml of Perfluororganic Compound liquid (PFCL) into the vitreous cavity. PFCL was exposed for 3 minutes, whereupon it was passively aspirated. The operation was completed by air exchanged for salt solution. High specific weight of PFCL facilitated a tight adhe­sion of fibrin film to the retina. The follow-up period was 1 to 20 months (7.9±0.8 on average). Results. After the surgery, complete closure of the macular hole was achieved in 32 of 34 cases (94.1%). No intraoperative or postoperative complications were observed. Postsurgical BCVA improved to 0.3—0,7(0.50 ± 0.05). At the initial stage of the study, a recurrence ofMH took place in two cases associated with partial mechanical displacement of the fibrin film by the cannula during PFCL removal. Conclusions. The proposed method of macular hole surgery avoiding postoperative vitreous cavity tamponade with gas or another vitreous substitute is effective, speeds up the rehabilitation and may be used in routine clinical practice, especially in patients with the only seeing eye, those with a transparent lens, those who need to take a plane or rise at great heights soon after the surgery, as well as those at risk of increased IOP or unable to sustain a forced head position even for a short time span.

Electroretinography is a non-invasive electrophysiological method standardized by the International Society for Clinical Electrophysiology of Vision (ISCEV). Electroretinography has been used for the clinical application and standardization of electrophysiological protocols for diagnosing the retina since 1989. Electroretinography become fundamental ophthalmological research method that may assesses the state of the retina. To transfer clinical practice to patients the establishment of standardized protocols is an important step. It is important for monitoring successful molecular therapy in retinal degeneration. Retinitis pigmentosa or achromatopsia and, consequently, affected cones or rods photoreceptors is corresponded to complete absent of electrical response. Thus, detection of even modest improvements after therapeutic treatment is required. Standardized protocols allow the implementation of electroretinography under conditions of optimization of sensitivity and specificity during clinical trials. It should be noted that the literature on retinal diseases demonstrates clinical cases in which patients may have several retinal diseases at the same time. In such cases, it is necessary to detect a group of characteristics of electrophysiological signals with high accuracy to improve the application of various diagnostic solutions. The classification of electroretinogram signals depends on the quality of labeled biomedical information or databases, in addition to this, the accuracy of the classification results obtained depends not only on computer technology, but also on the quality of the input data. To date, the analysis of electroretinogram signals is realized manually and largely depends on the experience of clinicians. The development of automated algorithms for analyzing electroretinogram signals may simplify routine processes and improve the quality of diagnosing eye diseases. This article describes the formation of the parameters of pediatric electroretinogram database parameters for the development of doctor’s decision-making algorithm. The signal parameters were obtained by extracting the parameters from the wavelet scalogram of the electroretinogram signal using digital image processing and machine learning methods.

This article presents the third part of an experimental study on the prospects and possibilities of using quantum dots and bioconjugates created on their basis in the treatment of inflammatory diseases of the eye. Taking into account the previously obtained results on the possibility of “safe” use of CdTe/Cd and InP/ZnSe/ZnS quantum dots on an animal model under conditions of intravitreal administration, the aim of the current stage was to analyze their antimicrobial activity in a bacteriological laboratory.Materials and methods. As QDs, we took two types of artificial fluorophores capable of generating superoxide radicals synthesized according to a special technical assignment at the Federal State Unitary Enterprise “Research Institute of Applied Acoustics”, Dubna, Moscow Region: type 1 — colloidal solution of QD CdTe / Cd MPA 710 10 % of the mass. Type 2 — colloidal solution of QD InP / ZnSe / ZnS 650 10 % wt. The study included “museum” and nosocomial strains of microorganisms, and the activity of points was assessed using the diskdiffusion method, followed by an assessment of the zones of inhibition of bacterial growth. Concentrations of 0.1 %, 0.01 %, and 0.001 % quantum dots were tested, as well as solutions of bioconjugates (antibiotic + quantum dots) of Vancomycin, Levofloxacin, Ceftazidime and Cefotaxime.Results. Based on the data obtained, it was concluded that quantum dots potentiate the action of the sensitivity of individual microorganisms, both outpatient and hospital strains.

The problem of chemo/antibiotic resistance in modern medicine remains relevant today. The sensitivity of microorganisms (MO) determines the range of drugs used, which ultimately affects the effectiveness of treatment and the prognosis for the patient. However, taking into account the adaptation process of individual strains of MO, the uncontrolled use of antibiotics will inevitably lead to the maintenance of the so-called crisis of antibiotic resistance throughout the world, as well as the formation of a vicious circle that reduces the functional and anatomical outcomes of the treatment of any inflammatory diseases, including ophthalmological ones. This article presents the process of experimental creation and certification, assessment of the physicochemical properties of quantum dots, as well as biological nanoconjugates as an option for overcoming the antibiotic resistance of certain strains of microorganisms in the treatment of infectious and inflammatory pathology in ophthalmology, in particular endophthalmitis. Also, an animal model has demonstrated the safety of using InP / ZnSe / ZnS 660 quantum dot solutions for intravitreal administration in pure form and in combination with antibiotics.

Endophthalmitis remains one of the most formidable complications of surgery in ophthalmology, leading to significant functional and anatomical changes. The “gold” standard of treatment for this pathology is the installation of intravenous injections of antibacterial drugs, but taking into account the number and type of pathogens, the growth of antibiotic resistance, the search for alternative methods of treatment of endophthalmitis remains relevant. Colloidal quantum dots, which are nanoscale semiconductor crystals with simulated optical and electronic properties due to changes in their volume, composition, and surface connections, are of interest for research in this direction. This article presents the process of synthesis of CT and bioconjugates based on them in order to assess ophthalmotoxicity with the prospect of further use in the treatment of endophthalmitis. The study was divided into 4 stages, starting with the determination of the required technical specification in order to select the appropriate type of quantum dots taking into account the physical and chemical characteristics (Stage 1), the synthesis of quantum dots (Stage 2), the preparation and titration of a solution of quantum dots of various concentrations for implantation in the vitreous cavity (Stage 3). The final stage was to evaluate the toxic effect of the quantum dot solution in its pure form, as well as in combination with antibiotics (ceftazidime and vancomycin) when administered intravitreally on an animal model. As a result of the study, quantum dots were synthesized and a solution based on them was obtained for introduction into the vitreous cavity. Based on the testing of the animal model (rabbits), a safe dose of the solution was determined, as well as the possibility of its use in combination with antibiotics.

Background: The electroretinogram is a clinical test used to assess the function of the photoreceptors and retinal circuits of various cells in the eye, with the recorded waveform being the result of the summated response of neural generators across the retina. Methods: The present investigation involved an analysis of the electroretinogram waveform in both the time and time–frequency domains through the utilization of the discrete wavelet transform and continuous wavelet transform techniques. The primary aim of this study was to monitor and evaluate the effects of treatment in a New Zealand rabbit model of endophthalmitis via electroretinogram waveform analysis and to compare these with normal human electroretinograms. Results: The wavelet scalograms were analyzed using various mother wavelets, including the Daubechies, Ricker, Wavelet Biorthogonal 3.1 (bior3.1), Morlet, Haar, and Gaussian wavelets. Distinctive variances were identified in the wavelet scalograms between rabbit and human electroretinograms. The wavelet scalograms in the rabbit model of endophthalmitis showed recovery with treatment in parallel with the time-domain features. Conclusions: The study compared adult, child, and rabbit electroretinogram responses using DWT and CWT, finding that adult signals had higher power than child signals, and that rabbit signals showed differences in the a-wave and b-wave depending on the type of response tested, while the Haar wavelet was found to be superior in visualizing frequency components in electrophysiological signals for following the treatment of endophthalmitis and may give additional outcome measures for the management of retinal disease.