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Assessment of patients with intracranial aneurysms in the late postoperative period consists of both determining structural changes in computed tomography (CT) and the neurological and cognitive status of the patient. Meantime, the topic of the relationship between structural pathology in CT and cognitive impairment has not been suffi ciently disclosed.Objective: to determine CT, functional and cognitive outcomes in the long-term period of surgical treatment of cerebral aneurysms.Material and methods. The data of CT angiography of 49 patients operated on for intracranial aneurysms were analyzed. 39 patients were examined neurologically for 2.3 years using a range of rating scales.Results. The residual part of the aneurysm after surgery was found in 50% of patients with complex aneurysms, more often in patients with PMA-PSA aneurysms. The connection between the method of surgery and the preserved cervical part with structural changes in the brain and the development of cognitive impairment in the late postoperative period has not been proven.Conclusion. CT angiography preoperatively makes it possible to identify a group of complex aneurysms with a high risk of preservation of the cervical part and the development of brain structural changes. The predictors of the development of ischemic changes in the brain, hydrocephalus, and cognitive dysfunctions was the advanced age of patients, the duration of the operation, and a history of hypertension.

Aim. To describe the experience of using augmented reality system in abdominal surgery at one clinical center.Materials and methods. In 2021–2022, five patients underwent laparoscopy with augmented reality technology. The interventions included echinococcectomy with resection of IV, V, VI liver segments, pancreaticoduodenal resection for pancreatic head cancer, excision of mesostenium cyst, resection of pancreas body and tail for neuroendocrine tumor.Results. Application of 3D models requires putting on glasses, scaling and setting a model on the screen image, which sometimes prolonged surgery time to 25 minutes. In a number of operations the use of augmented reality navigated the surgeon when working near vascular structures. After looking through the AR model, a surgeon felt more confident in terms of individual anatomy.Conclusion. Augmented reality can become a reliable and promising tool in abdominal surgery. However, further technological development in augmented reality systems is needed to increase their performance.

Introduction. Spinal cord injury is a debilitating traumatic event in central nervous system resulting in tissue destruction and severe neurological deficit development. Preclinical assessment of quantitative lesion area parameters (e. g. structure and volume) is critical for subsequent evaluation of neuroprotective and / or neuroregenerative therapy efficiency. Current methods for parameter calculation require manual limitation of the interested area (region of interest, RoI). This process is tedious and often not precise enough.Study objective is to develop and implement software for automated assessment of volume and structure of posttraumatic spinal cord lesion using extra-high-field MRI 7.0 Tesla and to compare methods preciseness with the current manual techniques.Study design. Ten rat models of acute severe spinal cord contusion injury were used including female Sprague–Dawley animals weighting 250–350 gr. MRI imaging was performed in 1 day postoperative and then 4 times with interval (1 week). Study was prospective open-label uncontrolled comparative.Materials and methods. Standard spinal cord contusion injury model was used. Anesthetized animals underwent laminectomy at level Th9–Th10 vertebrae followed by “weight drop” injury technique application: 10 g weight with 2 mm pin diameter dropped from 25 mm height. Software was developed using Microsoft Visual Studio 2017 environment and programming language C#. Statistical analysis was performed using IBM SPSS Statistics 21.0 software.Results. We developed and patented specialized software Spinal cavity Searcher realizing the algorithm of T2‑weighted images (T2‑WI) analysis based on image bynarization and Freeman chain code. This algorithm supports calculation of spinal cord posttraumatic lesion parameters in a half-automatic manner. Results of this algorithm application were comparable to results of manual calculation: no statistical difference were observed between two values.Conclusion. Current method of spinal cord injury volume and structure quantitative assessment simplifies the calculation procedure due to automatization of RoI limitation comparing to manual technique. The level of preciseness is comparable in both methods.Clinical relevance. The developed algorithm optimizes the process of non-invasive control of the performed treatment efficiency according to 7.0 Tesla MRI data.

Epilepsy surgery is effective in 30–85% of patients with drug-resistant epilepsy. However, risk factors associated with favorable and unfavorable outcomes of epilepsy surgery need to be further evaluated. We present the outcome of the large epilepsy surgery cohort in Russian Federation.Purpose: evaluation of risk factors of favorable and unfavorable long-term outcomes in the Russian cohort of drugresistant patients with epilepsy.Material and methods. Three hundred and eight patients with structural drug-resistant epilepsy were operated by the neurosurgery team of Moscow State University of Medicine and Dentistry. Presurgical investigations and surgeries were performed by this team between 01.01.2014 and 31.12.2020. All patients underwent neurological and neuropsychological evaluation, seizure semiology assessment, neuroimaging and neurophysiological examination. Histological analysis of resected tissues was performed. Results of surgery were assessed according to J. Engel (1993) at 6, 12, 24, 48 and 60 months after surgery. Risk factors, associated with favorable (Engel I–II) and unfavorable (Engel III–IV) outcomes were evaluated.Results. Underwent 308 primary resection procedures, placement of a vagus nerve stimulator were in 41 patients, 9 patients have been repeated by resection procedures and 8 — underwent radiosurgical treatment. 256 (83%) patients were MR-positive, 53 (17%) — MR-negative. Temporal lesions were revealed in 186 (60%) patients, extratemporal — in 8 (3%), bilateral temporal — in 15 (5%), combination of temporal and extra-temporal — in 81 (26%), multifocal — in 16 (5%), generalized form in 2 (1%). In 12 months after surgery there were favorable outcomes (Engel I + II) in 85% of patients (n = 148), in 24 months — 70% (n = 127). In patients with MRI positive and negative lesions the result of surgery after 12 months was comparable. Postoperative complications were diagnosed in 6 (1.9%) patients, there were no mortality. Temporal plus epilepsy (p = 0.009), multifocal (p = 0.008) and bilateral lesions (p = 0.006) were the most significant risk factors of unfavorable surgery outcomes.Conclusion. The presented results confirm the efficiency of surgical treatment of drug-resistant epilepsy. Temporal plus form epilepsy, multifocal and bilateral lesions were the most significant risk factors of unfavorable surgery outcomes.

Purpose. To determine the frequency and risk factors for the development of internal spontaneous internal hemorrhage and clinical manifestations in patients with COVID-19 undergoing inpatient treatment. Material and methods. In the period from10.20 till 06.2021, 28 cases of spontaneous internal hemorrhage in patients with confi rmed COVID-19 complicated by bilateral interstitial polysegmental pneumonia were analyzed at the COVID-19 Clinical Center of Moscow State Medical University named after Evdokimov. Anamnesis, age, gender, objective examination data, concomitant diseases, laboratory blood counts, CT results, soft tissue ultrasound, treatment regimens, characteristics of hematomas (volume, localization) and hospitalization outcomes were analyzed. Results. Summarizing the results of our own observations, a low number (no more than 1%) of hemorrhagic complications in patients with coronavirus infection were noted. In more than half of the patients, spontaneous internal hemorrhages were detected during the 2nd–3rd weeks of treatment, for 17.4 ± 2.7 days on average. The main risk factors for the development of internal spontaneous hemorrhage with the formation of hematomas in patients with COVID-19 should be considered old age, female sex, and the presence of hypertension, diabetes mellitus, and anticoagulant therapy. Hemorrhages of any localization and intensity, both isolated and combined, can develop regardless of the severity of lung damage and respiratory failure. In case of a decrease in the level of hemoglobin in the dynamics of treatment, fi brinogen, hypotension, the appearance of pain syndromes of various localization (against the background of a decrease in C-reactive protein (CRP), and an increase in leukocytes in the blood), emergency computed tomography (CT) is indicated for timely diagnosis of hemorrhage and the formation of hematomas. Surgical treatment is indicated for hemodynamically stable patients with large-volume soft tissue hematomas (more than 500 ml) with signs of suppuration according to ultrasound or CT. The prescription of anticoagulants and antiplatelet agents, regardless of the dosage, can lead to hemorrhagic complications, which requires constant monitoring of coagulogram parameters in order to correct the dose.

We consider a mathematical model of the treatment of psoriasis on a finite time interval. The model consists of three nonlinear differential equations describing the interrelationships between the concentrations of T-lymphocytes, keratinocytes, and dendritic cells. The model incorporates two bounded timedependent control functions, one describing the suppression of the interaction between T-lymphocytes and keratinocytes and the other the suppression of the interaction between T-lymphocytes and dendritic cells by medication. For this model, we minimize the weighted sum of the total keratinocyte concentration and the total cost of treatment. This weighted sum is expressed as an integral over the sum of the squared controls. Pontryagin’s maximum principle is applied to find the properties of the optimal controls in this problem. The specific controls are determined for various parameter values in the BOCOP-2.0.5 program environment. The numerical results are discussed.

The local dynamics of an optoelectronic oscillator model characterized with feedback delay is investigated. In the neighborhood of the zero equilibrium state, normalized equations are constructed, which are boundary value problems depending on the continuumal parameter. Such problems are used to determine the asymptotic solutions of the original nonlinear system, mainly the frequencies and amplitudes of the components, in the form of a combination of slow and fast oscillations.

We use the methods of asymptotic analysis to obtain finite-dimensional maps, whose dynamics determines the dynamics of relaxation oscillations in a laser model with optoelectronic feedback. The coexistence of cycles and chaotic attractors is demonstrated. Switching of spiking regimes by pulsed disturbance of pumping in a certain oscillation phase is discussed.

The local dynamics of a well-known model of an optoelectronic oscillator with delayed feedback is studied. In a neighborhood of zero equilibrium, normalized equations are constructed which are boundary value problems depending on a continual parameter. Asymptotic solutions of the original nonlinear system in the form of a combination of slow and fast oscillations are obtained by solving the boundary value problems. The frequencies and amplitudes of the components of these solutions are determined.

We consider the dynamics of an electro-optic oscillator described by a system of differential equations with delay. An essential feature of this model is that one of the derivatives is multiplied by a small parameter, which allows us to draw conclusions about the action of processes with rates of different orders. The local dynamics of a singularly perturbed system near a zero steady state is analyzed. When values of the parameters are close to critical, the characteristic equation of the linearized problem has an asymptotically large number of roots with close-to-zero real parts. The bifurcations taking place in the system are studied by constructing special normalized equations for slow amplitudes, which describe the behavior of close-to-zero solutions of the initial problem. An important feature of these equations is that they do not depend on the small parameter. The structure of roots of the characteristic equation and the order of supercriticality determine the normal form, which can be represented by a partial differential equation. The “fast” time, for which periodicity conditions are fulfilled, acts as a “spatial” variable. The high sensitivity of dynamic properties of normalized equations to the change of a small parameter is noted, which is a sign of a possible unlimited process of direct and inverse bifurcations. Also, the obtained equations exhibit multistability of solutions.

Aim To study the effect of regular drug therapy for cardiovascular and other diseases preceding the COVID-19 infection on severity and outcome of COVID-19 based on data of the ACTIVE (Analysis of dynamics of Comorbidities in paTIents who surVived SARS-CoV-2 infEction) registry.Material and methods The ACTIVE registry was created at the initiative of the Eurasian Association of Therapists. The registry includes 5 808 male and female patients diagnosed with COVID-19 treated in a hospital or at home with a due protection of patients’ privacy (data of nasal and throat smears; antibody titer; typical CT imaging features). The register territory included 7 countries: the Russian Federation, the Republic of Armenia, the Republic of Belarus, the Republic of Kazakhstan, the Kyrgyz Republic, the Republic of Moldova, and the Republic of Uzbekistan. The registry design: a closed, multicenter registry with two nonoverlapping arms (outpatient arm and in-patient arm). The registry scheduled 6 visits, 3 in-person visits during the acute period and 3 virtual visits (telephone calls) at 3, 6, and 12 mos. Patient enrollment started on June 29, 2020 and was completed on October 29, 2020. The registry completion is scheduled for October 29, 2022. The registry ID: ClinicalTrials.gov: NCT04492384. In this fragment of the study of registry data, the work group analyzed the effect of therapy for comorbidities at baseline on severity and outcomes of the novel coronavirus infection. The study population included only the patients who took their medicines on a regular basis while the comparison population consisted of noncompliant patients (irregular drug intake or not taking drugs at all despite indications for the treatment).ResultsThe analysis of the ACTIVE registry database included 5808 patients. The vast majority of patients with COVID-19 had comorbidities with prevalence of cardiovascular diseases. Medicines used for the treatment of COVID-19 comorbidities influenced the course of the infectious disease in different ways. A lower risk of fatal outcome was associated with the statin treatment in patients with ischemic heart disease (IHD); with angiotensin-converting enzyme inhibitors (ACEI)/angiotensin receptor antagonists and with beta-blockers in patients with IHD, arterial hypertension, chronic heart failure (CHF), and atrial fibrillation; with oral anticoagulants (OAC), primarily direct OAC, clopidogrel/prasugrel/ticagrelor in patients with IHD; with oral antihyperglycemic therapy in patients with type 2 diabetes mellitus (DM); and with long-acting insulins in patients with type 1 DM. A higher risk of fatal outcome was associated with the spironolactone treatment in patients with CHF and with inhaled corticosteroids (iCS) in patients with chronic obstructive pulmonary disease (COPD).Conclusion In the epoch of COVID-19 pandemic, a lower risk of severe course of the coronavirus infection was observed for patients with chronic noninfectious comorbidities highly compliant with the base treatment of the comorbidity.

This study is aimed at the comparison of the process of manual and robotic positioning of the electrode performing radiofrequency ablation under the control of a surgical navigation system. The main hypothesis of this experiment was that the use of a collaborative manipulator (KUKA iiwa) will allow to position the active part of the electrode relative to the center of the tumor more accurately and from the first attempt. We also monitor the stability of the electrode′s velocity during insertion and consider some advantages in ergonomics using the robotic manipulator. We use three more criteria to compare the surgeon's and robotic performance, unlike other studies, where only the target point's accuracy criterion is observed. The main idea is to examine the movement parameters of the electrode that can lead to potential patient trauma. Sphere-shaped tumor phantoms measuring 8 mm in diameter were filled with contrast and inserted in bovine livers. 10 livers were used for the robotic experiment and an equal quantity for manual surgery. The livers were encased in silicone phantoms designed to imitate the liver position in a real patient's abdominal cavity. Analysis of CT data gave the opportunity to find the entry and the target point for each tumor phantom. This data was loaded into a surgical navigation system that was used to track and record the position of the RF-electrode during the operation for further analysis. The standard deviation of points from the programmed linear trajectory totaled in the average 0.3 mm for the robotic experiment and 2.33 mm for the manual operation with a maximum deviation of 0.55 mm and 7.99 mm respectively. Standard deviation from the target point was 2.69 mm for the collaborative method and 2.49 mm for the manual method. The average velocity was 2.97 mm/s for the manipulator and 3.12 mm/s for the manual method, but the standard deviation of the velocity relative to the value of the average velocity was 0.66 mm/s and 3.05 mm/s respectively. Thus, in two criteria out of three, the manipulator is superior to the surgeon, and equality is established in one. Surgeons also noticed advantages in ergonomics performing the procedure using the manipulator. This experiment was produced as part of the work on the developing of a robotic multifunctional surgical complex. We can confirm the potential advantages of using collaborative robotic manipulators for minimally invasive surgery in case of practice for cancer treatment.

The present paper researches the matter of human impact on atmosphere that is currently the focus object of specialists and environment researchers all over the World. And it is not a coincidence as the most significant environmental problems of today - the “greenhouse effect”, ozone layer depletion, acid rains are in relation with the anthropogenic pollution of atmosphere. The paper also touches upon the impact of atmosphere pollution on human health and environment. There are considered various means of pollution – from direct and immediate threats (smog, etc.) to slow and gradual destruction of various organism life support systems. In many cases air pollution erodes ecosystem structural components to a degree when regulatory processes are unable to restore the initial state that causes homeostasis mechanism failure.

The study objective is to analyze the results of surgical treatment of patients with endocrine ophthalmopathy using minimally invasive transorbital approaches and intraoperative frameless neuronavigation.Materials and methods. The study was based on the results of examination and surgical treatment of 9 patients with endocrine ophthalmopathy (17 orbits) in the period from 2015 to 2017. At the first stage the preoperative computed tomography images of the orbits was imported into the navigation software program, and then the area of the proposed resection of the orbit walls was marked. Further, in the operating room, the patient head position was registered in the navigation system. To perform bone decompression of the orbit and lipectomy, we used preseptal, transcaruncular and lateral retrocanthal approaches. These approaches are transconjunctival and do not leave postoperative scars. Upon completion of the orbitotomy, its accuracy and dimensions were determined by the intraoperative pointer of the neuronavigation system.Results. The postoperative period was uneventful. In all patients, according to clinical examination and computed tomography, good cosmetic and functional results were achieved. Only 1 patient developed a simblypharon after transconjunctival access, which required additional intervention to reconstruct the lower eyelid. There were no other complications of surgical treatment. The minimum degree of regression of exophthalmos was 3 mm, the maximum 7 mm. Diplopia completely regressed in 2 patients. The observation period was 6 months.Conclusion. Minimally invasive transorbital approaches allow the transconjunctival view of all orbital walls to perform decompression of the orbit and lipectomy without cutaneous incisions, to achieve good cosmetic and functional results. The intraoperative use of the neuronavigation system ensures the bone decompression of the orbit in full.

We consider electro-optic oscillator model which is described by a system of the delay differential equations (DDE). The essential feature of this model is a small parameter in front of a derivative that allows us to draw a conclusion about the action of processes with different order velocities. We analyse the local dynamics of a singularly perturbed system in the vicinity of the zero steady state. The characteristic equation of the linearized problem has an asymptotically large number of roots with close to zero real parts while the parameters are close to critical values. To study the existent bifurcations in the system, we use the method of the behaviour constructing special normalized equations for slow amplitudes which describe of close to zero original problem solutions. The important feature of these equations is the fact that they do not depend on the small parameter. The root structure of characteristic equation and the supercriticality order define the kind of the normal form which can be represented as a partial differential equation (PDE). The role of the ”space” variable is performed by ”fast” time which satisfies periodicity conditions. We note fast response of dynamic features of normalized equations to small parameter fluctuation that is the sign of a possible unlimited process of direct and inverse bifurcations. Also, some obtained equations possess the multistability feature.

We derive asymptotically discrete mappings which determine the dynamics of relaxation spikes in a model of laser with optoelectronic feedback in the pump circuit. The time delay in the feedback path varies periodically. Bifurcations of mapping’s attractors correspond to the appearance of quasi-periodic and chaotic spiking with special properties.

The problem about local dynamics of the logistic equation with a rapidly oscillating timeperiodic piecewise constant coefficient of delay has been considered. It has been shown that the averaged equation is a logistic equation with two delays. A stability criterion for equilibrium points has been obtained. The dynamical properties of the original equation are considered provided that the critical case of the equilibrium point stability problem has been implemented. It has been found that an increase of delay coefficient oscillation frequency may lead to an unlimited process of steady-mode birth and death.

The paper touches upon the environmental issues of the modern civilization and the new technologies of waste recycling. The paper also dwells upon waste-free production where all the raw materials are transformed into products which is, at the same time, optimized in terms of process, economic, social and environmental criteria. There are also given the figures of increase of garbage volume in various countries including Russia. There are stated the most dangerous products of decomposition of plastic. In the article there are also considered the modern technologies of waste recycling which is the most prospective way to solve the issue of urban landfills. There are given the examples of recycling of combustible waste, rotting waste, medical waste and old cars without harming the environment.

The article discusses the major principles of innovation processes effective management. In the article there are defined the main participants of innovation process and functions of innovation process management. There is given a general diagram of innovation process management. Also there is stated that effective management of innovation processes is closely connected with combination of all the system elements in a company activity. Creation and wide distribution of new products and services becomes a determining factor of a company growth and development, increase of production, employment rate and of investments attraction. Innovative development is the most important factor capable of increasing company competitiveness. This factor is based on various kinds of activity such as scientific, social, production or financial activity. Innovations are aimed at significant increase of technical and economic efficiency of company activity.

Dynamics of laser with time-variable delayed feedback is analyzed in the neighborhood of the equilibrium. For the system, averaged over a rapidly variable, we obtain parameters at which the stationary state is stable. Stabilization of the stationary state due to modulation of the delay can be successful (unsuccessful) in domains adjacent to super (sub-) critical Hopf bifurcation boundaries. In a vicinity of the bifurcation points, stable and unstable periodic solutions are asymptotically described in dependence on the modulation frequency.

Dynamics of laser generation is considered on the base of single-mode rate equations with retarded argument. In the framework of local analysis, we determine continual sets of families of quasi-normal forms in the vicinity of the bifurcation parameter values. Their solutions imply the coexistence of a large number of steady oscillatory modes due to a large delay.

The search of molecular markers of metastasing and prognosis in prostate cancer remains an urgent task. In this study, we investigated the relationship of gene expression heparanase-1 (HPSE1) and D-glucuronil C5-epimerase (GLCE) with early disease relapse and metastasis of a 2,5−3 years after diagnosis. It was shown that the ratio of the expression levels of genes HPSE1/GLCE > 1 may serve as a prognostic relapse marker and trends of the tumour to metastasis. The data obtained suggest to use this option as a molecular marker for the diagnostics of metastatic process and the disease prognosis.

To evaluate the results of surgical treatment of patients with pharmacoresistant epilepsy.Examination and surgical treatment of 61 patients with pharmacoresistant forms of symptomatic epilepsy were performed from 01.01.14 to 01.05.16.The results confirmed the safety and efficacy of the surgical treatment of pharmacoresistant epilepsy. After 12 months, seizures were controlled in 69% of operated patients. The necessity of complex examination of all patients with pharmacoresistant epilepsy to make a decision about possible surgery is shown.Цель исследования. Оценить результаты хирургического лечения пациентов с фармакорезистентной эпилепсией. Материал и методы. За период с 01.01.14 по 01.05.16 было проведено обследование и хирургическое лечение 61 пациента с фармакорезистентной симптоматической формой эпилепсии. Результаты и заключение. Полученные результаты подтвердили безопасность и эффективность хирургического лечения указанных форм эпилепсии. По оценке через 12 мес контроль над приступами достигнут у 69% оперированных пациентов. Показана необходимость проведения комплексного обследования пациентов с фармакорезистентной формой эпилепсии для решения вопроса о возможном хирургическом лечении.Цель исследования. Оценить результаты хирургического лечения пациентов с фармакорезистентной эпилепсией. Материал и методы. За период с 01.01.14 по 01.05.16 было проведено обследование и хирургическое лечение 61 пациента с фармакорезистентной симптоматической формой эпилепсии. Результаты и заключение. Полученные результаты подтвердили безопасность и эффективность хирургического лечения указанных форм эпилепсии. По оценке через 12 мес контроль над приступами достигнут у 69% оперированных пациентов. Показана необходимость проведения комплексного обследования пациентов с фармакорезистентной формой эпилепсии для решения вопроса о возможном хирургическом лечении.

Low-frequency relaxation oscillations are well-known phenomenon in a laser without additional elements.

Synchronization and synergetic effects in coupled systems play a significant role in nature and artificial networks. They are under permanent investigation in view of various applications, see for example [55] and references therein. The detailed review of coupled lasers dynamics is presented in [56]. In this chapter, using above elaborated asymptotic method, we study relaxation oscillations in coupled systems whose elements are whole lasers and laser cavity modes. Both spiking and rectangular pulsing are considered in such systems.

In this chapter we consider dynamics of a laser with non-linear intracavity element, whose loss can be controlled by the density of the generated radiation. An example of such an element is Pockels cell. The scheme of the device is given in Fig. 4.1.

Lasing control by means of pumping current modulation via the feedback (FB) circuit has been first applied in laser diodes [46, 49, 50] and inCO2 lasers [47, 48]. Such optoelectronic control can stabilize the stationary generation as well as the generation of short pulses following in period correlated with the delay time in the FB circuit. The scheme of the device is given in Fig. 3.1.

The controllability problem is solved for a nonlinear system of three differential equations that simulates aerated biological wastewater treatment using the thermal metabolism of thermophilic aerobic bacteria. Properties of the phase variables of such a system, bounded and continuable to a given segment, are established. The corresponding attainability set is parameterized by the switching instants of piecewise-constant controls. Parameterization helps reduce the controllability problem for the relevant system to finite dimensional conditional minimization of the auxiliary function. The results from numerical calculations for the solution to the initial problem are given.