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Based on the available literature data, the article discusses the prevalence of various forms of damage of the peripheral nervous system in COVID-19 and in the post-COVID period. Information about the clinical features and the course of individual cranial neuropathies, chronic dysimmune neuropathies, Guillain-Barré syndrome, drug-induced neuropathies, fine fiber neuropathy, myasthenia gravis and polyneuropathy of critical conditions was systemized in the context of coronavirus infection. SARS-CoV-2 can trigger various stages of pathogenesis, including neuroimmune ones, which cause long-term consequences of COVID-19, including those associated with the damage of the peripheral nervous system. Awareness of COVID-19-associated pathological conditions will allow assessment of the possible risks of damage of the peripheral nervous system, recognize them at early stages and develop more effective approaches for treatment.В статье на основе имеющихся данных публикаций литературы рассматривается распространенность различных форм поражения периферической нервной системы при COVID-19 и в постковидном периоде. Систематизированы сведения об особенностях клинической картины и течения отдельных краниальных нейропатий, хронических дизиммунных нейропатий, синдрома Гийена—Барре, лекарственных нейропатий, нейропатии тонких волокон, миастении и полинейропатии критических состояний в контексте коронавирусной инфекции. Вирус SARS-CoV-2 может запускать различные звенья патогенеза, в том числе нейроиммунные, что обусловливает долгосрочные последствия COVID-19, в том числе связанные с поражением периферической нервной системы. Осведомленность о COVID-19-ассоциированных патологических состояниях позволит проводить оценку возможных рисков возникновения поражений периферической нервной системы, распознать их на ранних стадиях и разработать более эффективные стратегии лечения данных заболеваний.

The company's ability to offer competitive products to the market on time is a key success factor, and more and more modern Russian managers are successfully implementing integrated approaches to the formation and management of competitiveness at all stages of the life cycle. However, at the moment, both in business practice and in the economic literature, there is no single approach to the definition of the concept of "competitiveness", a single methodology for evaluation has not been developed. The conducted content analysis allowed us to identify the unconditional properties of competitive products – the ability to surpass the competitor's products in terms of price and nonprice parameters and simultaneously meet the leading and currently relevant consumer needs at each stage of the product life cycle. When implementing the competitiveness assessment procedure, it is necessary to pay attention to the regulation of all the main stages, depending on the objectives of the assessment. Taking into account the characteristics of the product, the researcher needs to solve a number of ambiguous questions: to form a base for comparison, to choose the comparison parameters, and the evaluation method. The article identifies the risks that can distort the results of the study, highlights the key shortcomings of the most common assessment methods. As promising methods, the author suggests adapting the method of analyzing hierarchies, functionalcost analysis, and structuring quality functions.

Безусловно, благотворительная деятельность является эффективным механизмом реализации социальных задач, принося пользу как обществу, так и бизнесу. В настоящее время существует проблема, связанная с выявлением неявных выгод компании при реализации благотворительных проектов, отсутствует подходящая методика оценки воздействия филантропии на стоимость нематериальных активов компании. Благотворительная деятельность способна оказывать косвенное положительное воздействие на бизнес, которое, на первый взгляд, сложно измерить. Целью данного исследования является выявление влияния благотворительной деятельности на финансовые показатели компании. Автором проанализированы факторы, определяющие неявные выгоды компаний при реализации благотворительной деятельности, предложен комплексный подход к оценке нематериальных активов, изменяющихся в зависимости от объемов и частоты пожертвований. В исследовании выявлена взаимосвязь между благотворительной активностью, деловой репутацией предприятия, уровнем лояльности клиентов и показателями экономической эффективности, рассмотрены аспекты эффективной стратегической модели корпоративной филантропии. Практическая значимость статьи заключается в возможности использования предложенной методики комплексной оценки для выявления оптимальной и наиболее эффективной методики повышения имиджа организации за счёт использования таких инструментов, как благотворительная деятельность, импакт-инвестирование, спонсорская поддержка и рекламные кампании.

Формирование фонда целевого капитала является одним из перспективных направлений финансирования деятельности учреждений культуры в вопросе привлечения дополнительных внебюджетных средств. Комплексный подход выбора управляющей компании с целью размещения активов эндаумент-фонда в инвестиционной среде является важнейшей задачей в аспекте эффективного управления некоммерческой организацией. От правильного выбора управляющей компании зависит не только ежегодный уровень доходности, но и минимизация рисков, связанных с сохранением фонда целевого капитала. Целью исследования является разработка методики выбора управляющей компании. При проведении исследований использовался метод сравнений, приемы экономического анализа. В статье приводятся актуальные данные о состоянии рынка фондов целевого капитала, задействованных в сфере культуры. Автор применил сравнительный метод исследования при определении эффективности управления эндаумент-фондами. Автором был проведен анализ отчетных данных о результатах деятельности управляющих компаний, на примере государственного музея «Эрмитаж» в исследовании проанализированы среднегодовые показатели доходности активов, среди 26 управляющих компаний при помощи разработанной методики была выбрана одна управляющая компания, представлены теоретические выводы и сформулированы предложения на тему стратегического подхода в выборе управляющей компании.

The project presents fundamental research on the development of concept and basic components of physical circuit based on optoelectronic elements (neuromorphic generators, memristors, optical fibers). This network can replace some functions of brain's neural networks (such as memory) through adaptive stimulation of neural interfaces at the cellular and cellular networks level. Developing learning system will perform the electrical stimulation of brain areas based on the neural activity recorded and will include electronic devices for recording and processing signals. In addition, this system will include electronic devices for generating electrical stimuli based on hardware models of neurons and memristive devices. The basic idea is to integrate an artificial network with living microcircuits of the brain. The artificial network is capable of adaptively generating electrical output signals and can stimulate a given area of the brain according to the recorded pattern of input signals. We suppose that such a network will be able to reproduce the functions of brain systems, based on the use of learning algorithms. It can be used to expand the functionality of these brain systems and to replace lost functions in pathology or trauma.

We present a novel integration technology for replacing damaged microcircuits in the rat brain with electronic neuronal networks. This technology will allow simulating important brain functions, such as memory, through the adaptive stimulating effects of neural interfaces at cellular and neuronal network levels. The proposed system includes electronic devices to register and process neuronal signals and to adaptively stimulate damaged brain areas according to the online algorithm decoding the registered neuronal activity. The stimulation algorithm is implemented in hardware neural network with memristive connections that allows both network learning and adaptive re-learning.The basic idea is to develop components of hardware neural network with memristive connections for adaptive generation of electrical signals to stimulate particular brain areas. Moreover, the uniqueness of the system is adaptive closed-loop connection between two hippocampal neuronal networks. Such a system is very promising for restoring functionality of damaged areas in the human brain to replace lost functions in patients with brain pathologies or trauma.

Autonomic dysfunction is frequently observed in people with epilepsy. Ictal and postictal dysautonomia is not only manifestation of autonomic seizures, but could be a life threatening condition in some cases and contribute to sudden unexpected death (SUDEP). Interictal decrease of autonomic activity is associated with duration and severity of epilepsy, it is the most prominent in focal and drug-resistant epilepsy. Progress in our understanding of the underlying mechanisms, development of the autonomic assessment methods, and its integration in novel technical solutions for seizure detection will improve the quality of care for people with epilepsy.Вегетативная дисфункция часто присутствует у пациентов с эпилепсией. Иктальные и постиктальные вегетативные нарушения не только представляют собой проявления эпилептических приступов, но в ряде случаев являются жизнеугрожающим состоянием и связаны с феноменом внезапной смерти пациентов с эпилепсией (sudden unexpected death in epilepsy, SUDEP). В интериктальном периоде субклиническое снижение вегетативной активности, считающееся предиктором развития сердечно-сосудистых расстройств, ассоциировано с длительностью и тяжестью течения эпилепсии, оно наиболее выражено при расположении очага в височной доле и наличии фармакорезистентности. Дальнейшее изучение патогенеза вегетативной дисфункции, совершенствование методов оценки вегетативной регуляции организма и их интеграция в современные технологические решения для автоматизированной регистрации приступов могут открыть новые возможности улучшения качества ведения пациентов с эпилепсией.

We propose a hybrid memristve neuromorphic system for stimulating hippocampus regions bypassing damaged areas. Synaptic plasticity properties of the system allow close-loop adaptive control of neural dynamics. We implement the simplest version of this system which consists of two neuron-like generators coupled by a memristive device, and two fiber-optic channels to transmit signals from the generators directly to living cells to stimulate hippocampus regions. The adaptive stimulation nature of the neural cells is provided by a stochastic response of the self-learning memristive device to the signal of the neuron-like generator. A biological model of impaired functioning of the perforating pathway in the rat hippocampus is implemented by damaging the CA3 region, on the base of the electrophysiological signal changes in normal and pathological conditions. The proposed adaptive stimulation technology demonstrates the possibility of restoring the functionality of the perforating pathway by introducing the neuromorphic system into the hippocampus to replace lost areas.

In the current study, biochemical abnormalities occurring in the body of children with cancer in sepsis, as well as their relationship with the new marker of sepsis and phagocytosis by presepsin, are considered. A survey enrolled 112 children who were treated at the N.N. Blokhin National Medical Research Center of Oncology. Differences in medians of a number of biochemical parameters in groups of patients who survived and died of sepsis were revealed.

The mechanisms that underlie the early loss of the male reproductive function are still unknown. Therefore, investigation of this problem is an important task. The medial preoptic nucleus takes part in the regulation of sexual behavior; however, the role of glycine transmission in this nucleus has not yet been studied. Our study focuses on these questions.

We propose an optoelectronic system for stimulation of living neurons. The system consists of an electronic circuit based on the FitzHugh-Nagumo model, an optical fiber, and a photoelectrical converter. We used this system for electrical stimulation of hippocampal living neurons in acute hippocampal brain slices (350-μm thick) obtained from a 20-28 days old C57BL/6 mouse or a Wistar rat. The main advantage of our system over other similar stimulators is that it contains an optical fiber for signal transmission instead of metallic wires. The fiber is placed between the electronic circuit and stimulated neurons and provides galvanic isolation from external electrical and magnetic fields. The use of the optical fiber allows avoiding electromagnetic noise and current flows which could affect metallic wires. Furthermore, it gives us the possibility to simulate "synaptic plasticity" by adaptive signal transfer through optical fiber. The proposed optoelectronic system (hybrid neural circuit) provides a very high efficiency in stimulating hippocampus neurons and can be used for restoring brain activity in particular regions or replacing brain parts (neuroprosthetics) damaged due to a trauma or neurodegenerative diseases.

Astrocytes are involved in maintenance of synaptic microenvironment by glutamate uptake and K+ clearance. These processes are associated with net charge transfer across the membrane and therefore can be recorded as glutamate transporter (IGluT) and K+ (IK) currents. It has been previously shown that the blockade of IK with BaCl2 enhances the IGluT. Here we show that activity-dependent facilitation (5 stimuli at 50 Hz) of IGluT was not significantly different in BaCl2 compared to facilitation of IGluT isolated by post-hoc subtraction of IK. Nevertheless, BaCl2 abolished the activity-dependent prolongation of τdecay, which was observed for IGluT isolated by post-hoc subtraction of IK. This finding suggests that activity-dependent accumulation of extracellular K+ ([K+]o) causes astrocytic depolarization, which is responsible for the increase in τdecay of IGluT. The blockade of inward rectifying K+ channels (Kir) with BaCl2 makes astrocytic membrane potential insensitive to [K+]o elevation and thus abolishes this increase. Blockade of IGluT with glutamate transporter blocker, DL-threo-β-benzyloxyaspartic acid (TBOA) did not significantly affect the amplitude of IK but decreased its τdecay. However, activity dependent facilitations of both amplitude and τdecay of IK were larger in TBOA, than in the control conditions. We suggest that activity-dependent accumulation of extracellular glutamate can enhance release of K+. Thus activity-dependent changes in [K+]o can affect glutamate dwell-time in the synaptic cleft, and vice versa, extracellular glutamate accumulation can affect [K+]o time-course. Our finding is important for understanding of the astrocytic mechanisms in glutamate excitotoxicity and in diseases related to disruption of K+ homeostasis (e.g. stroke, migraine, and epilepsy).

The report presents the results of research and development on cementation technology of liquid radioactive waste (LRW) generated in spent nuclear fuel reprocessing in Experimental Demonstration Center (EDC) at the Mountain Chemical Combine, Russian Federation.

The medial preoptic nucleus is critically involved in the social type of behavior regulation, such as parental behaviour, social recognition, sexual behaviour, ect.. A big amount of studies are focused on the role of glutamate, GABA, serotonin, and dopamine systems of medial preoptic area (mPOA) in the social types of behaviour regulation. However, the role of glycinergic system in this nucleus has not been investigated.

Цель исследования изучить влияние динамики ионных концентраций во время воздействия нейрональной активности на кальциевую активность в астроцитах гиппокампа крыс. Материалы и методы. Исследования проводили на переживающих срезах гиппокампа крыс линии Wistar возрастом 15-18 дней с использованием метода функционального кальциевого имиджинга. Результаты. Установлено, что при активации метаботропных рецепторов глутамата в астроцитах увеличиваются частота и длительность кальциевых осцилляций; при повышении внеклеточной концентрации кальция увеличивается только частота, длительность не изменяется; при повышении концентрации калия частота значительно увеличивается, длительность снижается. Заключение. Нейрональная активность, приводя к локальным изменениям ионных концентраций, может оказывать влияние на астроцитарную кальциевую сигнализацию, формируя при этом дополнительную систему обратной связи, регулирующую нормальное функционирование нейрон-глиальных сетей. Полученные данные указывают на комплексную природу воздействия активности нейронов на астроциты, которая не может рассматриваться только в контексте рецепторной передачи сигналов.The aim of the study was to understand the effect of alterations in local ionic concentrations due to neuronal activity on calcium activity in astrocytes. Materials and Methods. In this study we investigated astrocytic calcium dynamics using confocal microscopy on hippocampal slices from Wistar rats P15-18. Results. Here we demonstrated that activation of metabotropic glutamate receptors on astrocytes led to an increase of the frequency and duration of calcium events. Elevations of the extracellular calcium concentration did not change the frequency and the duration. Elevations of the extracellular potassium concentration increased the frequency and reduced the duration of calcium events. Conclusions. Neuronal activity causing alterations in local ionic concentrations might affect calcium activity in astrocytes, creating a feedback loop, controlling functioning of neuron-glia networks. These data indicate the complex nature of the effects, which modulate the interplay between neurons and astrocytes that cannot be considered only in the context of a receptor signaling.

The aim of the investigation was to study the astroglia functional activity in hippocampal slices of the rat at different postnatal development stages by modeling metabolic changes in the brain. Materials and Methods. The study was carried out on hippocampal slices of Wistar rats of three age groups: postnatal days 5–10, 10–20, and more than 20 days of animal postnatal development using a functional calcium imaging method. Results. In early developmental stages, normal astroglial calcium activity was found to require additional energy substrates. Changing the brain metabolic state at low temperature had no significant effect on astrocyte calcium activity in all postnatal periods under study. Conclusion. The study of astrocyte calcium dynamics in different periods of postnatal development can be used as a method to assess functional activity of glial systems when modeling brain metabolic disorders.

Summary form only given, as follows. In our previous research it is shown that regimes with high specific power (about 10/sup 5/ W/cm/sup 3/) put in anode parts of discharge can be carried out. A generator of microplasma jet has been designed and constructed on the basis of results obtained before. A generator was tested in helium. Voltage of discharge was 700 V at a discharge current equal 15 mA. Consumption of helium in the experiments was 1.1/mm. The power of microplasma jet was 1.6 W. Diameter of microplasmotron exit opening was 0.8 mm and radius of curvature of a pointed anode -8 mkm. Microplasma jet has following parameters length -20 mm, diameter - about 0.1 mm. This paper reports about characteristics of microplasma flow (volt-ampere characteristic, integral power of plasma jet and local values of mass average temperature of plasma as well). Spectra of plasma radiation are registrated. Applications of microplasma generator such as medicine and electronic facilities technology are discussed.