Mathematical Heritage of Sergey Naboko: Functional Models of Non-Self-Adjoint Operators

This is an overview of mathematical heritage of Sergey Naboko in the area of functional models of non-self-adjoint operators. It covers the works by Sergey in model construction, the analysis of absolutely continuous and singular spectra and the construction of the scattering theory in model terms.Comment: 14 pages. arXiv admin note: text overlap with arXiv:2204.0119

Confinement-controlled Water Engenders High Energy Density Electrochemical-double-layer Capacitance

The renewable energy sector critically needs low-cost and environmentally neutral energy storage solutions throughout the entire device life cycle. However, the limited performance of standard water-based electrochemical systems prevents their use in certain applications. Meanwhile, recent fundamental studies revealed dielectric anomalies of water near solid-liquid interfaces of carbon-based nanomaterials. In contrast to the bulk water properties, these anomalies of water under nano-confinement and in the presence of electric fields have not yet been understood and used. Here, we experimentally study the ability of the interfacial water layer to engender and store charge in electrochemical double-layer capacitance. We demonstrate the first prototype of a water-only membrane-electrode assembly. The prototype exhibits characteristics comparable to existing batteries and supercapacitors without using electrolytes as ionic carriers. The results provide the impetus for the development of high-energy-density electrochemical double-layer capacitors and open up other avenues for ecologically-neutral batteries, fuel cells, and nanofluidic devices

The Regulation of the Male Hypothalamic-Pituitary-Gonadal Axis and Testosterone Production by Adipokines

There is evidence that the mass and metabolic status of the adipose tissue that produces adipokines significantly affect the activity of the hypothalamic-pituitary-gonadal (HPG) axis and the synthesis of testosterone. This is due to the fact that adipokines, such as leptin, adiponectin, visfatin and resistin have an important role in the regulation of the male HPG axis and steroidogenesis in the testes. The regulation of the HPG axis by adipokines can be carried out both through the changes the plasma levels of adipokines (a systemic regulation) and through the changes in the expression and activity of adipokines in the pituitary and testes, the components of the HPG axis (an autonomous regulation). This review presents the comprehensive analysis of the involvement of leptin, adiponectin, resistin and visfatin in the regulation of the male HPG axis and the testosterone production, as well as of the possible mechanisms of this regulation. The role of adipokines in the dysregulation of the male reproductive system and the impaired steroidogenic activity in the testes in obesity and type 2 diabetes mellitus are also discussed

Data-driven control of micro-climate in buildings: an event-triggered reinforcement learning approach

Smart buildings have great potential for shaping an energy-efficient, sustainable, and more economic future for our planet as buildings account for approximately 40% of the global energy consumption. Future of the smart buildings lies in using sensory data for adaptive decision making and control that is currently gloomed by the key challenge of learning a good control policy in a short period of time in an online and continuing fashion. To tackle this challenge, an event-triggered -- as opposed to classic time-triggered -- paradigm, is proposed in which learning and control decisions are made when events occur and enough information is collected. Events are characterized by certain design conditions and they occur when the conditions are met, for instance, when a certain state threshold is reached. By systematically adjusting the time of learning and control decisions, the proposed framework can potentially reduce the variance in learning, and consequently, improve the control process. We formulate the micro-climate control problem based on semi-Markov decision processes that allow for variable-time state transitions and decision making. Using extended policy gradient theorems and temporal difference methods in a reinforcement learning set-up, we propose two learning algorithms for event-triggered control of micro-climate in buildings. We show the efficacy of our proposed approach via designing a smart learning thermostat that simultaneously optimizes energy consumption and occupants' comfort in a test building

Биохимические Показатели Крови Телят при Применении Галеновых Препаратов на Основе Биополимеров

The article discusses the issues about the effect of the energy coniferous flax stimulator on the blood chemistry values of calves. Every day for 14 days, bulls of two experimental groups (second and third groups) received the drug at the doses of 150 ml and 200 ml, respectively. The animals in the reference group did not receive the drug. When analyzing biochemical parameters, it has been established that the concentration of phosphorus in the blood of the experimental calves prior to the experiment was significantly below the normal level. The use of the drug has significantly increased the phosphorus level in the blood of the experimental calves. The AST/ALT ratio in the animals before the experiment exceeded the normal levels, whereas the use of the galenical preparation normalized this indicator. It has also been established that the drug provides the normalization of the calcium-phosphorus ratio.рассматриваются вопросы о влиянии препарата «Энергетический хвойно-льняной стимулятор» на биохимические показатели крови телят. Ежедневно на протяжении 14 суток бычки 2-х опытных групп (2-я и 3-я группы) получали препарат в дозах 150 мл и 200 мл соответственно. Животные контрольной группы препарат не получали. При анализе биохимических показателей установлено, что концентрация фосфора в крови подопытных телят до опыта была существенно ниже уровня нормы. Применение препарата достоверно повысило уровень фосфора в крови опытных телят. Коэффициент де Ритиса у животных до опыта превышал уровни нормы, применение галенового препарата нормализует этот показатель. Установлено также, что препарат приводит к нормализации кальций фосфорного соотношения

Asymptotic analysis of operator families and applications to resonant media

We give an overview of operator-theoretic tools that have recently proved useful in the analysis of boundary-value and transmission problems for second-order partial differential equations, with a view to addressing, in particular, the asymptotic behaviour of resolvents of physically motivated parameter-dependent operator families. We demonstrate the links of this rich area, on the one hand, to functional frameworks developed by S. N. Naboko and his students, and on the other hand, to concrete applications of current interest in the physics and engineering communities.Comment: 60 pages, 2 figures; a survey of recent results in the area, see also arXiv:2010.13318, arXiv:1808.03961, arXiv:1703.06220, arXiv:1510.0336

ASSESSING EFFICIENCY OF THE CONIFEROUS ENERGY SUPPLEMENT IN THE DIET OF DAIRY COWS FOR MAINTAINING PRODUCTIVE HEALTH

  Objective: This study was aimed at assessing efficiency of the original coniferous energy supplement in the diet of cows at the end of the dry period - beginning of lactation - for improving the energy density of diets, enriching them with vitamins and major and minor nutrient elements, improving milk productivity, and maintaining productive health.Methods: The scientific-production experiment was performed on the basis of the Lukoshkino†unit of the Klenovo-Chegodaevo†research farm (Moscow) on twenty cows. The preparation was fed at the rate of 150 g for 20 days before calving and for 30 days after calving.Results: Studies have found the positive effect of the preparation on the average daily milk yield, natural fat content increased by 5.4%-6.9% (with butterfat percentage increased by 0.09%), and reduced cost of feed per unit of obtained product.Conclusion: The use of the preparation promoted enzymatic processes in the rumen, had positive effect on the carbohydrate-lipid and protein metabolism, and had no negative effect on the non-specific resistance of cows

Confinement-Controlled Water Engenders Unusually High Electrochemical Capacitance

The electrodynamics of nanoconfined water have been shown to change dramatically compared to bulk water, opening room for safe electrochemical systems. We demonstrate a nanofluidic “water-only” battery that exploits anomalously high electrolytic properties of pure water at firm confinement. The device consists of a membrane electrode assembly of carbon-based nanomaterials, forming continuously interconnected water-filled nanochannels between the separator and electrodes. The efficiency of the cell in the 1–100 nm pore size range shows a maximum energy density at 3 nm, challenging the region of the current metal-ion batteries. Our results establish the electrodynamic fundamentals of nanoconfined water and pave the way for low-cost and inherently safe energy storage solutions that are much needed in the renewable energy sector