Variational problem of adaptive optimal control. Theoretical and applied computer analysis

The problem of adaptive optimal control of a dynamical system, which belongs to the class of conditional variational problems with moving boundaries, is considered. A variational and computer study of the controlled adaptive motion of a material point is carried out for the problem of the energy quality functional minimizing with a moving, not predetermined right transboundary and in the case when the mass of the point changes depending on the unfixed final time. The problem is solved using the schemes and procedures of the classical calculus of variations, as well as adaptive estimation techniques, including the derivation of the variation of the auxiliary quality functional, the corresponding Euler equations, and the adaptive estimation algorithm. When solving a general conditional variational problem, the obtained closed system of differential equations was studied for the formation of an adaptive optimal control system for a dynamic plant with a given performance functional. The results of the unconditional formulation of the problem are generalized to the case of additional differential (nonholonomic) and holonomic constraints. In a variational adaptive optimal control problem, the transversality condition is formulated in terms of the local programming condition. The developed variational scheme of adaptive optimal synthesis can be used in the calculation and design of controlled dynamic systems. This optimization scheme is also promising for use in systems where operating time is non-fixed in advance. The results achieved in this paper concern obtaining specific equations, expressions, and formulas relative to the model example under study and finding graphs of the main time functions that determine the nature of the movement of the control object and the quality of the corresponding transients. The proposed adaptive optimal control algorithms for purposeful movement of the studied material point were tested in digital mode and showed their effectiveness which makes them promising for further use in more complex nonlinear adaptive systems of dynamic optimal control

PROTECTIVE ACTIVITY OF ASCORBIC ACID AT INFLUENZA INFECTION

Abstract. Ascorbic acid (vitamin C, AA) is an essential nutrient of the human diet due to its participation on numerous regulatory and enzymatic processes. AA takes part in such vital physiological processes as hormone production, collagen synthesis, stimulation of the immune system, etc. In the present review the activities of AA are considered that provide its protective effect at influenza infection. This effect can be result of direct virus-inhibiting activity of AA as well as of anti-inflammatory and antioxidant properties. Oxidative stress during influenza infection leads to nonspecific damage of the pulmonary tissue and subsequent inflammation of the lungs. The antioxidant activity of AA results in alleviation of infection due to suppression of tissue damage as well as in inhibition of reactive oxygen species-mediated signal transduction and regulatory reactions. After oxidation by ROS, AA is converted to dehydroascorbic acid (DAA) and inhibits the key enzymes of NF-κB pathway, such as kinases IKKα and IKKβ. AA itself blocks the activity of another component of the NF-kB pathway, kinase IKKβ(SS/EE), whose activity is directed to the phosphorylation of the factor IκBα. As a result, activation of NF-κB and its transport to the nucleus does not occur. Thus, AA performs a dual function: first, it neutralizes free radicals, preventing them from activating NF-κB, and secondly, the product of its oxidation, DAA, further blocks the activation of this pathway. In addition, in some cases AA results in the decrease in the infectious activity of influenza virus that is not due to the antioxidant activity of AA, but to direct virus-inhibiting activity. Taken together, the presented data suggests that the use of drugs with antiviral and antioxidant activity, as a combination of individual drugs or, as in the case of AA, as a single drug with complex activity, for treatment of influenza has advantages over the etiotropic drug monotherapy scheme

Activity of Ingavirin (6-[2-(1H-Imidazol-4-yl)ethylamino]-5-oxo-hexanoic Acid) Against Human Respiratory Viruses in in Vivo Experiments

Respiratory viral infections constitute the most frequent reason for medical consultations in the World. They can be associated with a wide range of clinical manifestations ranging from self-limited upper respiratory tract infections to more devastating conditions such as pneumonia. In particular, in serious cases influenza A leads to pneumonia, which is particularly fatal in patients with cardiopulmonary diseases, obesity, young children and the elderly. In the present study, we show a protective effect of the low-molecular weight compound Ingavirin (6-[2-(1H-imidazol-4-yl)ethylamino]-5-oxohexanoic acid) against influenza A (H1N1) virus, human parainfluenza virus and human adenovirus infections in animals. Mortality, weight loss, infectious titer of the virus in tissues and tissue morphology were monitored in the experimental groups of animals. The protective action of Ingavirin was observed as a reduction of infectious titer of the virus in the lung tissue, prolongation of the life of the infected animals, normalization of weight dynamics throughout the course of the disease, lowering of mortality of treated animals compared to a placebo control and normalization of tissue structure. In case of influenza virus infection, the protective activity of Ingavirin was similar to that of the reference compound Tamiflu. Based on the results obtained, Ingavirin should be considered as an important part of anti-viral prophylaxis and therapy

IMPACT OF COINFECTION OF PV B19 ON THE COURSE AND PROGNOSIS OF MALARIA CAUSED BY PLASMODIUM FALCIPARUM

Parvovirus infection (PVI) is widespread in the world; more than 80% of the adult population have antibodies of IgG class to parvovirus B19. Malaria is a vector-borne parasitic disease caused by the protozoa of the genus Plasmodium, that is widespread in the countries of Africa, Southeast Asia, Oceania. The objective of the present study was to evaluate the effect of parvovirus B19 infection on the clinical course of malaria and the outcome of the underlying disease. During the period 2016–2018 blood plasma samples of 316 patients from the hospital of the Friya Prefecture of the Republic of Guinea (GR) with confirmed diagnosis of malaria were examined for the presence of PVB19 DNA. The clinical course of malaria in 316 examined patients was divided into group of either mild or complicated. In total, PVB19 DNA was detected in blood plasma in 55 of 316 patients (17.41±2.13%). But in the group with co-infection of PVB19 and P. falciparum complications were observed in 40 of 55 (72.73±2.75%) patients, and in 6 of 55 cases (10.91±4.40%) the disease resulted in death. In the group of patients with malaria without PVI, complications occurred in 99 of 261 patients (37.9±3.0%); of those 2 (0.77±0.54%) died. It was found that the most numerous group in the structure of malaria patients is represented by children under 5 (median 3) years (89, or 28.25±2.53%). Our results correlate with the data of other researchers who studied the PVI-associated malaria in children in malaria-endemic regions: among children under 5 years, the absolute majority of cases of PVI was accompanied by a complicated course of malaria. The primary parvovirus infection can aggravate the course of malaria, especially when combined with other unfavorable conditions (iron deficiency, malnutrition, helminthic infections, co-infections, etc.). Thus, infection with PVB19 becomes a critical factor, which can provoke a severe life-threatening anemia, and also cause other complications