POSSIBILITIES FOR CORRECTING COGNITIVE DEFICITS IN STROKE IN PEOPLE WHO HAVE HAD COVID-19

Relevance. Mnestic functions in patients after stroke and coronavirus infection are not restored completely. Nowadays, the search for ways to overcome in such patients is actual. Objective: to find out the possibility of cognitive deficiency’ overcoming in persons after stroke who have suffered from COVID-19 by Phenibut pharmacocorrection and magnetic therapy. Materials and methods. 46 patients aged 40-60 years who had COVID-19 in anamnesis and ischemic stroke in the post-covid period were divided into 3 groups at the stage of comprehensive rehabilitation. In the 1st group (n=15) - the control group - no nootropic drugs and physiotherapeutic procedures were not asdministered; in group 2 (n=15), magnet stimulation procedures were performed for 20 days (frequency of basic impulses 180-195 Hz, frequency of a group of impulses 12,5-29 Hz, average induction of magnetic fields within 100 μT); group 3 (n=16) took Phenibut (β-Phenyl-GABA) one tablet (250 mg) 3 times a day for three months. The study of cognitive functions was carried out with the help of a short mental state scale - MMSE, a set of tests for the study of frontal dysfunction - FAB, a test for memorizing of 10 words according to the A.R. Luria’s method and clock drawing testing All groups were tested twice: at the beginning of the study and after three months. The obtained data were processed statistically; an ordinal logistic regression model was applied, in particular logistic regression with a cumulative relationship. The results. In group 2 the result of the subtest "Voluntary attention" improved (3,8±0,3 points vs. 3,1±0,2 in the control) and the FAB test (15, 2±1,2 points vs. 11,3±0,4 in control). In group 3, the cognitive functions in the MMSE (26,1±0,8 points vs. 21,2±0,6 in the control) and FAB (16,3±0,6 points vs. 11,3±0,4) tests probably improved. The results of the subtests "Discretionary attention" (3,8±0,1 points vs. 3,1±0,1) and "Memory" (2,6±0,2 points vs. 2,0±0,1) improved. In the test for 10 words memorizing, the difference in indicators, compared to the control, was in each subsequent presentation: 1,0±0,05; 1,1±0,09; 1,7±0,10 words, in delayed presentation 1,75±0,05 (in all cases p<0.05). Conclusions. The use of Phenibut and magnetic therapy in patients who have suffered a stroke after COVID-19 leads to regression of cognitive deficiency and depressive symptoms. The effect of Phenibut turned out to be better - the odds ratio, compared to the control, was 13,1

Foliations of Isonergy Surfaces and Singularities of Curves

It is well known that changes in the Liouville foliations of the isoenergy surfaces of an integrable system imply that the bifurcation set has singularities at the corresponding energy level. We formulate certain genericity assumptions for two degrees of freedom integrable systems and we prove the opposite statement: the essential critical points of the bifurcation set appear only if the Liouville foliations of the isoenergy surfaces change at the corresponding energy levels. Along the proof, we give full classification of the structure of the isoenergy surfaces near the critical set under our genericity assumptions and we give their complete list using Fomenko graphs. This may be viewed as a step towards completing the Smale program for relating the energy surfaces foliation structure to singularities of the momentum mappings for non-degenerate integrable two degrees of freedom systems.Comment: 30 pages, 19 figure

Lifetime distributions in the methods of non-equilibrium statistical operator and superstatistics

A family of non-equilibrium statistical operators is introduced which differ by the system age distribution over which the quasi-equilibrium (relevant) distribution is averaged. To describe the nonequilibrium states of a system we introduce a new thermodynamic parameter - the lifetime of a system. Superstatistics, introduced in works of Beck and Cohen [Physica A \textbf{322}, (2003), 267] as fluctuating quantities of intensive thermodynamical parameters, are obtained from the statistical distribution of lifetime (random time to the system degeneracy) considered as a thermodynamical parameter. It is suggested to set the mixing distribution of the fluctuating parameter in the superstatistics theory in the form of the piecewise continuous functions. The distribution of lifetime in such systems has different form on the different stages of evolution of the system. The account of the past stages of the evolution of a system can have a substantial impact on the non-equilibrium behaviour of the system in a present time moment.Comment: 18 page

Application of nanostructural nickel titanium implants with shape memory effect to modern dental practice

The results of clinical treatment of severe periodontal diseases by application of the new functional implants based on nanostructural NiTi alloy with shape memory effect are presented. The nanostructure in NiTi alloy is attained by severe plastic deformation, particularly by equal channel angular pressing. Several new types of NiTi implants are developed, including dental implants (to replace the removed teeth) and trans radix implants (to enforce teeth and to attach teeth to the jaw bone). The surface of nanostructured NiTi implants is covered by the carbyne layer in order to ensure high bio-compatibility. The new treatment procedure is proposed which includes the injection into the jawbone tissue of the mixture based on powdered NiTi alloy. These injection implants will be incorporated into living bone tissue. The result will be the growth of the shell of the new healthy dense bone. The NiTi particles behave structurally similar to healthy bones, i.e. living tissue cells incorporate with them followed by small vessels and nerves. As a result the implants will not be rejected for a long time. The summary results of 3 years’ practice of the successful application of these new implantation system in dentistry are presented. The ease of implementation of the new NiTi dental shape memory implants and the ease at which they can be adopted to bone tissue, especially in cases where it’s in deficit are highlighte