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The effect of C60-fullerene aqueous solution (with daily oral dose of 1 mg/kg) on the restoration of hysteresis effects of muscle contraction responsible for the correction of the precise positioning of joints in the development of atrophic changes associated with long-term immobilisation is investigated. A clinical model of Achilles-tendon rupture is used to study the development of muscle atrophy. Muscle-contraction parameters are recorded on the 15th, 30th, and 45th day after the initiation of atrophy. The obtained results confirm the effectiveness of C60-fullerenes’ influence on the functions of the antioxidant system in the development of pathological processes. [ABSTRACT FROM AUTHOR]

The task of ensuring the end-to-end quality of service of heterogeneous wireless (WW) networks with random multiple access is considered. The processes of the occurrence of conflicts between the fairness and optimality of route selection and resource allocation in BP networks are analyzed. A technique for eliminating conflicts between fairness and optimality of resource distribution has been developed. It is shown that in the rational definition of radio access technology in heterogeneous networks, the functions of each level and, accordingly, the information parameters of the traffic at this level can be attributed to one of two alternative groups: functions that depend on a specific technical implementation of the network or functions oriented to work with applications. Accordingly, a global approach to the optimal selection of a radio access technology (RAT) is formulated as a problem with super-polynomial complexity, and an approach for RAT selection using a distributed metaheuristic tabu search algorithm based on the peak rate that users are able to perceive is proposed. A distributed RAT selection system based on metaheuristic optimization of the set of routes with elimination of redundancy has been developed. A combined metaheuristic optimization method based on a dual approach - a combination of adaptability and learning from previously obtained results - has been developed. An original method of one-time overcoming the prohibition of tabu search paths has been introduced: when the next step is considered unpromising and should be rejected, but good results were obtained from the previous steps - this step is allowed, and the obtained result is counted as an initial one for further search. A general expression for the distribution of the access point’s stay time in a heterogeneous wireless network together with the access point boundary crossing probabilities is obtained. Numerical results and simulation results show satisfactory agreement. [ABSTRACT FROM AUTHOR]

Nerve conduction under stimulation of the rat muscle soleus after longterm immobilisation of the hind limbs is studied using a clinical model— the rupture of the Achilles tendon. The analysis of mechanokinetic parameters of muscle contraction is performed on day 45 after the initiation of atrophy. The water-soluble C60 fullerene is used as a therapeutic nanoagent at a daily oral dose of 1 mg/kg during the experiment. The delay in the time of muscle contraction caused by 1 Hz and 2 Hz stimulations reveals a sharp increase from 98 ± 6 ms in control to 443 ± 8 ms and 487 ± 7 ms after atrophy initiation, respectively. This delay is associated with a decrease in the conductivity of the nerve stimulus due to destructive changes in the nervous tissue caused by muscle atrophy. In all the tests performed with the therapeutic administration of water-soluble C60 fullerenes, an increase in nerve conduction by 31 ± 2% and 36 ± 2% at 1 Hz and 2 Hz stimulation, respectively, is detected in relation to the atrophy group. This indicates the presence of compensatory activation of the endogenous antioxidant system by C60 fullerenes in the process of dystrophic changes caused by prolonged immobilisation. [ABSTRACT FROM AUTHOR]

Operators are often subjected to a high working memory load as far as any possibly useful information must always be available and presented to the operator. Thus, we assumed that they may have developed adaptations in mechanisms of working memory realization that help them to be more efficient in information overload conditions. Our aim was to define differences in visual working memory functioning in radar station operators (RSO) and other military profession representatives. For this purpose, in parallel with the performance of original computer tests for the visual working memory identification, which had two levels of complexity, we recorded an electroencephalogram with subsequent coherent and LORETA analysis and electrocardiogram with subsequent determining of stress index of the regulatory systems. It was found that reaction time, as well as the number of errors in both tests, didn't differ significantly for the two groups. At the same time, the control group had a significantly higher number of θ-band coherent connections in the frontal lobe in both tests, which could indicate a higher level of mental stress and emotional involvement. This assumption was confirmed by the stress index dynamic in the control group. LORETA analysis showed that in the RSO group, the degree of fronto-parietal, cingulo-opercular networks, cuneus and precuneus involvement was at a high level from the very first tasks, while in the control group, it increased with task complexity, that is the evidence of adaptive changes in the working memory of RSO, due to which they successfully cope with information overload. [ABSTRACT FROM AUTHOR]

A comparison of biomechanical and biochemical markers of muscle soleus and muscle gastrocnemius fatigue in rats for two days after 5 days of using antioxidant C60 fullerene (daily dose was 1 mg⋅kg-1) was performed. It was shown that its long-term use to increase muscle strength response against the back-ground of muscle fatigue by 60-65 and 35-40% in slow and fast muscle, respectively. The residual effect of water-soluble C60 fullerene on slow muscle remains significant (20-25%) even after 2 days after discontinuation of the drug. At the same time, its residual effect on fast muscle on the 2nd day remains at a minimum level, which does not significantly increase muscle performance. Prolonged usage of water-soluble C60 fullerene helps to reduce oxidative processes by 30-40% in fast and by 21-25% in slow muscles by maintaining a balance between prooxidants and antioxidant defense system. A comparative analysis of oxidative stress markers and indicators of the state of antioxidant defense systems in fast and slow muscles showed that the residual therapeutic effect of water-soluble C60 fullerene after long-term use is 30-40% higher in muscle soleus than in muscle gastrocnemius. The obtained results demonstrate the long-term kinetics of water-soluble C60 fullerene excretion from the body, which contributes to long-term (at least two days) compensatory activation of the endogenous antioxidant system in response to muscle stimulation, which should be considered when developing new therapeutic drugs based on it. [ABSTRACT FROM AUTHOR]

The effects of 60 fullerene and the known exogenous antioxidant Nacetylcysteine (NAC) on the biomechanics of contraction of fast (m. soleus) and slow (m. gastrocnemius) muscles of rats with fatigue are compared. 60 fullerene and NAC are administered intraperitoneally in single doses of 1 and 150 mg/kg, respectively, 2 hours before the onset of muscle fatigue. As shown, the therapeutic effect of 60 fullerene on the correction of the retention time of the maximum level of muscle response after fatigue initiation is 20% and 25%, respectively, for slow and fast muscles, that is 2.5 and 1.7 times higher a similar effect of NAC. Therapeutic usage of NAC and 60 fullerene reduces the amount of lactate and creatinine in the blood of animals by 16% and 28% and 12% and 31%, respectively. The results suggest a real prospect for the using 60 fullerenes as potential nanoagents to improve skeletal muscle function by modifying mechanisms, which play an important role in the development of muscle fatigue. [ABSTRACT FROM AUTHOR]

Intramuscular injections of water-soluble C60 fullerenes (of 0.5 mg/kg dose) are shown to prolong the time of onset of skeletal muscle fatigue of rats due to their effect on the prooxidant–antioxidant muscle homeostasis. For the first time, it was found that, after the introduction of C60 fullerenes, the decrease of muscle-contraction force by 50% from the initial values is almost twice as slow as in control with stimulation of 1 Hz (slow muscle fatigue) and by 45–55% slower than stimulation with a frequency of 2 Hz (rapid muscle fatigue). The obtained data indicate the difficulty of determining the optimal model of therapeutic effect of C60 fullerenes on the processes of skeletalmuscle fatigue that requires further research in vivo. [ABSTRACT FROM AUTHOR]