[Hypersomnia in mental disorders]

Hypersomnia is a group of diseases that share the main symptom - excessive daytime sleepiness, not caused by disturbances in nocturnal sleep or circadian rhythms. Excessive daytime sleepiness is present in 15.6% of adults in the world, a Russian study showed a prevalence of 39.2%. It is associated with a wide range of comorbidities, including obesity and mental disorders, on the other hand, the presence of hypersomnia increases the likelihood of mental illness. People with hypersomnia are more likely to take medications, have a decreased quality of life, spend more health care resources, and more often receive social benefits. The heritability is estimated to be about 40% for sleep duration and 17% for excessive daytime sleepiness. Hypersomnia in mental disorders is secondary. It most often occurs in patients with depression or bipolar disorder. To assess the severity of daytime sleepiness, self-observation and objective methods, including the multiple sleep latency test, actigraphy, polysomnography, are used. In the differential diagnosis of hypersomnia in psychiatric disorders, it is necessary to make a differential diagnosis with hypersomnia caused by taking medications or other substances and insufficient sleep syndrome. The etiology of prolonged sleep in psychiatric disorders is complex, and includes biological and psychological causes. The relationship between self-reported hypersomnia and sleep actually obtained is still unclear. Results of daily polysomnography show a significant increase in time in bed during the day and night (clinophilia). Therapy of hypersomniac syndromes should be done taking into account the etiology of the disease. In cases of secondary nature, the main efforts should be directed to the treatment of the underlying mental disorder causing somnolence.

Kinetic Model and Experiment for Self-Ignition of Triethylaluminum and Triethylborane Droplets in Air

Triethylaluminum Al(C₂H₅)₃, TEA, and triethylborane, B(C₂H₅)₃, TEB, are transparent, colorless, pyrophoric liquids with boiling points of approximately 190 °C and 95 °C, respectively. Upon contact with ambient air, TEA, TEB, as well as their mixtures and solutions, in hydrocarbon solvents, ignite. They can also violently react with water. TEA and TEB can be used as hypergolic rocket propellants and incendiary compositions. In this manuscript, a novel scheme of the heterogeneous interaction of gaseous oxygen with liquid TEA/TEB microdroplets accompanied by the release of light hydrocarbon radicals into the gas phase is used for calculating the self-ignition of a spatially homogeneous mixture of fuel microdroplets in ambient air at normal pressure and temperature (NPT) conditions. In the primary initiation step, TEA and TEB react with oxygen, producing an ethyl radical, which can initiate an autoxidation chain. The ignition delay is shown to decrease with the decrease in the droplet size. Preliminary experiments on the self-ignition of pulsed and continuous TEA-TEB sprays in ambient air at NPT conditions are used for estimating the Arrhenius parameters of the rate-limiting reaction. Experiments confirm that the self-ignition delay of TEA-TEB sprays decreases with the injection pressure and provide the data for estimating the activation energy of the rate-limiting reaction, which appears to be close to 2 kcal/mol.

[COVID-19 and stress-related disorders]

Since the WHO declared the COVID-19 outbreak a pandemic, the most actual problem has been a change in the lifestyle of the population of Russia and the rest of the world. Fear of illness, self-isolation/quarantine, and decreased quality of life have dramatically increased the level of stress-related disorders in the population. The main mental disorders arising from stress refer to anxiety disorders (post-traumatic stress disorder (PTSD), panic disorder, agoraphobia, social phobia, generalized anxiety disorder), obsessive-compulsive disorder, depressions of varying severity and conversion reactions. The symptoms and early warning signs of stress-related disorders may be chronic or episodic. Stress-related disorders are corrected with psychotropic therapy, which aims to restore the balance of neurotransmitters. Current first choice agents for the treatment of both pathological anxiety and depression are selective serotonin reuptake inhibitors (SSRIs). During the pandemic, the SSRI fluvoxamine is of special interest. Its mechanisms of action are recognized as potentially useful for treating COVID-19 infection. Two studies confirming the efficacy and safety of fluvoxamine in the treatment of coronavirus infection are described.

Diffraction on periodic surface microrelief grating with positive or negative optical anisotropy

Diffraction optical elements (DOE) are important elements of systems for images displaying and processing. The DOE materials with both positive and negative birefringence enhance performances and functionality of such systems. We have calculated the diffraction of rays passing through optically anisotropic grating with surface microrelief by using our original Exedeep software. At the first time the diffraction parameters for both transmitted and reflected TE- and TM-waves are calculated for materials with both positive and negative optical anisotropy. The simulation results are to be used to create DOE for the visible, UV, IR and THz ranges.

Alkynyl triphosphine copper complexes: synthesis and photophysical studies

A chelating triphosphine was used to synthesize luminescent mono-, di- and trinuclear copper(i) alkynyl complexes, the photophysical properties of which are determined by the nature of alkynyl groups.

Local prevention of thrombosis in animal arteries by means of magnetic targeting of aspirin-loaded red cells

Thrombosis was induced in 18 dog and 16 rabbit arteries by surgically inverting a vascular wall flap into its lumen. A completely occluding red thrombus was formed inside the vessel 4 to 5 hours later in 80% of cases. SmCo5 magnet was secured externally to one of the arteries. The constant magnetic field produced by the magnet had no influence on the clot formation. Autologous red cells loaded with ferromagnetic colloid compound and aspirin were administered intravenously and completely aborted arteriothrombosis on magnet-supplied side with no deterioratory effect on clot formation in the control artery.

Magnetically driven thrombolytic preparation containing immobilized streptokinase-targeted transport and action

Streptokinase was immobilized on the magnetic carrier at a concentration of 2,000-2,700 IU/ml of preparation. Thrombosis was induced in both canine carotid arteries by means of the vascular wall flap inverting into its lumen. The red, completely occluding thrombus was formed inside the vessel 4-5 h later. A samarium-cobalt magnet was secured externally to one of the arteries. After the clot formation the magnetically immobilized streptokinase was injected intravenously. The preparation concentrated in the region of the magnetic field action caused complete thrombus degradation and normal blood flow restoration; no effect on the clot in the control artery was observed.

Comparison of different lasers in terms of thrombogenicity of the laser-treated vascular wall

The thrombogenic properties of the laser-treated vascular wall are reported as quantitatively assessed on the basis of 33 experiments with peripheral canine vessel segments. Three types of surfaces, namely, 1) intact, 2) mechanically de-endothelized, and 3) postlaser, have been simultaneously exposed to platelet-enriched plasma in a sequentially organized artificial circulation system. Then the adherent platelets have been counted on the treated surfaces, and the relative thrombogenicity index has been calculated according to the equation T = (A1 - Aint)/(Ad - Aint), where Aint, Ad, A1 = the adherent platelet counts on intact, mechanically de-endothelized, and laser-treated surfaces, respectively. The following lasers have been evaluated: 1) Nd-YAG, 1,060 nm, continuous wave, 4W; 2) argon-ion, 480 and 514 nm and argon-ion, 350 nm, continuous-wave, 1 W and 400 mW [corrected], respectively; 3) excimer XeCl, 308 nm, pulsed, 30 mJ per pulse, repetition rate 10 Hz [corrected]; and also 4) the laser-heated metal probe (2 mm diameter, Trimedyne, Nd-YAG) 1,060 nm, 8 W. The thrombogenicity index values obtained were 83 +/- 7, 72 +/- 8, 57 +/- 9, 63 +/- 7, and 82 +/- 9%, respectively. The differences between these values were statistically insignificant. The data are suggestive of the essential requirement of, at least, anticoagulant therapy after laser angioplasty irrespective of the laser type.