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The arrival of Italian architects and masters of art and other skills in the Grand Duchy of Moscow in the second half of the 15th century, and the businesses of the “Frjazins” in Moscow and other cities, make up a bright page in the history of Italian-Russian relations. However, it is not common knowledge that the first Italians came to Moscow a century earlier. Between 1363 and 1389, the Grand Duke Dmitrij Ivanovič gave a charter for hunting to a certain Andrej Frjazin. According to the charter, Andrej Frjazin’s predecessor was his uncle, Matvej Frjazin, who arrived in Moscow during the great reign of Dmitrij Ivanovič’s grandfather, Ivan Danilovič Kalita, between 1328/1331 and 1340. The businesses of the uncle and nephew in the Arctic North region were encouraged by the grand dukes of Moscow and carried out with their financial participation. Apparently, Matvej and Andrej Frjazin had trading relations with the Venetian trading post Tana, and they were likely not the only Italian merchants in Moscow in the 14th century. Among the citizens who defended Moscow from the attack of the Tatar troops in the summer of 1382, Russian chronicles mention a certain cloth merchant, Adam, who was most likely an Italian, and who could have had some trading relations with the Genoese colony of Kafa in the Crimea.

Concrete and reinforced concrete remain the most popular building materials for use in building structures in modern construction and production [...]

Bismuth telluride nanoparticles (NPs) attract attention due to the growth of sensitivity of the Bi2Te3 NPs-containing registrars in the near- and mid-infrared ranges. We describe the synthesis and characterization of these structures and analyze the low-order nonlinear optical properties of the colloidal suspensions and thin films containing Bi2Te3 NPs using 1064 and 532 nm, 10 ns pulses. Colloidal Bi2Te3 NPs demonstrate saturable absorption and positive nonlinear refraction (saturation intensity 7 × 108 W cm−2, nonlinear absorption coefficient β SA = −7 × 10−8 cm W−1, nonlinear refractive index γ = 9 × 10−12 cm2 W−1), while at stronger excitation by 532 nm, 10 ns pulses the reverse saturable absorption dominates over other nonlinear optical processes. We achieved significant growth of the nonlinear optical parameters of the thin films containing these NPs (film thickness l = 60 nm, β SA = −1.2 × 10−4 cm W−1, γ = 5 × 10−7 cm2 W−1 in the case of 532 nm probe radiation and β = −5 × 10−5 cm W−1, γ = 6 × 10−8 cm2 W−1 in the case of 1064 nm probe radiation) compared with colloidal Bi2Te3 NPs and discuss the observed peculiarities of the nonlinear response of Bi2Te3 nanostructures.

The dissolution of uranium oxides of various chemical compositions at different nitric acid solution concentrations and flow rates with obtaining uranyl nitrate solutions with a deficiency of NO3– anions was studied. The dependences of the solubility of uranyl hydroxonitrates on the nitric acid deficiency relative to stoichiometry and temperature were determined. It was shown that the solubility of hydroxonitrates in these solutions is higher than the solubility of uranyl nitrates obtained with stoichiometric or excess nitric acid content. In addition, the solubility of hydroxonitrates increases with temperature. The kinetics of uranium oxide dissolution in various temperature regimes with the formation of solutions with nitric acid deficiency relative to stoichiometry were studied. The initial dissolution rate of U3O8 in uranyl nitrate solution was determined in the temperature range from 40 to 104°C. [ABSTRACT FROM AUTHOR]

Nonspecific aortoarteritis is a systemic disease, which has been referred to the group of vasculitis affecting elastic and muscular arteries oflarge and medium calibre with the inflammatory processlocalized in the media and adventitia. The article presents the history of development of ideas about clinical manifestations, morphological changes and the course of the disease from 1761 to the present day, the timeline of medical advances in this disease studies. The genuine interest in nonspecific aortoarteritis arose at the beginning of thelast century, when the Japanese ophthalmologist Mikito Takayasu reported unusual changes in the retinal vessels of a 21-year-old Japanese girl suffering from recurrent bouts of syncope. The first publications dealt with clinical manifestations in the patients, who had only brachiocephalic arterial involvement. In the early 60s, it was found that nonspecific aortoarteritis (Takayasu's disease) can affect not only the branches of the aortic arch, but also the thoracic aorta, renal and visceral arteries. It was the mosaic clinical manifestations in patients with various forms of Takayasu's disease that caused the presentation of the disease in theliterature until the mid-1970s under various terms such as “pulseless disease”, “arteritis of young women”, “brachiocephalic arteritis”, “atypical coarctation of aorta”, “Martorell's syndrome”, “syndrome of obliteration of the supra-aortic trunks”, “panaortitis” or “panarteritis”, “aortitis syndrome”, “mid-aortic syndrome”, “occlusive thromboarteriopathy”. The review details the epidemiology and prevalence of this disease. Views not only on the etiology and pathogenesis, but also on the methods of treating this disease have changed since M. Takayasu's publication in 1908. Much attention is paid to the historical aspect of the first surgical procedures. Starting in 1951, the surgical method has firmly taken the lead in the treatment of stenosis of the carotid arteries, thoracic aorta, renal and visceral arteries. Surgical concepts changed, but the literature data indicate the sustainability of the basic principle of treatment: combination of surgical interventions and various antiinflammatory therapy regimens.

Aliterature review is dedicated to the use of Parnaparin in various surgical specialties. Prevention and treatment of thromboembolic complications is the major indication for the use of Parnaparin. In the review, the authors dwell on comparative studies of the efficacy oflow molecular weight heparins and unfractionated heparin. They also discuss in detail pharmacokinetics and pharmacodynamics of Parnaparin, its structure and effect on hemostasis components. Due tolack of direct comparative studies of variouslow molecular weight heparins, the authors provide reviews based on the network meta-analysis, which allowed them to identify the advantages of a specificlow molecular weight heparin by indirect comparison.There are few direct comparative studies of variouslow molecular weight heparins in theliterature, which does not allow for an objective assessment of their advantages and disadvantages. The authors do not only provideliterature data on direct comparative studies, but also show data on indirect comparisons (network meta-analysis). They analysed the efficacy of Parnaparin and otherlow molecular weight heparins for the prevention of thromboembolic complications, treatment of deep vein thrombosis and post-thrombophlebitic syndrome. The issues of the efficacy of Parnaparin in chronic arterial insufficiency and use in acute coronary syndrome are highlighted separately. The final part of the review is concerned with a promising, butlittle-known area of prophylaxis of restenosis and prevention of atherosclerosis progression. Experimental studies have allowed us to state that Parnaparin is one of the most effectivelow molecular weight heparins as far as thromboembolic complications are concerned. Parnaparin significantly reduces frequency of DVT events and, at the same time, decreases major bleeding risk as compared with unfractionated heparin. No dose adjustment is required in obese patients. Dose adjustments are based not on body weight but on risk factors for thrombosis, and obesity is only one of them to be considered to choose a dose. Amonglow molecular weight heparins, Parnaparin is one of the most potent drugs that reduces the proliferative and migratory capacity of smooth muscle cells; however, further research is needed to assess the prospects of using Parnaparin for the prevention of restenosis.

Graphene derivatives such as reduced graphene oxide and graphene-based composites are regarded as highly promising materials for optoelectronics and photodetection applications. Recently, considerable interest has arisen in using facile and environmentally friendly methods of graphene production. Despite significant progress in experimental studies of graphene and graphene-based composites, some fundamental questions about their structures, and the interaction between components in these systems, remain open. In the present work, several atomistic models of oxidized graphene fragments have been proposed based on XPS compositional analysis and DFT calculations, representing reduced graphene oxide produced by laser irradiation. The composition of the oxygen-containing functional groups, their equilibrium configuration and influence on the electronic and optical properties of graphene sheets were determined. The nature of the low-lying excited states, as well as the photoactive regions, has also been studied for the proposed models. The calculated absorption spectra of the graphene sheets were compared with experimental UV-Vis spectrum of rGO produced by laser ablation.