Approaches to the synthesis of heterocyclic -nucleosides.

This review is focused on the synthetic strategies to heterocyclic -nucleosides and covers the literature from 2011 to 2021. The main attention is paid to the following three approaches: the direct C-C coupling of a carbohydrate moiety with a preformed aglycon unit, the construction of a (pseudo)sugar residue on a pre-formed aglycon, and the construction of an aglycon on a pre-formed (pseudo)sugar. In each Section, the literature data are categorized in terms of the size of aglycon from simple to complex, the advantages and drawbacks of the reviewed approaches are discussed.

Pyrimido[1,2-]benzimidazoles: synthesis and perspective of their pharmacological use.

The review presents data on the synthesis as well as studies of biological activity of new derivatives of pyrimido[1,2-]benzimidazoles published over the last decade. The bibliography of the review includes 136 sources.

Cleaning of first mirrors in ITER by means of radio frequency discharges.

First mirrors of optical diagnostics in ITER are subject to charge exchange fluxes of Be, W, and potentially other elements. This may degrade the optical performance significantly via erosion or deposition. In order to restore reflectivity, cleaning by applying radio frequency (RF) power to the mirror itself and thus creating a discharge in front of the mirror will be used.

The role of the substantia nigra in cognitive activity in cats.

The role of the substantia nigra in cognitive processes of different levels of complexity was studied using an original method. Neurosurgical or neurochemical exclusion of the substantia nigra in cats led to significant impairment of conditioned reflex activity, generalization and abstraction processes; these recovered with pharmacological treatment directed to the dopaminergic system, with partial recovery after treatment directed to the GABAergic and cholinergic systems. Treatment directed to the serotoninergic system was ineffective.

[Behavioral therapy of ticks with negative reinforcement in children].

Thirty-two children suffering from motor and vocal ticks exhibited weakness and distonia of ticks-prone muscles were examined. Based on the results obtained earlier, a complex of physical exercises has been worked out and conducted for 20 days. The patients were divided into 3 groups: 1st (n = 10) group did the exercises daily for training the ticks-prone muscles; the 2nd one (n = 10) exercised only after tick's appearance--negative reinforcement; 3rd group (n = 12) did exercises after tick's appearance as well but on irregular basis--probable negative reinforcement.