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We analyzed the topography and quantitative characteristics of changes in a blood oxygenation level-dependent (BOLD) signal accompanying movements of the fingers and hand performed by healthy humans. Three test movements characterized by different levels of complexity were united in an integrated paradigm of activation. We assumed that such a paradigm should promote the understanding of mechanisms of functioning of separate neuronal networks controlling motor functions and their grouping in scaling networks responsible for general control of motor activity by the CNS. Concurrently with the processes of activation of the sensorimotor network, we observed partial deactivation of certain nodi of the default-mode network (DMN) and formation of functional connectivities independent of the performance of the tasks. This confirms the statement on the heterogeneity of the DMN, whose different parts can be simultaneously desynchronized and can function in an offline mode. Analysis of the frequency spectrum of fluctuations of the BOLD signal allowed us to conclude that the sensorimotor network and DMN function simultaneously; however, each of them demonstrates direct (for the sensorimotor network) and inverse (for the DMN) correlation between changes in the BOLD signal and the successfulness of performance of the motor task. [ABSTRACT FROM AUTHOR]

The possibility of electrocatalysis by sulfur dioxide has been demonstrated in the trifluoromethylation of thiophenols by Freon F13B1 (CFBr) to form trifluoromethyl aryl sulfides. A study has been made of the influence of the mediator concentration, the electronic structure of the thiophenol, and the electrolysis conditions on the course of the trifluoromethylation process. [ABSTRACT FROM AUTHOR]

Variations in the content of acid soluble nucleotides at different growth stages of the producer of pectolytic enzymes-the fungus Sclerotinia sclerotiorum were measured. The initial growth stage was characterized by an increased content of adenyl nucleotides whose amount decreased by the 48th hour. In the 48-hour mycelium guanyl nucleoside mono- and diphosphates were the major components of the nucleotide pool. Throughout the entire cultivation cytidyl derivatives occurred in trace quantities.