Copying of RNA Sequences without Pre-Activation

Enzyme-free genetic copying of DNA and RNA sequences

The copying of short DNA or RNA sequences in the absence of enzymes is a fascinating reaction that has been studied in the context of prebiotic chemistry. It involves the incorporation of nucleotides at the terminus of a primer and is directed by base pairing. The reaction occurs in aqueous medium and leads to phosphodiester formation after attack of a nucleophilic group of the primer. Two aspe...

Sidewards without copying

A traditional movement step relates a single source position to a single c-commanding target position, and never moves an argument to another argument position. But head movement involves non-c-command relations, and control relates two argument positions that are not always in a c-command relation. Special mechanisms could be invoked for these things, but a different strategy slightly generali...

Children's tactual exploration and copying without vision.

Relation Between RNA Sequences, Structures, and Shapes via Variation Networks

Background: RNA plays key role in many aspects of biological processes and its tertiary structure is critical for its biological function. RNA secondary structure represents various significant portions of RNA tertiary structure. Since the biological function of RNA is concluded indirectly from its primary structure, it would be important to analyze the relations between the RNA sequences and t...

Cerebellar activation during copying geometrical shapes.

We studied functional MRI activation in the cerebellum during copying 9 geometrical shapes (equilateral triangle, isosceles triangle, square, diamond, vertical trapezoid, pentagon, hexagon, circle, and vertical lemniscate). Twenty subjects were imaged during 3 consecutive 45-s periods (rest, visual presentation, and copying). First, there was a positive relation between cerebellar activation an...