Abstract: A process is provided for the catalytic asymmetric reduction of ketones to provide alcohol reaction products which are enriched in one enantiomer. The asymmetric reduction is accomplished utilizing an achiral metal precatalyst in combination with an optically active additive.

Abstract: A process is provided whereby organic carbonyl substrates, including esters, lactones, ketones, amides and imides are reduced in a reaction with a silane reducing reagent and a catalyst. Exemplary catalysts include metal alkoxides and metal aryloxides.

Abstract: The present invention is a time vernier providing fine timing control of an input signal having coarse timing edges. The time vernier comprises a receiving means for receiving a value representing a desired time delay to be added to the coarse timing edge input. The desired time delay may have both fine and coarse delay aspects. The time vernier also comprises a first decoding means for decoding the fine delay aspect and generating fine delay control signals, as well as a second decoding means for decoding a coarse delay aspect and generating coarse delay control signals. A delay line is also included in the time vernier which has inputs to receive the input signal having coarse timing edges, the fine and coarse delay control signals, and a control voltage which automatically adjusts with temperature and power supply variations, so as to provide for temperature and power supply compensation. The delay line combines the fine and coarse delay signals to provide an output signal with fine timing edges.

Abstract: A method and apparatus are provided for use by dentists in determining the actual length of a root canal based upon a single x-ray picture. The method involves inserting a probe a known distance partially into the root canal before taking the x-ray picture. The picture is then analyzed to compare the visually observed, apparent lengths of the root canal and probe with the known length of the probe. The actual length of the root canal is determined by direct arithmetic proportion based upon the observed apparent lengths. The apparatus facilitates measurement of said observed apparent lengths utilizing manipulating knobs and an illuminated scale resembling a thermometer scale.