Purification of methylmalonyl-CoA mutase from Propionibacterium shermanii using affinity chromatography.

A novel procedure for the purification of methylmalonyl-CA mutase from Propionibacterium shermanii has been described which employs affinity chromatography on a column of immobilized vitamin B-12 linked covalently to Sepharose. The method has the advantage of being simple and rapid, thus enabling the purification of the enzyme to near homogeneity with good yields.

Electrooptical array processor for complex signals.

An interdigital finger pattern is derived, which can modulate both the amplitude and phase of light in a total internal reflection configuration. An application to radio antenna array processing is illustrated.

Pulsar sub-pulses and the emission process.

This article describes another regular phenomenon in the sub-pulse behaviour of pulsars. The drift speed of successive sub-pulses follows a sawtooth pattern with a linearly increasing drift speed and sudden jumps as the speed drops to repeat the cycle.

Spatial frequency analysis with a new incoherent optical approach.

A new approach to spatial frequency analysis is presented that offers the potential of analyzing 2-D distributions at video frame rates. It uses a light panel (or light shutter) whose light intensity distribution (or light transmission distribution) sequentially scans through all possible spatial frequencies in both magnitude and orientation. The spatial frequency spectrum of the transparency (or scene) onto which the panel is imaged can be directly displayed as a TV-type picture at video rates.

Incoherent optical 1-bit cross-correlators for radio antenna arrays.

A new incoherent optical approach to an important digital signal processing problem in radio astronomy is presented. It greatly simplifies the many thousands of 1-bit digital cross-correlations that can be required by using a digitally controlled light panel and photodiode array.

Spectral analysis of a temporal signal with incoherent optics.

A fast parallel approach to the spectral analysis of a time-varying signal is presented. The technique, which uses a light emitting diode array and an integrating photodiode array, can offer the potential of a thousand or more spectral points and data rates beyond 10 MHz.

Inhibition of liver fructose 1,6-bisphosphatase activity by Zn2+: reversal by imidazole pyruvate.

Imidazole pyruvate was found to be a very potent natural chelating agent in reversing the inhibition of liver fructose 1,6-bisphosphatase activity by Zn2+. This metabolite may play a physiological role in gluconeogenesis.