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Within distances to Uranus of about 6 x 10(6) kilometers (inbound) and 35 x 10(6) kilometers (outbound), the planetary radio astronomy experiment aboard Voyager 2 detected a wide variety of radio emissions. The emission was modulated in a period of 17.24 +/- 0.01 hours, which is identified as the rotation period of Uranus' magnetic field. Of the two poles where the axis of the off-center magnetic dipole (measured by the magnetometer experiment aboard Voyager 2) meets the planetary surface, the one closer to dipole center is now located on the nightside of the planet. The radio emission generally had maximum power and bandwidth when this pole was tipped toward the spacecraft. When the spacecraft entered the nightside hemisphere, which contains the stronger surface magnetic pole, the bandwidth increased dramatically and thereafter remained large. Dynamically evolving radio events of various kinds embedded in these emissions suggest a Uranian magnetosphere rich in magnetohydrodynamic phenomena.

Planetary radio astronomy measurements obtained by Voyager 2 near Saturn have added further evidence that Saturnian kilometric radiation is emitted by a strong dayside source at auroral latitudes in the northern hemisphere and by a weaker source at complementary latitudes in the southern hemisphere. These emissions are variable because of Saturn's rotation and, on longer time scales, probably because of influences of the solar wind and Dione. The electrostatic discharge bursts first discovered by Voyager 1 and attributed to emissions from the B ring were again observed with the same broadband spectral properties and an episodic recurrence period of about 10 hours, but their occurrence frequency was only about 30 percent of that detected by Voyager 1. While crossing the ring plane at a distance of 2.88 Saturn radii, the spacecraft detected an intense noise event extending to above 1 megahertz and lasting about 150 seconds. The event is interpreted to be a consequence of the impact, vaporization, and ionization of charged, micrometer-size G ring particles distributed over a vertical thickness of about 1500 kilometers.

Detection of very intense short radio bursts from Neptune was possible as early as 30 days before closest approach and at least 22 days after closest approach. The bursts lay at frequencies in the range 100 to 1300 kilohertz, were narrowband and strongly polarized, and presumably originated in southern polar regions ofthe planet. Episodes of smooth emissions in the frequency range from 20 to 865 kilohertz were detected during an interval of at least 10 days around closest approach. The bursts and the smooth emissions can be described in terms of rotation in a period of 16.11 +/- 0.05 hours. The bursts came at regular intervals throughout the encounter, including episodes both before and after closest approach. The smooth emissions showed a half-cycle phase shift between the five episodes before and after closest approach. This experiment detected the foreshock of Neptune's magnetosphere and the impacts of dust at the times of ring-plane crossings and also near the time of closest approach. Finally, there is no evidence for Neptunian electrostatic discharges.

The Voyager 1 planetary radio astronomy experiment detected two distinct kinds of radio emissions from Saturn. The first, Saturn kilometric radiation, is strongly polarized, bursty, tightly correlated with Saturn's rotation, and exhibits complex dynamic spectral features somewhat reminiscent of those in Jupiter's radio emission. It appears in radio frequencies below about 1.2 megahertz. The second kind of radio emission, Saturn electrostatic discharge, is unpolarized, extremely impulsive, loosely correlated with Saturn's rotation, and very broadband, appearing throughout the observing range of the experiment (20.4 kilohertz to 40.2 megahertz). Its sources appear to lie in the planetary rings.

A three-dimensional x-ray diffraction study of aspartate transcarbamylase to 5.5-angstrom resolution, with the aid of four isomorphous heavy atom derivatives, indicates the presence of a central aqueous cavity approximating an oblate spheroid about 25 by 50 by 50 angstroms in dimension, within a molecule about 90 by 110 by 110 angstroms in largest dimensions.

A chemoreceptor neuron of the adult blowfly contains several different sites for activation by sugars. It appears that the number or affinity of the sites for fructose and perhaps those for glucose may be depressed by rearing the larvae in the presence of the sugar in question.

The concentration of trehalose in the blood of Phormia regina was found to determine the rate of energy expenditure during flight as reflected in measurements of the wing-beat frequency. Fat body was found to be the source of blood trehalose; either endogenous or exogenous substrates are used for its synthesis.