This note is intended to serve primarily as a reference guide to users wishing to make use of the Tropical Rainfall Measuring Mission data. It covers each of the three primary rainfall instruments: the passive microwave radiometer, the precipitation radar, and the Visible and Infrared Radiometer System on board the spacecraft. Radiometric characteristics, scanning geometry, calibration procedures, and data products are described for each of these three sensors.

Perfusion of isolated rabbit hearts with high potassium, low potassium, and quinidine solutions caused a diffuse widening of the QRS complex with no change in shape. These QRS changes were correlated with the magnitude and upstroke velocity of the ventricular transmembrane potential. An increase of QRS duration by 132% produced by high K was accompanied by a decrease of the action potential, resting potential, and upstroke velocity. A similar increase in QRS duration produced by quinidine was accompanied by a slow upstroke velocity but no change in magnitude of the action potential or resting potential. An increase of QRS duration by 49% produced by low K was accompanied by an increased action and resting potential, and upstroke velocity. We attributed the QRS changes produced by high K and quinidine, at least partly, to a slow conduction in the ventricle, caused by a slow upstroke velocity of the action potential. The QRS changes produced by low K could be explained by hyperpolarization. Early arrhythmias caused by low K were due to atrioventricular conduction disturbances.

band push broom microwave radiometer (PBMR) aboard the NASA C-130 aircraft was used to map surface soil moisture at and around the Konza Prairie Natural Research Area during the four intensive field campaigns of FIFE in May-October 1987. There was a total of 11 mea.urements over an area of 7 x 14 km during this period. One of the measurements was made on May 28 when soils were known to be saturated. This mea .urement wa. used for the calibration of the vegetation effect on the microwave absorption. Based on this calibration, the data from other measurements on other days were inverted to generate the soil mois ture maps. A good agreement was found when the estimated soil mois ture values were compared to those independently measured on the ground at a number of widely separated locations. There was a slight bias between the estimated and measured values, the estimated soil moisture on the average being lower by ahout 1.11 %. This small bias, however, was accounted for by the difference in time of the radiometric measurements and the soil moisture ground sampling.

Remote measurements of soil moisture contents over bare fields and fields covered with orchard grass, corn, and soybean were made during October 1979 with 1.4 GHz and 5 GHz microwave radiometers mounted on a truck. Ground truth of soil moisture content, ambient air and soil temperatures was acquired concurrently with the radiometric measurements. The biomass of the vegetation was sampled about once a week. The measured brightness temperatures over bare fields were compared with those of radiative transfer model calculations using as inputs the acquired soil moisture and temperature data with appropriate values of dielectric constants for soil‐water mixtures. Good agreement was found between the calculated and the measured results over 10°‐70° incident angles. The presence of vegetation was found to reduce the sensitivity of soil moisture sensing. At 1.4 GHz the sensitivity reduction ranged from ∼20% for 10‐cm tall grassland to over 60% for the dense soybean field. At 5 GHz the corresponding reduction in sensitivity ranged from ∼70% to ∼90%.

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