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A 30,000-year paleotemperature record derived from noble gases dissolved in carbon-14-dated ground water indicates that the climate in lowland Brazil (Piaui Province, 7 ° S, 41.5 ° W; altitude, 400 meters) was 5.4 ° ± .6 ° C cooler during the last glacial maximum than today. This result suggests a rather uniform cooling of the Americas between 40 ° S and 40 ° N. A 5.4 ° C cooling of tropical South America is consistent with pollen records, snow line reconstructions, and strontium/calcium ratios and [σ.sup.18]O coral records but is inconsistent with the sea-surface temperature reconstruction of CLIMAP (Climate: Long-Range Investigation, Mapping and Prediction). On the basis of these results, it appears that the tropical Americas are characterized by a temperature sensitivity comparable to that found in higher latitudes., Whether the tropical regions were stabilized at current temperatures is a central issue in paleoctimate research. The hypothesis that the tropics may be characterized by stable temperatures rests primarily on [...]

A high-performance liquid chromatographic method for the determination of the free excreted anabolic drug methandienone in pharmacokinetic studies is described. After extraction of the free steroids from urine, separation on reversed-phase columns leads to quantitative determination of this drug down to 5 ng, and to qualitative detection of less than 1 ng amounts. Because the anabolic drugs and their metabolites are eluted later than the other normally excreted constituents this method is also useful for the routine surveillance of anabolic drug abuse in the sports in general.