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In the spring of 1995, 24 samples were collected from a widely distributed system of municipal water wells in Albuquerque, N.M., and analyzed for hydrogen (deltaD) and oxygen (delta18O) isotopic compositions. DeltaD values for 15 of these samples are largely similar to those reported by Yapp in 1985, but have locally become more negative by as much as 5 per mil (%). DeltaD--delta18O data define two end-members that are well aligned along the familiar meteoric water line (MWL): (1) the eastern domain (mountain precipitation runoff), having deltaD > - 86% (similar to the criteria of Yapp) and delta18O > - 12.1% (this work); and (2) a central basin domain, which may be in part derived from water seepage from the Rio Grande, having deltaD < - 95% and delta18O < - 13.2%. Only afew wells across the basin have deltaD values near the 'baseline' value of the Rio Grande, defined by Yapp as - 92%. The proximity of these wells to the Rio Grande is consistent with recharge by seepage from the river bed under baseline conditions. Extensive pumping in the eastern domain and West Mesa areas may be partly responsible for an apparent expansion of the central-basin regime of water more depleted in deltaD, much as a plume migrating in response to transient perturbations in original hydraulic gradients. Vertically stacked groundwateroccurrences having limited interconnection are inferred from the significant differences in isotopic compositions of samples from two wells screened at multiple depths. The central and western parts of the basin are little influenced by contributions from the eastern domain.Some groundwaters from the western part of the basin plot below the MWL and clearly cannot be mixtures solely of the eastern domain and central basin endmembers. The origins of these Western groundwaters and the most depleted central basin groundwaters are as yet unknown, but we speculate they may have received recharge under climatic conditions [ABSTRACT FROM AUTHOR]

Diazepam in a dose of 0.05 mg/kg was studied to determine its effect on a subsequently administered dose of 1 mg/kg of succinylcholine. This dose of diazepam prior to succinylcholine (1) significantly diminished the incidence of postoperative muscle pain; (2) decreased the usual increase in serum potassium; (3) did not prevent the rise in creatine phosphokinase; (4) reduced the incidence of muscle fasciculation; and (5) did not affect the magnitude or duration of the succinylcholine neuromuscular block. It was concluded that diazepam had several advantages over d-tubocurarine in the prevention of succinylcholine-induced muscle pain.