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ABSTRACT An experimental investigation was carried out to assess the durability of self-consolidating concretes (SCCs) and ordinary concretes (OCs) under sodium sulfate and sodium sulfate/sodium chloride combined solutions. A wet/drying [...]

The relative cost-effectiveness of proton-pump inhibitors (PPIs) in the maintenance therapy of erosive reflux esophagitis was studied. Decision analysis was used to model the cost-effectiveness of PPIs on the basis of clinical trial results. Management decisions in the model were based on published U.S. guidelines and recommendations. Probability estimates were derived from a systematic review of the literature. The model's base-case scenario compared rabeprazole, lansoprazole, and omeprazole for the prevention of symptom recurrence over one year. Meta-analyzed estimates of efficacy were derived from trials by using a generalized logistic regression model with random effects. Medical costs for hospitalization, procedures, and office visits reflected 2000 Medicare payment; drug costs were based on 2000 average wholesale prices. Average costs per patient were comparable among the PPIs (rabeprazole, $1414; lansoprazole, $1671; and omeprazole, $1599). Rabeprazole prevented symptom recurrence in 86% of rabeprazole recipients, versus 68% for lansoprazole and 81% for omeprazole, and yielded the lowest average cost-effectiveness ratio (rabeprazole, $1637 per recurrence prevented; lansoprazole, $2439; and omeprazole, $1968). The model was robust to changes in key variables. When evaluated by decision analysis over a wide range of assumptions, rabeprazole was comparable to other PPIs in terms of cost and offered improved effectiveness for maintenance therapy of erosive reflux esophagitis.

Abstract: 5-(4-Pyridyl)nonane has been evaluated as a solvent for trace amounts (<5·10–5 M) of tungsten(VI) from aqueous chloride-thiocyanate solutions. Remarkable enhancements in metal extractability are observed on the addition of SCN– to aqueous hydrochloric acid solutions. Extremal partition coefficients are obtained from 0.1 M HCl in 0.2 M KSCN. Diminutions of the metal extractability are produced by relatively high (>0.5 M) SCN– concentrations and increased concentration of the supporting acid. Slope analysis data, under optimal parameters, indicates the most probable composition of the extractable species as WO2(SCN)2·2PYN. Neutral anions do not have any significant effect on the D values. Behaviour of a number of metal ions has been checked using optimal aqueous conditions of extraction. The investigation shows that the reagent has a great potential for the preconcentration of a number of metal ions including the common toxins.

The coordinated MeCN in (I) is replaced completely by Py or NH3, whereas only one NMe3ligand is coordinated to Fe in the five‐coordinate cation (V) under similar conditions.