New classes of tests for the Weibull distribution using Stein's method in the presence of random right censoring.

We develop two new classes of tests for the Weibull distribution based on Stein's method. The proposed tests are applied in the full sample case as well as in the presence of random right censoring. We investigate the finite sample performance of the new tests using a comprehensive Monte Carlo study. In both the absence and presence of censoring, it is found that the newly proposed classes of tests outperform competing tests against the majority of the distributions considered. In the cases where censoring is present we consider various censoring distributions. Some remarks on the asymptotic properties of the proposed tests are included. We present another result of independent interest; a test initially proposed for use with full samples is amended to allow for testing for the Weibull distribution in the presence of censoring. The techniques developed in the paper are illustrated using two practical examples.

Electrophoretic separation and molecular weight characterization of Pseudomonas aeruginosa H-antigen flagellins.

We found that preparations of Pseudomonas aeruginosa flagellar antigens protected against P. aeruginosa challenge in a burned-mouse model. To determine the extent of similarity among known flagellar antigen types, we compared flagellins by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. A majority of our laboratory strains and clinical isolates, including PAO strains and their derivative mutants RM46 and PJ108, as well as virulent strains M-2 and 1244, had flagellins of 53,000 Mr. These flagellins had the same Mrs as those of type b-standard strains 170001 and 15084. The heterogeneous group of a-type H-antigen flagellins were of smaller molecular weights, ranging from 52,000 Mr for standard strain 5939 (a0, a3) to 45,000 Mr for standard strain 170018 (a0, a3, a4). Standard strains 5933 (a0, a1, a2) and 5940 (a0, a2) had intermediate Mrs of 51,000 and 47,000, respectively. Differences in Mr of 1,000 to 2,000 could be resolved by coelectrophoresis. A series of 26 unknown strains were categorized. Correlations among typing by molecular weight, cross-agglutination reactions with O-adsorbed H antisera, and previous results for H-serum typing are reported.

Survival of coliform bacteria in static compost piles of dairy waste solids intended for freestall bedding.

Dairy waste solids separated from a slurry by a centrifugal separator were composted in 12 static piles. Seven of the compost piles were naturally aerated, and five were aerated by a fan that forced air through the piles of solids. The natural aeration process aged the manure solids in an unconfined pile. The fan in the forced aeration process forced air into a perforated plenum beneath the compost piles. Dairy waste solids in each compost pile were heated into the thermophilic temperature range and generally composted well. At most sampling points, coliform bacteria declined to low or undetectable numbers early in the composting period. However, as the composting process proceeded, bacterial numbers increased to approximately those present in raw dairy waste solids. Findings of this study suggest that composting offers little benefit toward net reduction in coliform bacterial numbers in dairy waste solids.