An arsenic(III)-oxidizing bacterial population: selection, characterization, and performance in reactors.

Aims: To select an autotrophic arsenic(III)-oxidizing population, named CASO1, and to evaluate the performance of the selected bacteria in reactors.

Methods And Results: An As(III)-containing medium without organic substrate was used to select CASO1 from a mining environment. As(III) oxidation was studied under batch and continuous conditions.

Occurrence and identification of microorganisms in compacted clay-based buffer material designed for use in a nuclear fuel waste disposal vault.

A full-scale nuclear fuel waste disposal container experiment was carried out 240 m below ground in an underground granitic rock research laboratory in Canada. An electric heater was surrounded by buffer material composed of sand and bentonite clay and provided heat equivalent to what is anticipated in a Canadian nuclear fuel waste repository. During the experiment, the heat caused a mass transport of water and moisture content gradients developed in the buffer ranging from 13% closest to the heater to 23% at the rock wall of the deposition hole.

Fungal colonization of the esophagus.

A prospective study was conducted in 224 patients to determine the clinical significance of esophageal colonization with yeasts under different conditions. In accordance with the results of direct smear microscopic examination and culture of esophageal brushings, patients were divided into three groups: positive, negative, and the patients, in whom saprophytic forms were detected. A higher prevalence of positive findings was noted in patients with predisposing factors for yeast invasion than in patients free of underlying disease.