RESUMO
The existence of a spatially varying texture in superfluid ^{3}He is a direct manifestation of the complex macroscopic wave function. The real space shape of the texture, namely, a macroscopic wave function, has been studied extensively with the help of theoretical modeling but has never been directly observed experimentally with spatial resolution. We have succeeded in visualizing the texture by a specialized magnetic resonance imaging. With this new technology, we have discovered that the macroscopic chiral domains, of which sizes are as large as 1 mm, and corresponding chiral domain walls exist rather stably in ^{3}He-A film at temperatures far below the transition temperature.
RESUMO
Legionella spp., the causative organism of legionnaires' disease, were isolated from more than 80% of water samples in cooling towers before washing. Therefore, we evaluated the effect of microbicide treatment of cooling tower water on Legionella spp., other bacteria and protozoa. 2-Bromo-2-nitropane-1,3-dial, 2,4-dibromo-5,5-dimethylhydantoin or silver nitrate-treated silica gel was added to cooling tower water. The isolation rate of Legionella spp. in the cooling tower water was 50% after microbiocide treatment with 2-bromo-2-nitropane-1,3-dial being the most effective. The microbicide treatment had no effect on other bacteria or protozoa. These findings indicated the importance of regular washing and water exchange of cooling tower water with microbicide treatment.
