We tested the hypothesis that different minerals in soil select distinct bacterial communities in their microhabitats. Mica (M), basalt (B) and rock phosphate (RP) were incubated separately in soil planted with Trifolium subterraneum, Lolium rigidum or left unplanted. After 70 days, the mineral and soil fractions were separated by sieving. Automated ribosomal intergenic spacer analysis was used to determine whether the bacterial community structure was affected by the mineral, fraction and plant treatments. Principal coordinate plots showed clustering of bacterial communities from different fraction and mineral treatments, but not from different plant treatments. Permutational multivariate anova (permanova) showed that the microhabitats of M, B and RP selected bacterial communities different from each other in unplanted and L. rigidum, and in T. subterraneum, bacterial communities from M and B differed (P<0.046). permanova also showed that each mineral fraction selected bacterial communities different from the surrounding soil fraction (P<0.05). This study shows that the structure of bacterial communities in soil is influenced by the mineral substrates in their microhabitat and that minerals in soil play a greater role in bacterial ecology than simply providing an inert matrix for bacterial growth. This study suggests that mineral heterogeneity in soil contributes to the spatial variation in bacterial communities.

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The purpose of this study was t o determine if judgments of expert piano performances would be affected by excerpt duration, non-musical attributes of performer attractiveness, dress, and stage behavior, and by an interaction between duration and these attributes. Given that non-musical attributes would be evident from the beginning of a performance but that information about performance quality would accrue with time spent listening, it was hypothesized that nonmusical attribute biases would weaken with increasing excerpt length. Thirty-three undergraduate and graduate music majors rated performers on nonmusical attributes by observing performers with the sound turned off. One hundred fourteen participants rated 15 performances on 6 test items, either under an audioonly condition or under an audiovisual condition. Excerpts were 25, 55, and 11 5 seconds. Results showing that high-attractive women held an advantage over low-attractive women for 25-second excerpts but not for longer ones confirmed the hypothesis that the importance of attractiveness declines with increased musical exposure. This hypothesis was less strongly supported for ratings of male performers, for whom differences in dress appeared t o be of greater import. It was also found that there was significantly greater agreement between test items within excerpt durations than across them. Ratings were higher at 55 seconds and 11 5 seconds than they were at 25 seconds, although reliability declined slightly as excerpts became longer. Finally, performances judged underthe audiovisual condition were rated significantly higher than performances judged under the audio-only condition.

The purpose of this study war to determine how judgments of solo performances rpcorded at an internationalpiano coinpetition might be affeed by excerpt duration (20 uersus 60 seconds) and tempo (slow versus f a t ) . Musicians rated perfonmiices on six test item. Results indicated that piano majors rated slow exceqts higher than t h g rated fart excerpts, and that t h g rated slow excerpts higherthan nonpiano majors rated either slow or fast excerpts; undergraduates rated long excerpts the same as or slightly higher than thqr did short excerpts, but graduate students and faculty rated long excerpts markedly higher than short excerpts; and undeqpduate piano majors rated performances lower than did undergraduate nonpiano majors, but graduate piano m a j m and facuIty rated performances higher than did graduate/faculty nonpiano majors. Also, accuracy i t e m correlated Witia each other morz high4 than fhqr did with other item.s, and judge ratings were higher for accuracy i t e m than thqr were for other item. Finally, judge consisten9 was shown to be related to excerpt duration, excerpt tempo, instrumental majol; and level of education. Results generally show that ratings taken aJer 60 seconds differed frvin ratings taken after 20 seconds, and that ratings prvuided evidence that judges were able l o distinguish between dijjferent test items.