Four species of tropical tree (Acacia auriculiformis Cunn. ex Benth., A. mangium Willd., A. crassicarpa Cunn. ex Benth. and Eucalyptus pellita F.Muell.) were studied at a site on Melville Island, off the north coast of the Northern Territory of Australia, in the wet–dry tropics. Rates of light-saturated assimilation were measured every 2 months, in the morning and afternoon, concurrently with gs (stomatal conductance) and microclimate (air temperature, relative humidity and photosynthetic photon flux density). Phyllodes were also sampled for subsequent nitrogen determination. Pre-dawn and diurnal phyllode water potentials were measured at the end of the wet and dry seasons. Tree height and canopy area were recorded at the end of 50 months of growth. Assimilation was found to decline substantially in the afternoon compared with the morning in the dry season but not the wet season. This was not due to diurnal declines in phyllode water potential but was attributed partially to decreased gs resulting from increased leaf-to-air vapour pressure difference. However, an interpretation of the Ci/Ca (ratio of intenal to ambient CO2 concentrations) data suggested that additional factors, other than gs, may be involved in causing the afternoon decline in assimilation rate. There was a linear relationship between pre-dawn water potential and Amax (maximum assimilation) and an inverse relationship between Amax and tree height, a result attributed to differences between species in allocation of carbon within the tree.

This study assessed the effect of mirrors on the dance performance of beginning college ballet students in the classroom setting, using an evaluation methodology developed for this study. 13 women enrolled in one ballet class were taught using mirrors, 14 women in a second beginning ballet class were taught without mirrors. Both classes were taught by the same instructor. All students were videotaped performing the same adagio and grand allegro phrase during Weeks 5 and 14 of the 14-wk. term. At the end of the semester two ballet teachers viewed the videotapes for both classes. One evaluator was the instructor, and the other was a blind reviewer who had no knowledge of which was the mirror and nonmirror class during the evaluation process. They were instructed to choose a score for each dancer with anchors of 1: low skill and 5: high skill for both the adagio and allegro phrases. High interrater reliability was noted for both the adagio and allegro phrase data. In the nonmirror class, there was a significant increase in adagio scores, but no significant increases in adagio and allegro scores for the mirror class. These results suggest that the use of the mirror in a ballet classroom may negatively affect skill acquisition of the dancer.

To examine the ability of participants from different ethnic backgrounds to accurately interpret the nonverbal behavior of European American adults, African American (n = 39), African and Afro-Caribbean (referred to as international) (n = 17), and European American (n = 38) undergraduate students completed the Diagnostic Analysis of Nonverbal Accuracy Scale (DANVA). European American participants were found to be more accurate than international and African American participants in identifying emotion in tones of voice and more accurate than international participants in identifying emotion in postures. However, the mean differences became nonsignificant when the effects of acculturation were removed. The results are discussed within the context of the convergence theory of interethnic communication described by Kincaid.

A generalization of the technique of Tubman et al. (1984) allows the inclusion of intermediate fluid layers in the theoretical study of elastic wave propagation in a layered borehole. The number and location of fluid layers are arbitrary. The only restrictions are that the central cylinder is fluid and the outermost formation is solid. Synthetic full‐waveform microseismograms in poorly bonded cased holes can be generated, allowing investigation of free pipe and cement sheathed pipe with no bond to the formation. If there is a fluid layer between the steel and the cement, the steel is free to ring. The first arrival in this situation is from the casing, even with an extremely thin fluid layer or microannulus. The amplitude and duration of the pipe signal depend upon the thickness of the fluid layer. While the first arrival is from the casing, the formation body‐wave energy is present. The character of the waveform will vary as the formation parameters vary. If the duration of the steel arrival is small, it is possible to distinguish the formation P-wave arrival. If the fluid layer is between the cement and the formation, then the steel is well bonded to the cement but the cement is not bonded to the formation. In this case the thicknesses of the fluid and cement layers are important in determining the nature of the first arrival. If there is a large amount of cement bonded to the steel, the cement can damp out the ringing of the pipe and make it possible to distinguish formation arrivals. If there is less cement bonded to the steel, the cement does not damp out the steel ringing but the cement rings along with the steel and the first arrival is from the combination of the steel and the cement. The velocity of this wave depends upon the velocities and thicknesses of the steel and cement layers.

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