This relationship was stronger in single nestlings than in birds from multiple-chick broods, which suggests a greater impact of Pb on more stressed individuals.
The interaction term Pb ×brood size was also significant (F1,20 = 7.30; p = 0.014), suggesting that Pb had a greater effect on the stress-induced corticosterone of single nestlings than on those of multiple-chick broods (Table 2, Figure 1).
In the present study we also found that the association between Pb and the stress-induced response was greater for birds from single-chick broods than for those from multiple-chick broods.
Brood size was categorized as either single- (one-chick nests) or multiple-chick broods (two- or three-chicks nests), because we found no differences in either baseline or stress-induced corticosterone levels between nestlings from two- and three-chick nests (Blas et al. 2005).
Maximum corticosterone concentration was positively related to blood Pb levels (F1,20 = 10.93; p = 0.004; Table 2) in both colony locations (interaction term, Pb ×colony, F1,19 = 0.58; p = 0.456), and singletons had higher levels of corticosterone (53.3 ± 14.6 ng/mL; n = 10) than nestlings from multiple-chick broods (42.9 ± 9.3 ng/mL; n = 48; F1,20 = 5.36; p = 0.031; Table 2).
Here we show that biophysical stimuli generated by muscle contractions impact multiple events during chick knee joint morphogenesis influencing differential growth of the skeletal rudiment epiphyses and patterning of the emerging tissues in the joint interzone.
The action centres on Chicklet, a Gidget-esque surfer chick with multiple personality disorder, and a horrifying spate of serial pubic hair shavings.
Add to this thematic weight the fact that Pynchon invokes the tones of multiple genres – detective story, chick lit, teen lit, sci-fi, Tom Wolfean social satire – and the fact that it takes almost 500 pages, most of them frantic with pop-culture references, to unfold, and a sense emerges of the scale of investment Pynchon demands from his reader.
Interestingly, while in the mouse the blood island appears as a single belt-like structure encompassing the yolk sac [ 1], blood islands in the chick represent multiple more distinct clusters of cells.
Grand mean average waves (with 95% confidence intervals) from the ERG recordings were obtained by averaging across the multiple recordings from the chicks in the DMSO and ouabain groups 4 days post injection.
Golden, J.A. & Cepko, C.L. Clones in the chick diencephalon contain multiple cell types and siblings are widely dispersed.
