Home-range sizes and bower visitation patterns of immature male Satin Bowerbirds (Ptilonorhynchus violaceus)

Adult male Satin Bowerbirds build and decorate stick bowers to which they attract females for matings; females choose among males based on these complex bowers, decorations placed at these bowers, and displays consisting of vocalisations and posturing. Male Satin Bowerbirds undergo an extended period of delayed morphological maturation during which they retain female-like plumage and are assumed to learn adult male behavioural traits. Little is known, however, of how immature males acquire the ability to display and build and decorate bowers, except that they observe the displays of adult males at adults' bowers, and practise their own displays at both adults' and 'practice' bowers. We present data on the home ranges and movement patterns of six immature males, acquired through radio-tracking at the Bunya Mountains in south-east Queensland. Home-range size averaged 13.67 +/- 3.38 ha and immature males visited only some of the bowers located in their home ranges. On average, they visited 2.33 +/- 0.52 adults' bowers and 4.00 +/- 2.00 practice bowers.

Determination of domain sizes in blends of poly(ethylene) and poly(styrene) formed in the presence of supercritical carbon dioxide

Well-mixed blends of poly(ethylene) and poly(styrene) have been synthesized using supercritical carbon dioxide as a solvent. The morphology of the blends has been conclusively characterized using differential scanning calorimetry (DSC), small-angle X-ray scattering (SAXS), Raman microprobe microscopy, and C-13 solid-state cross-polarization magic angle spinning NMR (C-13 CPMAS NMR). DSC measurements demonstrate that poly(styrene) in the blends resides solely in the amorphous regions of the poly(ethylene) matrix; however, corroborative evidence from the SAXS experiments shows that poly(styrene) resides within the interlamellar spaces. The existence of nanometer-sized domains of poly(styrene) was shown within a blend of poly(styrene) and poly(ethylene) when formed in supercritical carbon dioxide using Raman microprobe microscopy and C-13 CPMAS NMR spectroscopy coupled with a spin diffusion model. This contrasts with blends formed at ambient pressure in the absence of solvent, in which domains of poly(styrene) in the micrometer size range are formed. This apparent improved miscibility of the two components was attributed to better penetration of the monomer prior to polymerization and increased swelling of the polymer substrate by the supercritical carbon dioxide solvent.