Flipper beat frequency and amplitude changes in diving green turtles, Chelonia mydas

Using a turtle-borne camera system, changing flipper beat frequency and amplitude were measured in five diving green turtles (Chelonia mydas Linnaeus 1758) in the Bahía de los Angeles, Mexico (28°58′N, 113°33′W). These observations were made between June and August 2002. Turtles worked hardest (i.e., had the highest flipper beat frequency and amplitude) at the start of descents when positive buoyancy is predicted to oppose their forward motion. During the later part of descents, turtles worked less hard in line with opposing buoyancy forces being reduced. For example, flipper beat frequency declined from about 60–80 beats min−1 at the start of descent to around 25–40 beats min−1 after 30 s of the descent. At the start of ascents the flipper beat frequency was around 30 beats min−1, lower than on descent, and declined as the ascent progressed with often passive gliding for the final few meters to the surface. This pattern of effort during diving appears to apply across a range of marine reptiles, birds and mammals suggesting that graded effort during descent and ascent is an optimum solution to minimising the cost of transport during diving.

Hospital readmission among older adults with congestive heart failure

Older adults with congestive heart failure [CHF] are likely to experience multiple readmissions to hospital. There have been several studies conducted on hospital readmissions; however, generalising the findings is problematic due to the use of variable definitions of what constitutes a readmission. This paper addresses the absence of Australian research comparing groups of older patients with CHF who are readmitted to hospital with those who are not readmitted. It also adopts one of the more frequently used definitions of readmission to aid in future comparability of research. Using a comparative cohort design, a multivariate logistic regression model was used to compare readmitted patients with non-readmitted patients and identify risk factors associated with readmission. Significant risk factors identified were male gender, numerous diagnoses, lengths of stay of 3 days or longer and admission from acute, subacute or aged care facilities. The increased likelihood of readmission among patients from acute, subacute and aged care services warrants further investigation.

Instant rivalry: the Melbourne Victory versus Melbourne Heart derby

The Australian A-League football (soccer) competition only began in 2005 after a major reconstruction of the governance of the game. The model adopted was one team per city so local derbies, often the focus of intense and long-running rivalries in football overseas, did not exist. In 2010 a second team began in Melbourne where previously Melbourne Victory had a monopoly. Within a couple of seasons an intense local rivalry has developed attracting over 40,000 fans to games between Victory and newcomer Melbourne Heart. This is the story of that rivalry and how it has become one of the most eagerly anticipated sporting occasions in a country where historically soccer has been a minority sport.