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Cytokines regulate inflammation associated with cardiopulmonary bypass (CPB). Pro-inflammatory cytokines may cause myocardial dysfunction and haemodynamic instability after CPB, but the release of anti-inflammatory cytokines is potentially protective. We studied the effects of dexamethasone on pro- and anti-inflammatory cytokine responses during coronary artery bypass grafting surgery.

Two groups of six mature brushtail possums (Trichosurus vulpecula) were housed in two respiration chambers, and their heat production, whole body conductance and lower critical temperatures were measured under a variety of simulated weather patterns. The possums were subjected to ambient temperatures of 30, 20 and 3 °C. At 20 and 3 °C, the animals were exposed to near still air and light winds (wind speed 0.8 and 6.7 km/h), both with, and without, simulated rain every 8 hours. The lower critical temperature in near still air lies between 7 and 10 °C. This temperature increases by about 2, 6 and 8 °C respectively for a wind velocity of 6.7 km/h, simulated rain and a combination of the two factors. Weather in New Zealand, especially in the cooler part of the year, will often produce conditions below the lower critical temperature of the thermoneutral zone of possums. This will necessitate significant increases in metabolic rate and hence food consumption or mobilisation of body fat reserves, which if not sustainable will result in the death of possums. Field studies have shown that this is often the case in the wild. It is proposed that this stress may be sufficient to decrease the resistance (especially cell-mediated immunity) of some possums and allow acceleration of the disease process in those infected with Mycobacterium bovis.

Antarctic continental shelf waters are poorly sampled, particularly beneath sea ice during winter. Profiling floats could help fill this gap, but floats are unable to surface to obtain a satellite position when ice is present. We deployed Argo profiling floats in a coastal polynya with a novel mission to rest on the sea floor between profiles. “Parking” on the seabed minimized the drift of the floats and allowed year‐round, full‐depth measurements over multiple winters. Measurements of water depth derived from the floats were used in combination with known bathymetry to constrain the position of profiles collected under ice. Errors were quantified by withholding known positions and comparing them to estimated positions; the bathymetrically constrained algorithm outperformed linear interpolation. A similar approach could potentially be used to geolocate other under‐ice oceanographic platforms that measure water depth. The seasonal ice zone of the Antarctic continental shelf is one of the largest “blind spots” in the global oceans. Profiling float measurements can help fill this gap; however, sea ice prevents the floats from surfacing and obtaining a position from satellites. This reduces the utility of these data to the oceanographic community. We deployed floats in a novel way to rest on the seabed between profiles. “Parking” on the seabed helped retain the floats on the continental shelf and also provided measurements of sea floor depth as well as water properties. We used the water depths measured by the floats and knowledge of seabed bathymetry to estimate the position of the float profiles. The new approach offers significant improvement over the usual approach of linear interpolation and could potentially be used to navigate other oceanographic instruments under ice. Sea ice prevents profiling floats from surfacing and obtaining a position from navigation satellites, reducing the utility of observationsFloats programmed to park on the seabed between profiles provide year‐round, full‐depth profiles in an Antarctic continental shelf polynyaFloat measurements of pressure at the seabed were used in combination with known bathymetry to estimate the location of under‐ice profiles