Body temperature daily rhythm adaptations in African savanna elephants (Loxodonta africana)

The savanna elephant is the largest extant mammal and often inhabits hot and and environments. Due to their large size, it might be expected that elephants have particular physiological adaptations, such as adjustments to the rhythms of their core body temperature (T-b) to deal with environmental challenges. This study describes for the first time the T-b daily rhythms in savanna elephants. Our results showed that elephants had lower mean T-b values (36.2 +/- 0.49 degrees C) than smaller ungulates inhabiting similar environments but did not have larger or smaller amplitudes of T-b variation (0.40 +/- 0.12 degrees C), as would be predicted by their exposure to large fluctuations in ambient temperature or their large size. No difference was found between the daily T-b rhythms measured under different conditions of water stress. Peak T-b's occurred late in the evening (22: 10) which is generally later than in other large mammals ranging in similar environmental conditions. (C) 2007 Elsevier Inc. All rights reserved.

The effects of season and dietary salt content on body temperature daily rhythms of common spiny mice from different micro-habitats

We compared body temperature (T-b) daily rhythms in two populations of common spiny mice, Acomys cahirinus, during summer and winter months in relation to increasing dietary salt content. Mice were collected from the North and South facing slopes (NFS and SFS) of the same valley, that are exhibiting mesic and xeric habitats, respectively. During the summer, whilst mice were offered a water source containing 0.9% NaCl, SFS individuals had T-b peak values at 24:00, whereas NFS individuals had peak values at 18:00. When the salinity of the water source was increased, from 0.9 to 2.5% and then 3.5%, the difference between maximal and minimal T-b of both populations increased. In addition, with increased salinity, the T-b daily peak of SFS mice shifted to 18:00. During the winter, the mean daily T-b values of both populations of mice were lower than during the summer. At 0.9% salinity, the NFS mice exhibited a daily T-b variation with a peak at the beginning of the night. However, we did not detect any significant variation in daily T-b in the SFS mice. At 2.5% salinity, the difference between the mean daily T-b of mice from the two slopes increased. In winter we were unable to increase the salinity to 3.5% as the animals began to lose weight rapidly. We suggest that common spiny mice that inhabit these two micro-habitats axe forming two discrete populations that respond differently to the environmental pressures prevailing in each habitat, by evolving different physiological capacities. (C) 2002 Elsevier Science Inc. All rights reserved.

A randomized controlled trial of tea tree oil (5%) body wash versus standard body wash to prevent colonization with methicillin-resistant Staphylococcus aureus (MRSA) in critically ill adults: research protocol

Background
Over the past ten years MRSA has become endemic in hospitals and is associated with increased healthcare costs. Critically ill patients are most at risk, in part because of the number of invasive therapies that they require in the intensive care unit (ICU). Washing with 5% tea tree oil (TTO) has been shown to be effective in removing MRSA on the skin. However, to date, no trials have evaluated the potential of TTO body wash to prevent MRSA colonization or infection. In addition, detecting MRSA by usual culture methods is slow. A faster method using a PCR assay has been developed in the laboratory, but requires evaluation in a large number of patients.

Methods/Design
This study protocol describes the design of a multicentre, phase II/III prospective open-label randomized controlled clinical trial to evaluate whether a concentration of 5% TTO is effective in preventing MRSA colonization in comparison with a standard body wash (Johnsons Baby Softwash) in the ICU. In addition we will evaluate the cost-effectiveness of TTO body wash and assess the effectiveness of the PCR assay in detecting MRSA in critically ill patients. On admission to intensive care, swabs from the nose and groin will be taken to screen for MRSA as per current practice. Patients will be randomly assigned to be washed with the standard body wash or TTO body wash. On discharge from the unit, swabs will be taken again to identify whether there is a difference in MRSA colonization between the two groups.

Discussion
If TTO body wash is found to be effective, widespread implementation of such a simple colonization prevention tool has the potential to impact on patient outcomes, healthcare resource use and patient confidence both nationally and internationally.

Trial Registration
[ISRCTN65190967]

Spontaneous transitions in the coordination of a whole body task

This paper describes an example of spontaneous transitions between qualitatively different coordination patterns during a cyclic lifting and lowering task. Eleven participants performed 12 trials of repetitive lifting and lowering in a ramp protocol in which the height of the lower shelf was raised or lowered I cm per cycle between 10 and 50 cm. Two distinct patterns of coordination were evident: a squat technique in which moderate range of hip, knee and ankle movement was utilised and ankle plantar-flexion occurred simultaneously with knee and hip extension; and a stoop technique in which the range of knee movement was reduced and knee and hip extension was accompanied by simultaneous ankle dorsi-flexion. Abrupt transitions from stoop to squat techniques were observed during descending trials, and from squat to stoop during ascending trials. Indications of hysteresis was observed in that transitions were more frequently observed during descending trials, and the average shelf height at the transition was 5 cm higher during ascending trials. The transitions may be a consequence of a trade-off between the biomechanical advantages of each technique and the influence of the lift height on this trade-off. (C) 2001 Elsevier Science B.V. All rights reserved.

Testing the palaeoclimatic significance of the Northern Irish bog oak record

We present an analysis of the Northern Irish bog oak record presented in Turney et al. (2005) for the last 4500 years. The record is compared with a compiled peatland water table record from the same region and palaeohydrological data from northern England and mid-latitude Europe. It is apparent that there is no consistent relationship between the population frequency of Irish bog oaks and the palaeohydrological reconstructions, illustrating that the record is not reflecting wetness changes in peatlands. We suggest that the bog oaks should be scrutinised on a within-site and a site-by-site basis to assess the spatial coherency of the shifts in tree populations and the synchronicity of phases of germination and dying off (GDO). Further work is needed to critically examine the controls on the establishment and demise of bog oaks on Irish peatlands before these data can be used as a palaeoclimate proxy. Only then can they be used to test solar forcing of Holocene climate change.