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Australia’s distinctive biogeography means that it is sometimes considered an ecologically unique continent with biological and abiotic features that are not comparable to those observed in the rest of the world. This leaves some researchers unclear as to whether findings from Australia apply to systems elsewhere (or vice-versa), which has consequences for the development of ecological theory and the application of ecological management principles. We analyzed 594,612 observations spanning 85 variables describing global climate, soil, geochemistry, plants, animals, and ecosystem function to test if Australia is broadly different to the other continents and compare how different each continent is from the global mean. We found significant differences between Australian and global means for none of 15 climate variables, only seven of 25 geochemistry variables, three of 16 soil variables, five of 12 plant trait variables, four of 11 animal variables, and one of five ecosystem function variables. Seven of these differences remained significant when we adjusted for multiple hypothesis testing: high soil pH, high soil concentrations of sodium and strontium, a high proportion of nitrogen-fixing plants, low plant leaf nitrogen concentration, low annual production rate to birth in mammals, and low marine productivity. Our analyses reveal numerous similarities between Australia and Africa and highlight dissimilarities between continents in the northern vs. southern hemispheres. Australia ranked the most distinctive continent for 26 variables, more often than Europe (15 variables), Africa (13 variables), Asia (12 variables each), South America (11 variables) or North America (8 variables). Australia was distinctive in a range of soil conditions and plant traits, and a few bird and mammal traits, tending to sit at a more extreme end of variation for some variables related to resource availability. However, combined analyses revealed that, overall, Australia is not significantly more different to the global mean than Africa, South America, or Europe. In conclusion, while Australia does have some unique and distinctive features, this is also true for each of the other continents, and the data do not support the idea that Australia is an overall outlier in its biotic or abiotic characteristics.

The "Zara" exclosure (approximately 35°10'21''S, 144°41'59''E) is on a source-bordering dune on the Riverine Plain north of Deniliquin. The vegetation of this sandhill closely represents the original vegetation that once covered sandhills of the south-west Riverina prior to European occupation. Three vegetation communities comprising six associated Map Units were defined by cluster analysis within the 60 ha exclosure. These were the Callitris Mixed Woodland (Map Units 1, 2, 3, and 6), the Black Box Woodland (Map Unit 5) and the White-top Grassland (Map Unit 4). Seventy-seven taxa were recorded during the survey, and the vegetation was dominated by species from the families Chenopodiaceae and Poaceae. Three shrubs, the exotic weed Lycium ferocissimum and the natives Rhagodia spinescens and Enchylaena tomentosa occurred at more than 75% of sites. The distribution of vegetation communities was strongly associated with attributes of the soil (e.g. soil texture and organic carbon) and plant and litter cover. Vegetation communities occupying remnant sandhills such as the "Zara" exclosure are some of the most vulnerable communities on the Riverine Plain.

Introduction Transcutaneous monitoring and capnography are 2 surrogate methods of measuring arterial carbon dioxide levels employed by pediatric sleep laboratories. Both techniques are noninvasive, validated, and quantitative indirect predictors of arterial carbon dioxide level, and both have been widely adopted for use during pediatric and adult polysomnography (PSG). We hypothesized that there would be close agreement between the two techniques when compared in a pediatric population. Methods Children referred for diagnostic polysomnography to the Pediatric Sleep Laboratory at the Alberta Children's Hospital from June 2000 to October 2003 were included. All subjects underwent an overnight computerized PSG as per American Thoracic Society standards, including both transcutaneous and end-tidal monitoring. A registered PSG technician manually scored studies and eliminated all CO2 data that was not interpretable. Total "uninterpretable data" time was calculated for both channels. Statistical analysis of the level of agreement between transcutaneous and end-tidal signals was performed using a Bland-Altman analysis. Results The PSG studies of 609 children (363 males), mean age 7.9 +/- 4.6 years (range 0.1-18.4), were reviewed. On average, interpretable data was available for 61.8% +/- 35.1% and 71.5% +/- 25.2 % of total recording time from the end-tidal and transcutaneous channels respectively. The maximum and mean CO2 measurements obtained by both devices showed close agreement with a mean difference of 0.1 +/- 5.4 mm Hg and 0.6 +/- 3.9 mm Hg respectively. Conclusion Transcutaneous and end-tidal carbon dioxide monitoring during polysomnography are well tolerated and provide interpretable and comparable results in the majority of children.

We present 28 multiple sulfur isotope measurements of seawater sulfate (δ34SSO4δ34SSO4 and Δ33SSO4Δ33SSO4) from the modern ocean over a range of water depths and sites along the eastern margin of the Pacific Ocean. The average measured δ34SSO4δ34SSO4 is 21.24‰ (±0.88‰,2σ±0.88‰,2σ) with a calculated Δ33SSO4Δ33SSO4 of +0.050‰+0.050‰ (±0.014‰,2σ±0.014‰,2σ). With these values, we use a box-model to place constraints on the gross fraction of pyrite burial in modern sediments. This model presents an improvement on previous estimates of the global pyrite burial flux because it does not rely on the assumed value of δ34Spyriteδ34Spyrite, which is poorly constrained, but instead uses new information about the relationship between δ34Sδ34S and δ33Sδ33S in global marine sulfate. Our calculations indicate that the pyrite burial flux from the modern ocean is between 10% and 45% of the total sulfur lost from the oceans, with a more probable range between 20% and 35%.

Obtaining informed consent from patients considering bunion surgery can be challenging. This study assessed the efficacy of a multimedia technology as an adjunct to the informed consent process.A prospective, cohort study was conducted involving 55 patients (7 males, 48 females) who underwent a standardized verbal discussion regarding bunion correction surgery followed by completion of a knowledge questionnaire. A multimedia educational program was then administered and the knowledge questionnaire repeated. Additional supplementary questions were then given regarding satisfaction with the multimedia program.Patients answered 74% questions correctly before the multimedia module compared with 94% after it (P0.0001). Patients rated the ease of understanding and the amount of information provided by the module highly. Eighty-four percent of patients considered that the multimedia tool performed as well as the treating surgeon.Multimedia technology is useful in enhancing patient knowledge regarding bunion surgery for the purposes of obtaining informed consent.

Porous tantalum acetabular implants provide a potential solution for dealing with significant acetabular bone loss. This study reviews 24 acetabular revisions using tantalum implants for Paprosky type 3 and 4 defects. The mean Harris Hip Score improved from 35 ± 19 (range, 4-71) to 88 ± 14 (range, 41-100), p0.0001. Postoperative radiographs showed radiolucent lines in 14 hips with a mean width of 1.3 ± 1.0 mm (range, 0.27-4.37 mm). No gaps enlarged and 71% of them disappeared at a mean of 13 ± 10 months (range, 3-29 months). At a mean follow-up of 37 ± 14 months (range, 24-66 months), 22 reconstructions showed radiograpic evidence of osseointegration (92%). The two failures were secondary to septic loosening. When dealing with severe acetabular bone loss, porous tantalum acetabular components show promising short-term results.