Development of a time-stepping sediment budget model for assessing land use impacts in large river basins.

The use of river basin modelling to guide mitigation of non-point source pollution of wetlands, estuaries and coastal waters has become widespread. To assess and simulate the impacts of alternate land use or climate scenarios on river washload requires modelling techniques that represent sediment sources and transport at the time scales of system response. Building on the mean-annual SedNet model, we propose a new D-SedNet model which constructs daily budgets of fine sediment sources, transport and deposition for each link in a river network. Erosion rates (hillslope, gully and streambank erosion) and fine sediment sinks (floodplains and reservoirs) are disaggregated from mean annual rates based on daily rainfall and runoff. The model is evaluated in the Burdekin basin in tropical Australia, where policy targets have been set for reducing sediment and nutrient loads to the Great Barrier Reef (GBR) lagoon from grazing and cropping land. D-SedNet predicted annual loads with similar performance to that of a sediment rating curve calibrated to monitored suspended sediment concentrations. Relative to a 22-year reference load time series at the basin outlet derived from a dynamic general additive model based on monitoring data, D-SedNet had a median absolute error of 68% compared with 112% for the rating curve. RMS error was slightly higher for D-SedNet than for the rating curve due to large relative errors on small loads in several drought years. This accuracy is similar to existing agricultural system models used in arable or humid environments. Predicted river loads were sensitive to ground vegetation cover. We conclude that the river network sediment budget model provides some capacity for predicting load time-series independent of monitoring data in ungauged basins, and for evaluating the impact of land management on river sediment load time-series, which is challenging across large regions in data-poor environments.

A modified Vancouver Scar Scale linked with TBSA (mVSS-TBSA): Inter-rater reliability of an innovative burn scar assessment method.

BACKGROUND: Current scar assessment methods do not capture variation in scar outcome across the burn scar surface area. A new method (mVSS-TBSA) using a modified Vancouver Scar Scale (mVSS) linked with %TBSA was devised and inter-rater reliability was assessed. METHOD: Three raters performed scar assessments on thirty patients with burn scars using the mVSS-TBSA. Scoring on pigmentation, vascularity, pliability and height was undertaken for the 'best' and 'worst' areas of each scar. Raters allocated the total body surface area of the scar (%TBSA) to three mVSS categories (<5, 5-10, >10). Intra-class correlation coefficient (ICC) and weighted kappa statistic (kw) were used to assess inter-rater reliability. The data were also analysed for clinically relevant misclassifications between pairs of raters. RESULTS: Total mVSS scores showed 'fair to good' agreement (ICC 0.65-0.73) in the 'best' area of the scar while there was 'excellent' agreement in the 'worst' scar area (ICC 0.85-0.88). The kw of the individual mVSS components ranged from 0.44 to 0.84 and 0.02 to 0.86 for 'best' and 'worst' scar areas, respectively. Determination of scar %TBSA had 'excellent' reliability (ICC 0.91-0.96). Allocation of scar %TBSA to severity category <5 mVSS demonstrated 'good to excellent' reliability (ICC 0.63-0.80) and 'fair to good' reliability (ICC 0.42-0.74) for 5-10 mVSS category. However, misclassifications were observed for the total mVSS score in the 'worst' scar area and the allocation of scar %TBSA in the <5 mVSS category. CONCLUSION: Inter-rater reliability of mVSS scores depends on the severity of the scar area being assessed. The mVSS-TBSA method of allocation of scar %TBSA to two broad mVSS categories, namely <5 and ≥5 mVSS, has 'good to excellent' reliability. The mVSS-TBSA has demonstrated utility for both clinical and research purposes; however, there is potential to misclassify scar outcome in some cases.

The first successful parathyroid transplant from an identical twin for the cure of permanent postoperative hypoparathyroidism.

Long-lasting hypoparathyroidism is a severe disease with poor response to unsatisfactory therapy. A successful parathyroid isograft in a patient with postoperative hypoparathyroidism from an identical twin was performed in December 1984. Function was proved by the increase of serum parathyroid hormone from undetectable to normal levels, the ability to discontinue all supportive medications, and the maintenance of normal calcium homeostasis to date. The combination of hypoparathyroidism and the availability of an identical twin will be rare, but if it occurs parathyroid isografting should be considered.