Sensitivity analysis of a King George Island outlet glacier, South Shetlands, Antarctica.

The Lange glacier is an outlet glacier situated in the Admiralty Bay, King George Island, Peninsula Antarctica. It retreated about 1 km since the 1950s. Although recent observations do not show any significant change at the ice-ocean margin, it is not clear whether this glacier has reached a new steady state or whether it is still adjusting to new climate conditions. By combining a three-dimensional glacier model with satellite and in-situ datasets, we investigate the sensitivity of Lange glacier to perturbations in flow rate factor, friction coefficient, surface mass balance, and calving front position. The (time-dependent) perturbation experiments show that the glacier is more sensitive to changes in surface mass balance and in flow rate factor. These results suggest that the climate variability of this region plays an important role on the glacier's dynamics, and that measurements of englacial temperature will improve the reliability of future modeling efforts. Our model shows that the position of the ice front exerts a strong control on the glacier flux. In our time-dependent simulation, the impacts of the observed front retreat on the glacier's dynamics persist beyond the present date. This suggests that Lange is likely still adjusting to past perturbations at its terminus.

Three different Ge environments in a new Sr5CuGe9O24 phase synthesized at high pressure and high temperature.

In the framework of expanding the range of copper-based compounds in the pyroxene family, we have synthesized at high pressure and high temperature a powder containing a mixture of a new phase with stoichiometry Sr5CuGe9O24 having two identified impurity phases. Electron crystallography showed that the new phase crystallizes in the monoclinic space group P2/c, with unit-cell parameters a = 11.8 Å, b = 8.1 Å, c = 10.3 Šand ß = 101.3°. We applied the recently developed low-dose electron diffraction tomography method to solve the structure by direct methods. The obtained structure model contains all 9 independent cation positions and all 13 oxygen positions. A subsequent refinement against powder X-ray diffraction data ascertained the high quality of the structure solution, in particular, the unusual structural arrangement that there are three different environments for Ge in this phase.

Acute graft pyelonephritis: a potential cause of acute rejection in renal transplant.

Acute graft pyelonephritis is a common complication in renal transplant recipients. The consequences of this complication on kidney allograft survival remain controversial. Bacterial infection is likely to activate the immune system, potentially leading to acute or chronic rejection. Here, we report for the first time two documented cases of acute rejection occurring shortly after acute graft pyelonephritis, suggesting that pyelonephritis can initiate acute rejection. The immunologic process leading to the alloimmune response is discussed. These reports suggest that acute rejection should be questioned in case of atypical graft outcome in the context of acute graft pyelonephritis.