Towards a rain-dominated Arctic

Climate models project a strong increase in Arctic precipitation over the coming century1, which has been attributed primarily to enhanced surface evaporation associated with sea-ice retreat2. Since the Arctic is still quite cold, especially in winter, it is often (implicitly) assumed that the additional precipitation will fall mostly as snow3. However, little is known about future changes in the distributions of rainfall and snowfall in the Arctic. Here we use 37 state-of-the-art climate models in standardized twenty-first-century (2006–2100) simulations4 to show a decrease in average annual Arctic snowfall (70°–90° N), despite the strong precipitation increase. Rain is projected to become the dominant form of precipitation in the Arctic region (2091–2100), as atmospheric warming causes a greater fraction of snowfall to melt before it reaches the surface, in particular over the North Atlantic and the Barents Sea. The reduction in Arctic snowfall is most pronounced during summer and autumn when temperatures are close to the melting point, but also winter rainfall is found to intensify considerably. Projected (seasonal) trends in rainfall and snowfall will heavily impact Arctic hydrology (for example, river discharge, permafrost melt)5, 6, 7, climatology (for example, snow, sea-ice albedo and melt)8, 9 and ecology (for example, water and food availability)5, 10

Can vibrational playback improve control of an invasive stink bug?

Improved understanding of the function of insect vibrational signals has spurred development of a vibrational method for mass-trapping the brown marmorated stink bug, which is currently one of the most notorious invasive insect pests. We outline the ongoing research program, which started with the basic description of close-range sexual behaviour that is mediated by vibrational signals, and continued with testing of a promising female vibrational signal that proved to be considerably attractive to males in playback trials. On this basis, a bi-modal trap was constructed, comprising an aggregation pheromone dispenser, the vibrational signal playback and a device for electrocuting the attracted animals in a pyramid trap design. Preliminary field trial results are discussed in the context of the interplay between chemical and vibrational modalities during reproductive behaviour in stink bugs, and the potential for achieving environmentally friendlier control of this pest

Bisphosphonate Delivery to Tubular Bone Allografts

Large structural allografts used for reconstruction of bone defects after revision arthroplasty and tumor resection fracture up to 27% of the time from osteolytic resorption around the fixation screw holes and tendon or ligament attachment sites. Treating structural allografts before implantation with bisphosphonates may inhibit local osteoclastic processes and prevent bone resorption and the development of stress risers, thereby reducing the long-term fracture rate. Taking advantage of allografts’ open-pore structure, we asked whether passive soaking or positive-pressure pumping was a more efficient technique for delivering bisphosphonates. We treated matched pairs of ovine tibial allografts with fluids containing Tc-99m pamidronate and toluidine blue stain to facilitate indicator distribution analysis via microSPECT-microCT imaging and light microscopy, respectively. Surfactants octylphenoxy polyethoxy ethanol or beractant were added to the treatment fluids to reduce flow resistance of solutions pumped through the allografts. Indicator distribution after 1 hour of soaking produced a thin ring around periosteal and endosteal surfaces, while pumping for 10 minutes produced a more even distribution throughout the allograft. Flow resistance was reduced with octylphenoxy polyethoxy ethanol but unaffected with beractant. Pumped allografts displayed a more homogeneous indicator distribution in less time than soaking while surfactants enhanced fluid movement