Spatially explicit poisoning risk affects survival rates of an obligate scavenger

Obligate scavengers such as vultures provide critical ecosystem services and their populations have undergone severe declines in Asia and Africa. Intentional poisoning is a major threat to vultures in Africa, yet the impact on vulture populations of where poisoned carcasses are positioned is not known. We used re-sightings of 183 African white-backed vultures captured and tagged in two regions of South Africa, some 200 km apart, to estimate spatial differences in relative survival rates across life stages. Juvenile survival rates were similar in the two regions, whilst subadult and adult survival rates differed significantly. Using agent-based modelling, we show that this pattern of relative survival rates is consistent between regions that differ in intensity of poisoning, despite the proximity of the two regions. This may have important consequences for vulture conservation and the targeting of conservation efforts, particularly with regard to the efficacy of “vulture safe zones” around vulture breeding populations

Lawson criterion for ignition exceeded in an inertial fusion experiment

For more than half a century, researchers around the world have been engaged in attempts to achieve fusion ignition as a proof of principle of various fusion concepts. Following the Lawson criterion, an ignited plasma is one where the fusion heating power is high enough to overcome all the physical processes that cool the fusion plasma, creating a positive thermodynamic feedback loop with rapidly increasing temperature. In inertially confined fusion, ignition is a state where the fusion plasma can begin "burn propagation" into surrounding cold fuel, enabling the possibility of high energy gain. While "scientific breakeven" (i.e., unity target gain) has not yet been achieved (here target gain is 0.72, 1.37 MJ of fusion for 1.92 MJ of laser energy), this Letter reports the first controlled fusion experiment, using laser indirect drive, on the National Ignition Facility to produce capsule gain (here 5.8) and reach ignition by nine different formulations of the Lawson criterion

Glial and neuronal dysfunction in streptozotocin-induced diabetic rats

C1 - Journal Articles RefereedNeuronal dysfunction has been noted very soon after the induction of diabetes by streptozotocin injection in rats. It is not clear from anatomical evidence whether glial cell dysfunction accompanies the well-documented neuronal deficit. Here, we isolate the Müller cell driven slow-P3 component of the full-field electroretinogram and show that it is attenuated at 4 weeks following the onset of streptozotocin-hyperglycaemia. We also found a concurrent reduction in the sensitivity of the phototransduction cascade, as well as in the components of the electroretinogram known to indicate retinal ganglion cell and amacrine cell integrity. Our data support the idea that neuronal and Müller cell dysfunction occurs at the same time in streptozotocin-induced hyperglycaemia