Hull Cupules of Chiton Eggs: Parachute Structures and Sperm Focusing Devices?

Sperm and scrambled eggs

A newspaper obituary not long ago revealed that its subject was believed to have been both the son and grandson of the lecherous monarch, Edward VII. (Work it out for yourself.) But this is as nothing to the conundrums that Lee Silver sets out in his mesmerizing vision of our genetic future. Within weeks of the eruption of Dolly the sheep into the pages of Nature — and regardless of the doubts ...

Beech cupules as keystone structures for soil fauna

Facilitative or positive interactions are ubiquitous in nature and play a fundamental role in the configuration of ecological communities. In particular, habitat modification and niche construction, in which one organism locally modifies abiotic conditions and favours other organisms by buffering the effects of adverse environmental factors, are among the most relevant facilitative interactions...

Focusing in Microfluidic Devices

Neck Injury Risk from Helmet Mounted Devices during Parachute Opening

Parachute opening shock tests were conducted with an instrumented test manikin to measure and record transmitted neck loads. The standard paratrooper helmet, as well as two developmental helmet systems, were fitted to the manikin head. These two systems alter the headborne weight and center of mass from the standard helmet, potentially increasing the risk of acute neck injury during parachute o...

Potential Hull Structures for Rescue and Search

Tradeoff studies between pressure hull material, configuration, and buoyancy are performed for both the Rescue and the Search Vehicles of the DeepSubmergence Systems Project. Spherical, cylindrical, and spheroidal shells of high strength steels, titanium alloys, aluminum alloys, glass-reinforced plastics, glass, and ceramics are considered. Failure criteria are developed based on recent researc...