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Can we extract a new swarm behaviour out of the sperm: Sperm swimming at low Reynolds number have strong hydrodynamic interactions when their concentration is high in vivo or near substrates in vitro. The beating tails not only propel the sperm through a

Normally we associate levitation of objects to superconducting materials. Here a new technique is shown where levitation of a whole new range of materials is shown. "The large temperature gradient leads to a force that balances gravity and results in stable levitation," said Fung, the study's lead author. "We managed to quantify the thermophoretic force and found reasonable agreement with what is predicted by theory. This will allow us to explore the possibilities of levitating different types of objects." Paper at http://aip.scitation.org/doi/10.1063/1.4974489 New microgravity experiments possibility?

not really I fear .... "Typical sizes of the trapped particles are between 10 μm and 1 mm at a pressure between 1 and 10 Torr. The trapping stability is provided radially by the increasing temperature field and vertically by the transition from the free molecule to hydrodynamic behavior of thermophoresis as the particles ascend."

Might still be OK micro to mm sized experiments. The technique seems to be reliable and cheap enough to compete with other types of microgravity approaches - more research needed to define boundaries of course.

Scientists at MIT have traced 13 billion years of galaxy evolution, from shortly after the Big Bang to the present day. Their simulation, named Illustris, captures both the massive scale of the Universe and the intriguing variety of galaxies - something previous modelers have struggled to do. It produces a Universe that looks remarkably similar to what we see through our telescopes, giving us greater confidence in our understanding of the Universe, from the laws of physics to our theories about galaxy formation. "Simulation is the future of innovation"

Awarded videos of fluid motion presented at the APS DVD meeting. Very cool stuff. #0084 is done with the setup I used for my master thesis.

Collisionless electrostatic shocks (CES) are the dominant process in heating a plasma when using high power lasers. It turns out that ion-ion collisions actually only play a small role. The ability to create small regions of very high ion energy density on time scales shorter than that of hydrodynamic expansion will be of interest in attempts to understand the processes involved in inertial confinement fusion.