Education Never Stops [President's Column]

The Brain Never Stops

THE BRAIN IS SPONTANEOUSLY ACTIVE Surprisingly, the brain uses about 20% of the body’s energy at all times. That’s right: about one-fifth of everything you eat is for your brain. Figure 1 shows the energy consumption of the upper body and head. The dark areas show body parts that use a lot of energy while resting without movement. The brain uses a lot of energy, so it appears very dark in the i...

Presidents, Vice Presidents, and Death: Closing the Constitution's Succession Gap

Simulating a Shared Register in a System that Never Stops Changing

Simulating a shared register can mask the intricacies of designing algorithms for asynchronous message-passing systems subject to crash failures, since it allows them to run algorithms designed for the simpler shared-memory model. Typically such simulations replicate the value of the register in multiple servers and require readers and writers to communicate with a majority of servers. The succ...

Underwriting the presidents.

The United States has had 43 presidents. We examined whether they survive significantly longer or shorter than their contemporaries. We found that survival was better for presidents elected in the 1789-1841 and 1933-2001 periods (SMRs of 0.7 and 0.6, respectively), but worse for those elected in 1845-1929 (SMR = 2.9). We also found increased mortality during the years lived in office (SMR = 1.4...

Presidents who value science.

www.sciencemag.org SCIENCE VOL 323 13 FEBRUARY 2009 843 COVER An image of Mare Moscoviense on the lunar farside, taken by the Terrain Camera aboard the SELENE (Kaguya) spacecraft on 17 January 2008. Crater frequency distributions derived from such images yield ages of about 2.5 billion years for several volcanic deposits in this mare, indicating that volcanism on the lunar farside lasted about ...