- Number 394 |
- August 5, 2013
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Of aging bones and sunshine
Sunshine might be bad for your skin but it is good for your bones. A team of researchers working at the Advanced Light Source at DOE's Berkeley Lab has shown that the process by which bones age and become more fragile can be significantly accelerated through deficiency of vitamin D – the sunshine vitamin. Vitamin-D is essential for the body to absorb calcium. The body normally synthesizes vitamin D in the skin following exposure to sunlight – hence the “sunshine” moniker. However, when vitamin D serum concentrations become deficient, the body will remove calcium from bone to maintain normal calcium blood levels, hampering the formation of new bone mass and leading to rickets or osteomalacia. -
MOOSE fosters herd of modeling applications
Although modeling and simulation has now become standard practice in nearly every branch of science, building a useful simulation capability has been daunting because it required a team of software developers working for years with scientists to describe a given phenomenon. The MOOSE (Multiphysics Object Oriented Simulation Environment) developed at DOE's Idaho National Laboratory now enables simulation tools to be developed in a fraction of the time.
Scientists who don't have in-depth knowledge of computer science can now develop an application that they can "plug and play" into the MOOSE simulation platform. In essence, MOOSE solves the mathematical equations embodied by the model. Such a tool means scientists can focus their efforts on the physical science of their field, and MOOSE does the rest. The simplicity has bred a herd of modeling applications describing phenomena in nuclear physics (BISON, MARMOT), geology (FALCON), chemistry (RAT) and engineering (RAVEN, Pronghorn). -
LHC discovers rare particle decay
Physicists have discovered a new particle decay that gives them an indirect way to test models of new physics. Physicists working on experiments at the Large Hadron Collider have observed for the first time the rare decay of a particle made up of two kinds of quarks—anti-bottom quarks and strange quarks—into a pair of particles called muons.
The Standard Model predicts that the particle, called B-sub-s, will decay into two muons very rarely, only three times in every billion decays. However, this prediction assumes that the only particles involved in the decay are the ones physicists already know. If other, unknown particles exist, they might interfere, either making the decay happen more frequently than predicted or reducing the decay rate. Deviations from the predicted rate would firmly establish the presence of new forces or particles. -
Science education-national security link emphasized
Charlie McMillian, director of DOE's Los Alamos National Laboratory, brings a unique perspective to science education.
"In national security science, we can¹t afford to lose a generation of young people in this country," McMillan said. "Particularly U.S. citizens. The world is a changing at an accelerating rate, and we must keep up with those changes if we are to meet the challenges that lie ahead."
McMillan is by law one of four people in the U.S. who must send an annual letter to the President and Congress assessing the state of weapons in the U.S. nuclear stockpile. But because the U.S. stopped full-scale nuclear weapons testing in 1992, the assessments must depend on classified, highly sophisticated computer modeling and non-nuclear experiments.
