Science Friday

At the top of the news this week, of course, the Nobel Prizes in physics, chemistry, and physiology/medicine. The physics prize went to three scientists who comprehensively laid out the theory of "quantum chromodynamics," limning the strong or "color" force that holds quarks together in the atomic nucleus. Two U.S. scientists snagged the physiology/medicine prize for their work on the science of smell -- specifically, their discovery of a family of a thousand genes that engineer a thousand olfactory receptor proteins that, in combination, allow the brain to distinguish 10,000 individual odorant molecules. (Cell, in its 30th Anniversary supplement, posted their original groundbreaking paper, as well a recollection of the work by one of the scientists, Linda Buck.) And in chemistry, the prize went to two Israeli scientists and a U.S. researcher, who together unraveled the mysteries of cellular garbage collection, showing how a molecular "label," the protein ubiquitin, is used inside cells to tag other proteins for breakdown and reuse of their constitutent amino acids. (Interestingly, this is the third straight year that the chemistry prize has recognized biochemical discoveries. Maybe it's time to rename the prize.)

Meanwhile, non-Nobel science marches on. A team of Chinese and American paleontologists, reporting in Nature, have unearthed the oldest known tyrannosaur fossil. The 130 million year old specimen predates those of the best-known tyrannosaur, the celebrated Tyrannosaurus rex, by some 60 to 70 million years -- and is so well preseved that the scientists can discern hairlike "protofeathers" on parts of the jaw and tail. The fossil has been dubbed, rather poetically, Dilong paradoxus -- paradoxical dragon.

New Scientist reports on a company in Mountain View, California, that is developing a new generation of hydrocarbon-membrane fuel cells that, the company hopes, could ultimately allow for economically viable hydrogen cars. Not everyone's convinced of the feasibility of the much touted "hydrogen economy," however; indeed, one British economist is arguing that "converting every vehicle in the United States to hydrogen power would demand so much electricity that the country would need enough wind turbines to cover half of California or 1,000 extra nuclear power stations."

From Science, another demonstration of the potential therapeutic power of embryonic stem cells. Working with a strain of mutant mice that lack working copies of three crucial genes -- and whose offspring, as a result, usually die from major congenital heart defects before birth -- a team of workers from Sloan-Kettering in New York injected the stomachs of female mice with embryonic stem cells before the females conceived any offspring. When the females later conceived, heart defects in their offspring were dramatically reduced, apparently because the stem cells secreted several cardiac-repairing growth factors that circulated through the maternal system to allow "rescue" of the mutant mouse embryos.

A few other tidbits:

--NASA reports that samples from the remains of the Genesis spacecraft -- which was launched in 2001 to sample the solar wind, and which crashed catastrophically to Earth in September when its parachute failed to deploy -- are "looking very, very good."

--A new, nationally representative survey of Americans over fifty suggests that 18 percent of older Americans (one in six) with conditions such as chronic heart disease and depression skip at least some of their prescription medicines because they can't afford the out-of-pocket costs -- and 14 percent do so at least monthly. The study was published in the October 2004 American Journal of Public Health.

--And new research in PLOS Biology uses an unusual line of evidence, the genetic differences between two different species of head lice, to support the notion that the ancestors of modern humans interacted directly -- "through fighting, sharing clothes, or having sex" -- with members of the extinct hominid line Homo erectus.

That's all for now.