Smell is one of the most complex and least-understood senses. Humans have a vast olfactory system that includes close to 400 functional genes, more than are dedicated to any other function. Animals such as dogs and mice have around 1,000 functional olfactory receptor genes.

MIT biological engineers have found a way to mass-produce smell receptors in the laboratory, an advance that paves the way for "artificial noses" to be created and used in a variety of settings. The work could also allow scientists to unlock the mystery of how the sense of smell can recognize a seemingly infinite range of odors.

Artificial noses could one day replace drug- and explosive-sniffing dogs, and could have numerous medical applications, according to Zhang and his colleagues. DARPA recently approved funding for the team's MIT (microfluidic-integrated transduction) RealNose project.

Applications for Templeton-Cambridge Journalism Fellowships In Science And Religion are now open.

The fellowship enables ten print, broadcast or online journalists to pursue an intensive two-month course of study in issues of science and religion. The program includes three weeks of seminars at the university of Cambridge featuring eminent, well-known authorities in the field. Fellows are paid a stipend in addition to travel expenses to Cambridge.

As more and more greenhouse gases are released into the atmosphere and the oceans warm, their chemistry also changes — seawater becomes more acidic as carbon dioxide from the atmosphere dissolves.

According to a paper to be published this week by marine chemists at the Monterey Bay Aquarium Research Institute, these changes in ocean temperature and chemistry will have an unexpected side effect— sounds will travel farther underwater.

Researchers in Italy report that an ancient Chinese herbal remedy known as "horny goat weed" shows potential in lab studies as source for new future drugs to treat erectile dysfunction (ED), an issue commonly treated with drugs like Viagra. The study says they provide scientific evidence supporting the herb's use as a natural aphrodisiac.

In the new study, Mario Dell'Agli and colleagues point out that Viagra (sildenafil) and several other prescription drugs are now available for ED, or male impotence. ED affects an estimated 18 million men in the United States alone. Studies show, however, that these drugs may cause side effects such as headache, facial flushing, stomach upset, and visual disturbances.

In research conducted at the University of Calgary, climate change scientist David Keith and a team of researchers showed it is possible to reduce carbon dioxide (CO2), the main greenhouse gas that contributes to global warming, using a relatively simple machine that can capture the trace amount of CO2 present in the air at any place on the planet.

The research is significant because air capture technology is the only way to capture CO2 emissions from transportation sources such as vehicles and airplanes. These so-called diffuse sources represent more than half of the greenhouse gases emitted on Earth.

Researchers in Pennsylvania report results of laboratory tests and road tests verifying that a simple, inexpensive device attached to a car engine's fuel injector can boost gas mileage by up to 20 percent. That translates into several more miles per gallon, they say, and publish their study in the November 19 issue of Energy & Fuels.

In the study, Rongjia Tao and colleagues describe development and testing of a new fuel economy booster. The small device consists of an electrically charged tube that can be attached to the fuel line of a car's engine near the fuel injector. The device creates an electric field that thins fuel, or reduces its viscosity, so that smaller droplets are injected into the engine. That leads to more efficient and cleaner combustion than a standard fuel injector, the researchers say.