Scientific American Online

By Jeff Tollefson

The state of California is about to become a giant playground for more than 200 atmospheric scientists. [More]

An experiment looking for the signal of dark matter deep in an underground lab in Italy turned up no candidate signals in 11 days of early operation, the experimental collaboration reported in a paper posted online Monday . The underground detector, called XENON100, only recently began taking data but is already challenging prior claims and hints of dark matter signals, according to the team, which published its findings on the physics preprint repository arXiv.org . [More]

By Matthew Bigg

VENICE, Louisiana (Reuters) - Workers toiled above and below the surface of the Gulf of Mexico on Wednesday to plug a gushing oil leak and protect the U.S. shoreline in one of the biggest spill containment efforts ever mounted.

Dear EarthTalk: Are there any health hazards associated with the use of the new silicone bake ware and cooking utensils?  I have found information associated with the hazards/benefits of Teflon and other cookware but nothing on the use of silicone. --Jean McCarthy, Sebastian, Fla.

For hobbyists like Colette Theriault, a photographer who lives in Ontario, orchids are an addiction. Theriault bought her first Phalaenopsis in 1999 and nurtured it for three years before it bloomed its first pink flowers. The success led to more, until she had 25 orchids crowding her windowsills. In March she discovered yellow spots on the leaves of her collection--a telltale sign of a virus, like those plaguing the orchid industry.   [More]

Climate change has made nights warmer in India over the past decade, an ominous sign for the nation's vital rice crop.

This development could have a far-reaching impact on the yield of rice, causing a shortfall in an important staple crop in a crowded country already grappling with food security and inflationary issues, said Krishna Kumar Kanikicharla, a scientist at the Indian Institute of Tropical Meteorology in Pune, India.

When accidents happen, doctors typically rely on sutures, staples or adhesives to fix the damage. These approaches work, of course, but they tend to cause inflammation in the surrounding tissue and leave scars long after a wound has healed. Researchers at Harvard Medical School and the Massachusetts General Hospital Wellman Center for Photomedicine have recently completed a study they hope will shine some light on this problem--laser light, that is. [More]

Dolphin species on four continents are in danger, warn various reports. [More]

Dear EarthTalk: Isn’t the interest in electric cars and plug-in hybrids going to spur increased reliance on coal as a power source? And is that really any better than gasoline/oil in terms of environmental impact? --Graham Rankin, via e-mail

The chemicals BP is now relying on to break up the steady flow of leaking oil from deep below the Gulf of Mexico could create a new set of environmental problems.

Even if the materials, called dispersants, are effective, BP has already bought up more than a third of the world’s supply. If the leak from 5,000 feet beneath the surface continues for weeks, or months, that stockpile could run out.

BP, the global oil giant responsible for the fast-spreading spill in the Gulf of Mexico that will soon make landfall, is no stranger to major accidents.

In fact, the company has found itself at the center of several of the nation's worst oil and gas–related disasters in the last five years.

Worldwide, women suffer higher rates of eating disorders and obesity than men do--and a recent study may help explain why. [More]

America is an absurdly backward country when it comes to passenger trains. As anyone who has visited Europe, Japan or Shanghai knows, trains that travel at nearly 200 miles per hour have become integral to the economies of many countries. With its celebrated Tokaido Shinkansen bullet trains, Central Japan Railway has for the past five decades carried billions of passengers between Tokyo and Osaka in half the time it would take to fly. A new Madrid-to-Barcelona express train runs at an average speed of 150 miles per hour; since its inception two years ago, airline traffic between the two cities has dropped by 40 percent. In contrast, Amtrak’s showcase Acela train connecting Boston to Washington, D.C., averages just 70 mph. That figure is so low because many sections of the Acela’s tracks cannot safely support high speeds, even though the train itself is capable of sprints above 150 mph. Think of it as a Ferrari sputtering down a rutted country lane.

There has been a recent push to change all this. Earlier this year the Department of Transportation announced the recipients of $8 billion in stimulus funding designed to spread high-speed rail across the U.S. The 2010 federal budget requests an additional $1 billion in rail construction funds in each of the next five years. And in 2008 California voters approved a $9-billion bond measure to initiate an ambitious high-speed rail network that would connect Los Angeles to San Francisco and, eventually, Sacramento and San Diego.

History is not often thought of as a science, but it can be if it uses the “comparative method.” Jared Diamond, professor of geography at the University of California, Los Angeles, and James A. Robinson, professor of government at Harvard University, employ the method effectively in the new book they have co-edited, Natural Experiments of History (Harvard University Press, 2010). In a timely study comparing Haiti with the Dominican Republic, for example, Diamond demonstrates that although both countries inhabit the same island, Hispaniola, because of geopolitical differences one ended up dirt poor while the other flourished.

Christopher Columbus’s brother Bartolomeo colonized Hispaniola in 1496 for Spain, establishing the capital at Santo Domingo on the eastern side of the island. Two centuries later, during tensions between France and Spain, the Treaty of Ryswick in 1697 granted France dominion over the western half of the island. Because France was richer than Spain at this time and slavery was an integral part of its economy, it turned western Hispaniola into a center of slave trade with staggering differences in population: about 500,000 slaves in the western side of the island as compared with only 15,000 to 30,000 slaves in the eastern side.

By Janelle Weaver

The indifference of some mosquitoes to a common insect repellent is due to an easily inherited genetic trait that can be rapidly evolved by later generations, a new study suggests.

By selective breeding, James Logan and colleagues at Rothamsted Research in Harpenden, UK, created strains of Aedes aegyptimosquitoes in which half of the females do not respond to DEET (N,N-diethyl-meta-toluamide) -- a powerful insect repellent. [More]

The immune system's cells work hard to fight off infections. But new research is uncovering their important role in cognition, and a study published online May 3 in The Journal of Experimental Medicine reveals how the immune system's T cells , which aren't present in the brain, can impact learning and memory. [More]