Scientific American Online

The Federal Communication Commission's (FCC) recently released National Broadband Plan has met with mixed reactions from the industries with a stake in the availability of broadcast spectrum. Whereas technology companies producing and serving data to these wireless gadgets want the government to remove a potential bottleneck to the Internet, broadcasters are feeling pinched, having already surrendered the unused "white spaces" in between their channels last year during the digital TV transition. [More]

A New York Times reporter recently wrote this sentence: “Like most--heck, all--of the women I know, my relationship to food, to my weight, to my body is…complicated.” That relationship is now visible in our brains.

When anorexic and bulimic women see images of overweight women, an area of the brain, the medial prefrontal cortex, lights up in a functional MRI. This region is associated with identity and self-reflection.

I remember my excitement one morning in the winter of 2006 when I peered through a microscope in my laboratory and saw a colony of cells that looked just like embryonic stem cells. They were clustered in a little heap, after dividing in a petri dish for almost three weeks. And they were glowing with the same colorful fluorescent markers scientists take as one sign of an embryonic cell’s “pluripotency”--its ability to give rise to any type of tissue in an organism’s body. But the cells I was looking at did not come from any embryo: they were regular adult mouse cells that had seemingly been rejuvenated by the addition of a simple cocktail of genes.

Could it really be so easy to roll back the internal clock of any mammalian cell and return it to an embryonic state? I was not the only one wondering at the time. Shinya Yamanaka of the University of Kyoto and his colleagues had just published a groundbreaking study in August 2006 that revealed their formula for creating what they called induced pluripotent stem cells (iPSCs) from the skin cells of mice. Researchers had been struggling for years to understand and control the enormous potential of embryonic stem cells to produce customized tissues for use in medicine and research--as well as contending with political and ethical controversies over the use of embryos, scientific setbacks and false hopes generated by previous “breakthroughs” that did not pan out. So stem cell scientists were surprised and a little bit skeptical of the Japanese group’s results at first. But that morning in the lab, I could see firsthand the results of following Yamanaka’s recipe.

When you read hundreds of letters from readers every month, as I do, common patterns of argument emerge. I can’t answer every note individually, so in this column I’d like to at least respond to one type of assertion. That is the idea, whenever the letter writer doesn’t agree with an expert-informed point of view expressed in Scientific American , that science should not mention or touch on politically sensitive areas--that science is somehow apart from social concerns. I say: Wrong.

Science findings are not random opinions but the result of a rational, critical process. Science itself advances gradually through a preponderance of evidence toward a fuller understanding about how things work. And what we learn from that process is not just equivalent to statements made by any another political-interest group. It is evidence-based information that is subject to constant questioning and testing from within the scientific community. Thus, the science-informed point of view is a more authoritative and reliable source of guidance than uninformed opinions. We should not discount its value in informing public discourse.

A metal pin adorning a military uniform signifies rank; a ring on the left hand’s fourth finger announces matrimony. [More]

LONDON/OSLO (Reuters) - Iceland's erupting volcano has spewed plenty of ash but far less greenhouse gas than Europe's grounded aircraft would have generated.

Carbon dioxide emissions totaled 150,000 tonnes a day in the early days of the eruption, according to Durham University. That compares with 510,000 tonnes per day emitted when planes are flying as normal over the continent.

By Brendan Borrell

In her 25 years of research, Gail Prins, a reproductive physiologist at the University of Illinois in Chicago, had got used to doing science her way. [More]

John Nagy, author of Invisible Ink: Spycraft of the American Revolution , discusses the codes, ciphers, chemistry and psychology of spying in the American Revolution, in a talk recorded by podcast host Steve Mirsky [ left ] at the historic Fraunces Tavern in New York City. [More]

SAN JOSE, California--Michael Bledsoe's story begins like that of many other Iraqi war veterans. In 2007, he was chasing insurgents through Anbar province when a roadside bomb exploded, breaking Bledsoe's back and both his feet. A former Army Ranger working as a security contractor, Bledsoe soon knew his high-paying military career was over. [More]

The tree species known only as Pennantia baylisiana could be the rarest plant on Earth. In fact, the Guinness Book of World Records once called it that. Just a single tree exists in the wild, on one of the Three Kings Islands off the coast of New Zealand, where it has sat, alone, since 1945. It didn't used to be so solitary, but humans introduced goats to the island, which ate every other member of its species.

Over the last few decades, scientists have tried to create more P. baylisiana trees, but aside from getting cuttings to grow, simple biology got in the way: The tree was thought to be female, and it appeared to need a male to properly generate fruit and seeds.

By Nicola Jones

Results are pouring in from an ambitious project that has wired the floor of the northeast Pacific Ocean with an array of cameras, seismometers, chemical sensors and more. [More]

The largest trial to date of "brain-training" computer games suggests that people who use the software to boost their mental skills are likely to be disappointed.

The study, a collaboration between British researchers and the BBC Lab UK web site, recruited viewers of the BBC science program "Bang Goes the Theory" to practice a series of online tasks for a minimum of ten minutes a day, three times a week, for six weeks. [More]

NASA's shuttle Discovery landed safely Tuesday morning after poor weather had thwarted two initial landing opportunities Monday. The orbiter touched down at Kennedy Space Center in Florida at 9:08 A.M. Eastern Daylight Time, ending its 15-day mission to the International Space Station . [More]

On paper, the main crux of the Federal Communications Commission's (FCC) recently released National Broadband Plan is fairly straightforward: help 100 million rural, underprivileged and otherwise underserved households across the U.S. get access to the Internet at speeds of at least 100 megabits per second over the next decade. The reality of the country's efforts to expand broadband access is much more complicated, according to a roundtable discussion hosted Monday by New York Law School in New York City. [More]

MONTREAL--Rational calculations do not dictate financial decisions, as psychologists have revealed in recent years. Emotions often sway our spendthrift or miserly ways. In particular, positive feelings promote risk taking--gambling in Vegas, say, or going on a shopping spree--whereas bad moods prompt protective selling or saving. In some cases, our feelings may have an obvious origin: studies show that sunshine breeds stock surges, whereas clouds curtail purchasing. But much of what influences our spending is far more subtle--subliminal, in fact. Now psychology graduate student Julie L. Hall of the University of Michigan reports at the Cognitive Neuroscience Society 2010 annual meeting that subconscious emotional cues have a far greater impact on financial risk taking than conscious ones do. What is more, one particular brain region mediates the connection between what influences our feelings and the financial decisions we make. [More]

What happens when a language learned as a child is forgotten over time? Many adoptees and emigrants have no conscious memory of their native tongue, but a new study suggests at least some information remains in the brain. [More]

By Patrick Lannin

REYKJAVIK (Reuters) - The ash cloud surging from an erupting Icelandic volcano is hanging lower in the air, which is good news for travellers, but strong winds higher up moving ash still made conditions uncertain, officials said on Tuesday.

WASHINGTON--To decrease your risk of cancer , don't count on antioxidant supplements, a panel of researchers said here at the annual meeting of the American Association for Cancer Research . But assessing antioxidants' role (and that of many other dietary supplements) in preventing disease has been notoriously difficult. [More]