DiscoverJune 2013的目錄

Crops Wars Wars Andrew Curry discussed the fight over GMOs in Europe in our April cover story, “Seeds of Conflict” (page 38). “Seeds of Conflict” had a measly two sentences addressing monocultures, a massively detrimental impact of GMO crops. There were more sentences giving detailed descriptions of the attire of the author’s interview subjects than the ecological ramifications of morphing the biodiversity that supports life on this planet into corn, soy and wheat fields. Karissa Kneeland Manchester, ME I was sorely disappointed [with “Seeds of Conflict”], especially in the sidebar on anti-GMO efforts in the U.S. A person unfamiliar with data on the subject might find that the anti-GMO arguments are on an equal footing with the use-of-GMO arguments. They are not. The consensus of the scientific community, via peer-reviewed…

The human brain is a swirl of colorful connections in this image produced by a powerful new MRI scanner at Massachusetts General Hospital’s Athinoula A. Martinos Center for Biomedical Imaging. The machine’s images are not only beautiful (one was recently used by rock band Muse as an album cover) but they suggest that the brain is not a tangled mass of neurons, but an organized structure with a simple, geometric pattern — a grid of ribbon-like pathways that cross at straight intersections, like the streets of New York. “We’re seeing stuff that there’s no other way to see, not even under a microscope,” says Van Wedeen, director of connectomics at the Martinos Center. “We’re discovering the structure of the brain for the first time.”…

Rats are among the most studied creatures on the planet, but scientists typically observe them at a distance. Now humans can interact with rodents on equal terms, thanks to a mind-bending experiment conceived by virtual reality pioneers Mel Slater and Mandayam Srinivasan. The experiment, described in a recent paper in the journal PLOS One, consists of two real locations plus one virtual environment: a lab in Barcelona; a 1-foot-wide arena in an animal care facility seven miles away; and a virtual version of that arena online. In the Barcelona lab, a human participant straps on high-definition goggles to see the virtual arena through the eyes of an avatar, or digital double. When he turns, his avatar turns; he can move his double forward and back using a hand-held remote. The…

CONVENTIONAL WISDOM The current system of competitive grants to individual researchers is the best way to finance medical research. CONTRARY VIEW Unorthodox methods emphasizing collaboration can be at least as beneficial as grants. For nearly seven decades, federal agencies and many private funders have financed medical research through competitive grants to individual scientists who submit proposals for particular projects. This system is intended to match available funds with the best researchers and ideas. But today’s competition for limited grant money encourages overly safe research, aimed more at producing positive results to bolster future proposals than at breaking new ground. The current system discourages high-risk, high-payoff science and the publishing of crucial but less grant-worthy negative findings, slowing development of medical treatments. Plus, scientists must spend time writing multiple detailed proposals,…

As temperatures rise around the globe, glaciers are shrinking at an unprecedented rate. The resulting glacial meltwater can form dangerous lakes contained only by unstable rock and debris. These can burst from their basins at any moment, flooding communities and potentially killing thousands. Equipped with mountaineering gear and a Ph.D. in geography, Alton Byers, the director of science and exploration at the nonprofit Mountain Institute in Washington, D.C., has spent his career traversing treacherous high-altitude ridges and navigating alpine wilderness to prepare remote Himalayan villages for climate change. His latest project — the High Mountain Glacial Watershed Program — blends the best of modern technology with on-the-ground observation to mitigate the coming challenges associated with glacial lake outbursts. I am working now on Imja Lake in the Mount Everest area…

In his newest book, Mission to Mars, Buzz Aldrin outlines his vision for exploring the Red Planet. He writes that “Mars has been flown by, orbited, smacked into, radar examined, and rocketed onto, as well as bounced upon, rolled over, shoveled, drilled into, baked and even blasted. Still to come: Mars being stepped on.” DISCOVER staff writer Breanna Draxler spoke with Aldrin about Mars colonization and the moonwalker’s new role as a spokesman for the Axe Apollo fragrance. Why should we go to Mars? I believe it’s sort of a destiny of humanity to move outward and not turn around and come back. What is your motivation for making it a permanent settlement? We may find the Earth uninhabitable for varieties of reasons in the future — some of our…

Green Bank, West Virginia 38d-25"-48.2"N 79d-49’-03.93"W nrao.edu/index.php/learn/gbsc NESTLED IN THE ALLEGHENY MOUNTAINS THAT border Virginia, a 2,700-acre complex of radio telescopes has served as a portal to deep space for more than 50 years. Visitors to the NRAO can see the scopes, stroll the parklike grounds and learn about the pioneers of radio astronomy, but they can’t use a cell phone — 13,000 square miles around the installation are a designated National Radio Quiet Zone to minimize interference with ongoing data collection. WHAT A DISH: The Robert C. Byrd Green Bank Telescope (GBT) is the crown jewel of the observatory complex. The world’s largest fully steerable single-dish antenna, the GBT can access 85 percent of the celestial sphere and, at 485 feet, is taller than the Statue of Liberty. Despite…

SLEEP WAS CONSUMING ANNA Sumner’s life. Her yearning for sleep first emerged in the early 1990s when she was a high school senior. Later, as a Princeton undergraduate, she alarmed her parents by spending large chunks of the holidays at home in bed, asleep. Her flexible schedule, which continued through law school at Duke, allowed her to conceal her prodigious sleep needs from herself and others. Still, she knew something was badly wrong: Regularly forgoing breakfast or a shower to gain a few extra minutes of shut-eye and sleeping away a friend’s wedding after traveling cross country for the event just weren’t normal behaviors. The demands of the workforce finally forced a reckoning. By the time Anna sought me out at Emory University’s Sleep Center in 2005, she was devoting…

October used to be a good month for sharks in La Paz. When the waters cooled, hammerhead sharks arrived in this part of the Mexican state of Baja California in droves. In the late ’70s, marine biologists discovered massive swirling schools of hammerheads around a nearby undersea mountain called El Bajo — so many that they could simply hold their breath, dive down a few dozen feet, pick one at random, and affix an electronic tag on it with a stick. At the time, perhaps because of their odd-shaped head, the iconic sharks were feared as maneaters. The seamount eventually became a magnet for scientists and photographers alike. The images of hundreds of schooling hammerheads, with their instantly recognizable oblong heads, became an emblem of the ocean’s bounty and one…

A circuit board containing Modha’s golden neural chip is shown at right. Within the square of gold is a smaller, golden rectangle the size of a grain of rice. The rectangle is the core that houses the electronic equivalent of biological nerve cells, or neurons. In living neurons, electrochemical signals travel down a long, slender stalk, called an axon, to protrusions called dendrites. The signals leap from the axons across a synapse, or gap, to the dendrites of the next nerve cell in the neural net. The process is emulated in Modha’s silicon chip, where 256 processors in the core each serve as an artificial neuron that receives signals from its own “dendrite line.” (See magnified grid, far right.) Those lines are arranged parallel to one another but perpendicular to…

To bring movement back to Rob Summers’ paralyzed lower body, scientists and doctors surgically implanted a package of 16 small electrodes, just a few centimeters long, above the protective membrane layers of his spinal cord. Wires lead from the electrodes to a small rectangular neurostimulator device inserted in Summers’ lower back. Summers uses a remote control to send an electrical current from the neurostimulator to the array and a group of neurons — called interneurons — in the spinal cord. Interneurons in the lower spine send tailored messages to specific muscles via another type of neuron called motor neurons. Excited into action by the electrical charge, neurons communicate with each other and with muscles to create movement. The electrode array and its remote control essentially replace the brain, which would…

ONE OF THE MOST SHOCKING THINGS ABOUT A DARK COUNTRY SKY IS HOW disorienting it is: The brain has a difficult time finding recognizable patterns in the multitude of stars. Urban skies are much easier to read, reduced to their brightest, most distinctive elements. Fifteen minutes is all you need to learn your way around the city stars of summer. The key is a grouping of three stars now rising in the eastern sky, opposite the setting sun. The highest and brightest is Vega. To the left is Deneb, surrounded by dimmer stars that form a large, loose cross. To the right is Altair, tightly flanked by two fainter stars. Collectively, the three form a pattern called the Summer Triangle. Each night through the summer months they rise a little…

WHENEVER JUNE ROLLS AROUND, I THINK OF MY DAD. No, not because of Father’s Day (a greeting-card holiday he had no use for) but because his birthday was in June, and this year he would have been 70. For some reason, that was a talismanic number for him. “By the time I’m 70 ...” was a common preface to his many suppertime pronouncements about the future. As in, “By the time I’m 70, they’ll have the cure for cancer.” Or “... gas-powered cars will be obsolete.” Or “... we’ll have colonies on the moon and even Mars.” He reveled in predicting scientific and technological breakthroughs and encouraged me to come up with my own, although as a kid all I wanted from the future was a two-way wrist TV just…

WHY DO WE LIE TO OURSELVES? That’s what evolutionary biologist Robert Trivers has spent 30 years trying to figure out. “Our sensory systems are organized to give us a detailed and accurate view of reality,” he says, “but once this information arrives in our brains, it is often distorted and biased to our conscious minds.” We repress painful memories, create false ones, rationalize immoral behavior and jack up our self-esteem. We deny ourselves the truth. Trivers, a professor of anthropology and biological sciences at Rutgers University in New Jersey, is not as well-known to the public as, say, Harvard’s Steven Pinker or E.O. Wilson. Evolutionary biologists, however, put him in a class by himself. Pinker has called him “one of the great thinkers in the history of Western thought.” In…

Nanoengineers have a shiny, new tool at their disposal: laser-producing devices the size of viruses. The Lilliputian contraptions consist of two gold triangles whose peaks are pointed toward each other, creating a sort of three-dimensional bow tie shape. This particular geometry forms a “hot spot” between the metallic triangle points capable of concentrating electromagnetic fields in a small volume — just tens of nanometers across. “Shape is really important,” says chemist and materials scientist Teri Odom of Northwestern University, the corresponding author of the findings. Typically, lasers require a much larger cavity that allows light to bounce back and forth between mirrors for it to become amplified into a laser (light amplification by stimulated emission of radiation). “That’s what’s spectacular about the structure of these materials — you can get…

Czech biologist Vlastimil Hart wanted to know if common carp can detect magnetic fields, but he just couldn’t figure out how. Then it occurred to him to follow his dream, literally — one he’d had that included big tubs of carp. He and his colleagues photographed 14,537 carp for sale at local holiday markets and calculated compass bearings from the photos. They discovered that the fish had a marked preference for aligning themselves in a north-south orientation. Although other animals — most notably birds — are known to be magnetoreceptive, there has been little documentation of the phenomenon in non-migratory fish. Team member Hynek Burda speculates that the trait might help carp flee danger. “Frightened animals do not have time to unite on one common direction of escape, so they…

NORTH AMERICA Discovery Channel, 9 p.m. EDT May 19 Grizzly bears become aquatic ballerinas as they dive deep into Alaskan waters for salmon. Thousands of miles to the south, the rare desert jaguar moves ghostlike through a Mexican landscape. And across the breadth of the continent, massive severe weather systems gather strength, their destructive power captured in HDR time-lapse sequences. The production crew for the Discovery Channel’s North America series spent more than three years filming the show, shivering in Canada’s frozen Yukon territory and sweltering in the rainforests of Belize. All you have to do is sit back, watch and be awed. Discovery.com/Northamerica…

Before he joined the crew of the U.S.S. Enterprise as the beloved chief engineer Montgomery Scott in 2009’s Star Trek and its sequel, Star Trek Into Darkness (in theaters May 17), actor and writer Simon Pegg earned a devoted fan base with such quirky hits as Shaun of the Dead and the British series Spaced. A lifelong sci-fi and science fan, his comments about the joys of being a geek have been embraced, reposted and retweeted into perpetual online orbit. Pegg phoned DISCOVER Associate Editor Gemma Tarlach from his home in London to talk about his iconic status. A popular meme circulating online attributes to you the quote “Being a geek is all about being honest about what you enjoy... Being a geek is extremely liberating.” Were you surprised those…

6-16 Seattle Science Festival How do salt and temperature work together to create ice cream? How do bees help the Earth? Find out at citywide events for all ages. seattlesciencefestival.org 5-8 Smartie Showdown National finalists for Toshiba/NSTA’s ExploraVision, the world’s largest K-12 student science and technology competition, show off their projects in Washington, D.C. exploravision.org 5 Reduce Your Foodprint “Think.Eat.Save.” This year’s World Environment Day theme addresses a sobering fact: One-third of all food produced globally is wasted. unep.org/wed 1 Batten Down the Hatches! Atlantic hurricane season officially kicks in today. Do you have your disaster supply kit and evacuation plan ready? nhc.noaa.gov 7 Rediscover a Lost World Will Smith and son Jaden explore a posthuman planet in After Earth. M. Night Shyamalan directs the big-budget sci-fi flick. afterearth.com 8…

Robert Bea has an unusual specialty: He studies disasters. As one of the world’s leading experts in catastrophic risk management, the former Shell Oil Co. executive sifts through the wreckage to unravel the chain of events that triggers accidents. The blunt-spoken civil engineer has spent more than a half-century investigating high-profile engineering failures, from the space shuttle Columbia’s horrific end to the explosion of the Deepwater Horizon oil-drilling rig in the Gulf. A professor emeritus of civil engineering at the University of California, Berkeley, Bea’s disaster autopsy methods — such as looking at the organizational breakdowns that lead to calamities — have been widely adopted. Although policymakers and corporate honchos seek his counsel, sometimes they don’t like what he has to say — witness the flak he took from BP…

Cities are not static objects to be feared or admired, but are instead a living process that residents are changing all the time. Given how much bigger and more common cities are likely to become over the next century, we’ll need to change them even further. Using predictive models from engineering and public health, designers will plan safer, healthier cities that could allow us to survive natural disasters, pandemics and even a radiation calamity that drives us underground. But there is an even more radical way we’ll transform our cities. Over the next two centuries, we’ll probably convert urban spaces into biological organisms. By doing this, we will make ourselves ready to prevent two of the biggest threats to human existence: starvation and environmental destruction. Eventually this biological transformation might…

To gain more insight into neural computing, Modha has mapped the brain of the rhesus macaque monkey, which is similar to our own. He later used the map to simulate a human-scale brain on an IBM supercomputer. The macaque-derived map at left models the core — the prefrontal cortex and other parts of the brain involved in consciousness, cognition and higher thought. Communication throughout the network is mainly conducted through the core, where 88 percent of all connections start or end. In a computer, such connectivity could be implemented through a network of golden chips spanning the entire system. What Modha finds most interesting is that the macaque’s innermost core appears to include two brain networks found in humans — one that activates introspective thought and another that activates goal-oriented…

Electrical stimulation is one way to get paralyzed patients back on their feet, but researchers are also testing a number of other novel methods in hopes of finding a pure biological cure — one that transcends invasive intervention or constant mechanical support. The strategies below are preliminary but promising. Preventing damage After a spinal cord injury, nearby neurons lose insulation and the ability to communicate via natural electrical impulses. When scientists gave mice an oral drug called LM11A-31 (designed to prevent neural degeneration in Alzheimer’s patients) just hours after a complete spinal cord injury, it limited the death of cells that protect nerve fibers, allowing test rodents to retain their ability to walk and swim. The drug binds with proteins that normally kill off the protective cells after an injury;…

1. The oldest known recipe is for a 4,000-year-old beer made by the Sumerians. 2. In the 1980s, Anchor Brewing re-created these ancient Fertile Crescent suds. 3. Sumeria’s neighbors, the Egyptians, built the pyramids under the influence. Workers at Giza received about four liters of beer a day, according to Patrick McGovern, a biomolecular archaeologist at the University of Pennsylvania. 4. Beer (in part because it contains antimicrobial ethanol) was a healthier drink than polluted Nile river water. 5. Ethanol, the intoxicant in beer, is a powerful antiseptic, but not a good cold remedy. The optimal blood alcohol content to kill germs would be more than 60 percent. Alas, that’d kill you, too. (Fatal alcohol poisoning occurs between 0.40 and 0.50 percent.) 6. Salud! Researchers at the University of Western…

This full-scale model of the James Webb Space Telescope was on display in Austin, Texas, during the South by Southwest Conferences and Festivals in March. The real telescope, now under construction at the Goddard Space Flight Center in Maryland, will be Hubble’s successor and is scheduled to launch later this decade. With a mirror 21.3 feet in diameter (more than 2.5 times the size of Hubble’s) composed of 18 hexagonal segments, Webb will be the largest telescope in space. It will reside much farther away than Hubble, too (about 932,000 miles from Earth) and will be “parked” in a gravitationally stable area constantly opposite the sun. Because Webb will be away from the shade of near-Earth orbit, it’s been designed with a multilayered sunshade the size of a tennis court…

At the level of tiny particles, the laws of physics are symmetrical in time. A reaction that proceeds in one direction (such as particle A transforming into particle B) is just as likely to occur in the reverse direction (particle B transforming into A). It’s not too strange a concept: A video showing a billiard ball’s initial bounce off a pool table’s cushion would look the same whether it was running backward or forward in time. The physics works just as well, and identically, either way. Yet experiments since the 1960s have suggested there should be exceptions to this rule — special cases of so-called “time-reversal violation.” The first conclusive evidence of such a violation was finally discovered late last year by collaborators on an experiment named BaBar at Stanford…

Criminals should start investing their ill-gotten gains in a new pair of kicks. That’s because computer scientists have just gotten a lot better at linking the prints of well-worn shoes back to their owners. With each step you take, you not only leave an impression on your surroundings, but you also affect the sole of the shoe itself. This can be just the wearing of the tread caused by your weight and walking gait, or it can be something as distinctive as a slash or puncture. However, most footwear forensics is still done manually, unlike fingerprints, and with thousands of tread patterns on the market, that’s an eye-straining job. Basically, an investigator sits in a dark room wading through thousands of images of soles, hunting for similarities between, say, the…

On the outside, it looks like every other brain scanner — a hollow metal cylinder with a hard, retractable cot. On the inside, however, the Connectome scanner boasts the most advanced brain imaging technology in the world. Installed at Massachusetts General Hospital in Boston in September 2011, this magnetic resonance imaging (MRI) scanner is poised to be the Hubble Space Telescope of neuroscience. The scanner, built as part of an $8.5 million federal grant, features a gradient field that is eight times more powerful than a conventional MRI machine. It produces images that are four to eight times more detailed, and does so in one-sixth of the time. The scanner, quiet enough for a baby to sleep inside, relies on a new brain-imaging technique called diffusion MRI, which maps long-distance…

BRILLIANT BLUNDERS by Mario Livio Everyone makes mistakes, even supergeniuses. Our greatest minds’ biggest errors often reveal insights into their personalities and fields of study, from Darwin’s incomplete understanding of his theory of evolution to Einstein’s rejection of the cosmological constant, a concept that foreshadowed the discovery of dark energy. Overeager to provide context, astrophysicist and author Livio pads the book with too much history and basic science irrelevant to the topics at hand. But he has an engaging style that entertains even as it revisits much of high-school science class. BILL ANDREWS WILD ONES by Jon Mooallem Dismayed by the disconnect between reality and the cartoonish animals populating his young daughter’s pajamas, books and view of the natural world, journalist Mooallem sets off to explore often circuitous human-animal relationships:…

Our feline friends’ ear movements can tell us a lot with a twitch or two. Wouldn’t it be great if that were true for humans, too? NeuroSky’s Necomimi cat ears are the latest consumer gadget to use electroencephalography (EEG), in this case to reveal a wearer’s degrees of relaxation and focus. Unlike old-school mood rings that change color based on body temperature, the ears reportedly react to the wearer’s brain waves. No word if extended wear causes unnatural interest in balls of yarn. See the ears in action at DiscoverMagazine.com/Cat-ears…

WE THINK BIG. WE THINK OUT loud. We think outside the box. We think on our feet. But what we don’t do is think entirely inside our heads. Thoughts aren’t confined to our brains — they course through a network that expands to our bodies, perhaps eliminating, at times, the need for complex thought. The notion that we think with the body — the startling conclusion of a field called embodied cognition — flies in the face of long-standing views. Early cognitive psychologists defined thought as an activity that resides in the brain: Sensory data come in from eyes and ears, fingers and funny bone, and the mind turns these signals into disembodied representations that it manipulates in what we call thinking. Sure, the body may collect sensory information, like…

Deepwater Horizon, 2010 The Deepwater Horizon oil-drilling rig exploded in the Gulf of Mexico, killing 11 crewmen and igniting a fire that could not be extinguished. Two days later the rig sank, leaving the well gushing in the seabed. It ultimately leaked 210 million gallons of oil in the largest offshore spill in U.S. history. » What was ignored? BP, the industry and federal regulators understood the potential for an uncontrolled blowout in Deepwater drilling, but they failed to heed warnings about the structural weaknesses in the cement casings that protect the well pipes. Plus, the blowout preventer hadn’t been working properly for several days. » What would have improved the outcome? Delivering the required degree of safety consistently and ensuring that protocols were followed. Understanding that wells pumping 162,000…

The day he got the news that would transform his life, Dharmendra Modha, 17, was supervising a team of laborers scraping paint off iron chairs at a local Mumbai hospital. He felt happy to have the position, which promised steady pay and security — the most a poor teen from Mumbai could realistically aspire to in 1986. Modha’s mother sent word to the job site shortly after lunch: The results from the statewide university entrance exams had come in. There appeared to be some sort of mistake, because a perplexing telegram had arrived at the house. Modha’s scores hadn’t just placed him atop the city, the most densely inhabited in India — he was No. 1 in math, physics and chemistry for the entire province of Maharashtra, population 100 million.…

ROB SUMMERS IS STANDING UP. Two feet on the ground, legs straight, hips squared. He has done it thousands of times before — out of bed in the morning to practice with his championship-winning collegiate baseball team, or up from the couch to get a snack. Most memorably, he stood up on a July night in 2006 to walk out the door and over to his parked car on a street in Portland, Ore. Standing next to his Ford Explorer, he saw the lights of another vehicle approaching from behind. It was coming fast — too fast. Before he could get out of the way, the car threw him to the ground, and the driver fled what was a gruesome scene: Summers lay on the asphalt in a pool of…

SUPER-TIGER IS LOST SOMEWHERE on the snow dunes of Antarctica. Strictly speaking, “lost” isn’t quite right. More like “inaccessible.” Walter Robert Binns knows the exact whereabouts of his wayward, two-ton cosmic-ray experiment: 82 degrees 14 minutes 69 seconds south, and 81 degrees 54 minutes 88 seconds west. That’s about 1,000 miles east from McMurdo Station. But the sun has set on Super-TIGER, and it will not rise again until September. Temperatures are headed down to minus 70 degrees Fahrenheit. No sane search party would head out in the polar darkness, so for now there is nothing to do but wait. That idleness contrasts starkly with the flurry of activity that came just before. For nearly two months, Super-TIGER took a wild ride 24 miles above the South Pole, hanging beneath…