Tuesday, October 28, 2008

Training the Brain: Scientific American (archiving magazine articles 07/2005)

Training the Brain: Scientific American

To medicate or not? Millions of parents must decide when their child is diagnosed with attention-deficit hyperactivity disorder (ADHD)--a decision made tougher by controversy. Studies increasingly show that while medication may calm a child's behavior, it does not improve grades, peer relationships or defiant behavior over the long term.

Consequently, researchers have focused attention on the disorder's neurobiology. Recent studies support the notion that many children with ADHD have cognitive deficits, specifically in working memory--the ability to hold in mind information that guides behavior. The cognitive problem manifests behaviorally as inattention and contributes to poor academic performance. Such research not only questions the value of medicating ADHD children, it also is redefining the disorder and leading to more meaningful treatment that includes cognitive training.

"This is really a shift in our understanding of this disorder from behavioral to biological," states Rosemary Tannock, professor of psychiatry at the University of Toronto. Tannock has shown that although stimulant medication improves working memory, the effect is small, she says, "suggesting that medication isn't going to be sufficient." So she and others, such as Susan Gathercole of the University of Durham in England, now work with schools to introduce teaching methods that train working memory. In fact, working-memory deficits may underlie several disabilities, not just ADHD, highlighting the heterogeneity of the disorder.

Ask an Astrophysicist

Ask an Astrophysicist

Thursday, October 16, 2008

The Microwave Magician (archiving magazine articles 12/2007)

PopSci's Best of What's New 2007: "I’m not sure if I’m watching a magic trick, or an invention that will make the cigar-chomping 64-year-old next to me the richest man on the planet. Everything that goes into Frank Pringle’s recycling machine—a piece of tire, a rock, a plastic cup—turns to oil and natural gas seconds later. “I’ve been told the oil companies might try to assassinate me,” Pringle says without sarcasm.

The machine is a microwave emitter that extracts the petroleum and gas hidden inside everyday objects—or at least anything made with hydrocarbons, which, it turns out, is most of what’s around you. Every hour, the first commercial version will turn 10 tons of auto waste—tires, plastic, vinyl—into enough natural gas to produce 17 million BTUs of energy (it will use 956,000 of those BTUs to keep itself running).

Pringle created the machine about 10 years ago after he drove by a massive tire fire and thought about the energy being released. He went home and threw bits of a tire in a microwave emitter he’d been working with for another project. It turned to what looked like ash, but a few hours later, he returned and found a black puddle on the floor of the unheated workshop. Somehow, he’d struck oil.

Or rather, he had extracted it. Petroleum is composed of string"

new solar (archiving magazine articles 12/2007)

PopSci's Best of What's New 2007: "Imagine a solar panel without the panel. Just a coating, thin as a layer of paint, that takes light and converts it to electricity. From there, you can picture roof shingles with solar cells built inside and window coatings that seem to suck power from the air. Consider solar-powered buildings stretching not just across sunny Southern California, but through China and India and Kenya as well, because even in those countries, going solar will be cheaper than burning coal. That’s the promise of thin-film solar cells: solar power that’s ubiquitous because it’s cheap. The basic technology has been around for decades, but this year, Silicon Valley–based Nanosolar created the manufacturing technology that could make that promise a reality.

The company produces its PowerSheet solar cells with printing-press-style machines that set down a layer of solar-absorbing nano-ink onto metal sheets as thin as aluminum foil, so the panels can be made for about a tenth of what current panels cost and at a rate of several hundred feet per minute. With backing from Google’s founders and $20 million from the U.S. Department of Energy, Nanosolar’s first commercial cells rolled off the presses this year.

Cost has always been one of solar’s biggest problems. Traditional solar cells require silicon, and silicon is an expensive commodi"

offsetting your carbon (archiving magazine articles 7/2005)

Wired 13.07: START

Now they have TerraPass, a clever eco-capitalism experiment. Launched by a group of Wharton Business School classmates, the startup sells a decal that drivers can slap on their windshields. The sticker price - $79.95 for SUVs, less for greener cars - gets invested in renewable energy projects and credits. The credits are traded through local brokers on the new Chicago Climate Exchange.

TerraPass lets consumers participate in an emissions trading system the US established in 1990. (Give credit to economist Ronald Coase, who won a Nobel Prize for the idea in 1991.) Under the system, industrial operations that spew less than their share of emissions can sell a credit to companies that fail to keep gunk out of the air. In effect, the dirtier factories can pay greener operations to do the work of cutting emissions. The approach has taken off worldwide, spawning a billion-dollar market.

And it's not just for big-time polluters. Today, farmers cash in on credits by collecting and processing cow dung, which produces globe-cooking methane. Land-owners earn credits by installing wind farms on their blustery fields, which top off the power grid with carbon-free electricity.

But until now, the Chicago Climate Exchange was off-limits to all but registered traders, and the transaction cost of buying credits piecemeal from small outfits was too high. TerraPass aggregates the money plunked down by guilty - ahem, environmentally concerned - SUV drivers, allowing them to participate in the market.

YouTube Does Science, From Fruit-Fly Fight Clubs to Stem Cell Extractions (archiving magazine articles 7/2007)

YouTube Does Science, From Fruit-Fly Fight Clubs to Stem Cell Extractions

WIRED MAGAZINE: ISSUE 15.07

YouTube Does Science, From Fruit-Fly Fight Clubs to Stem Cell Extractions

John Geirland Email 06.26.07

Years behind the lab bench taught Moshe Pritsker that the trickiest part of any science experiment isn't the hypothesis, it's the method. The former Harvard researcher learned this lesson back in his student days, after carefully following the instructions on a specialized kit for isolating DNA. "Surprise," Pritsker says, "no DNA!" A colleague finally showed him how to make the kit work. And that gave Pritsker an idea: methodology porn. The Web site he cofounded, the Journal of Visualized Experiments, launched last October. Now its videos of experimental procedures and techniques — from stem-cell culture prep to hippocampal dye injection — get 300 pageviews a day. The journal's still a work in progress (nothing's gone viral yet), but just wait. "No one has published results in video before," Pritsker says. "Scientists don't know how to do it." Here are a few of the journal's faves.

Must-See Experiments

Culture of Mouse Neural Stem Cell Precursors
D. Spencer Currle, Jia Sheng Hu, Aaron Kolski-Andreaco, Edwin S. Monuki, UC Irvine.
Video Extracting a mouse uterus, removing embryos, and harvesting stem cells from the cerebral cortex.
Goal Improving stem-cell handling skills for eventual use on human cells.
Highlight Close shot demonstrating how to use bent forceps to tease out cortical tissue.



Studying Aggression in Drosophila
Sarah Certel, Edward A. Kravitz, Sibu Mundiyanapurath, Harvard Medical School.
Video Building glass arenas and staging bouts between drosophila.
Goal Figuring out how aggression is wired in the brain.
Highlight It's fruit-fly fight club — close-up lunges, blocks, and feints.



Testing Visual Sensitivity to the Speed and Direction of Motion in Lizards
Kevin L. Woo, Centre for the Integrative Study of Animal Behaviour, Macquarie University, Sydney
Video Coaxing Jacky dragons (an Australian lizard species) to take cues from moving dots.
Goal Working with lizards as a model for motion sensing.
Highlight The lizard actually completes the experiment. It's tough to motivate reptiles to stay interested in scientific work, Woo says.

A MILLION LITTLE ID TAGS - Popular Science Magazine, February 2007 (archiving magazine articles)

A MILLION LITTLE ID TAGS - Popular Science Magazine, February 2007:

"Unmistakable identification keeps car thieves away from your ride.

THE THREAT: More than one million vehicles are stolen in the U.S. every year, with a total value of over $7.6 billion. And once thieves remove license plates and vehicle identification numbers, there's no way of knowing who the vehicles once belonged to.

THE SOLUTION: Datadot Technology - a startup company in Australia which has the highest rate of vehicle theft in the developed world—has devised a way to cover valuable items in identifiers as small and invisibly scattered as hairspray droplets on a bouffant. Transparent DataDots are laser-etched with an identification number unique to you and glued to every internal surface of your car, boat or laptop, The sheer number of sand-grain-size dots on treated possessions—up to 5,000—makes it all but impossible for thieves to take them off and sell the harvested parts. In contrast, existing theft-deterrent systems such as a LaJack can be hidden in only one of about 20 places, and so can be removed much more easily.

Cops determine who stolen property belongs to by using a 50x magnifier to read the dots. If a person reporting a theft mentions that the item was Data-Dotted, police departments can access a company-run international database to find out if the car has turned up elsewhere. '"

Blood Simple | Popular Science (archiving magazine articles 7/2007)

Blood Simple | Popular Science

Their solution is a device that converts all blood into type O, the most coveted of the four major blood types because it can be safely transfused into nearly any patient. "Press 'start,' and the machine does everything else," says Douglas Clibourn, the CEO of ZymeQuest.

Surfing the Stars | Popular Science (archiving magazine articles 6/2007)

Surfing the Stars | Popular Science

Within a decade, a dream team of astronomers and computer geeks vows to bring a world-class observatory to every desktop, giving anyone with a PC access to remote galaxies and exploding supernovae. The pledge is the result of a partnership announced last winter between a network of 19 national research institutions and engineers from the search-engine giant Google. Their collective objective is to develop potent software to process the estimated 30 terabytes of astronomy imagery (think 12 billion five-megapixel photos) that will stream nightly from the newly built Large Synoptic Survey Telescope, or LSST, slated to go online in 2013.

Set atop Cerro Pachn Mountain in Chile, the LSST will be the largest survey scope of its kind, sequentially imaging nearly 20 billion astronomical objects in the night sky twice a week at least 2,000 times over the scope's 10-year lifetime. Google's role in this $350-million project (beyond the modest $25,000 annual dues payment) is still largely undefined, but Rob Pike, Google's principal engineer for the LSST, envisions a tool set akin to Google Earth, which combines a search tool with satellite imagery. So instead of killing time flying over your ideal vacation spot onscreen, you can opt for more productive surfing, such as scanning the skies for hazardous near-Earth asteroids.


HOW IT WORKS

One thousand times as powerful as previous telescopes, the LSST will survey the entire sky every three nights using a wide-angle mirror and a three-billion-pixel digital camera. As the telescope rotates on its base, the camera's 15-second exposures take in an area 50 times as large as the full moon. Software will compile three-dimensional imagery to produce time-lapse digital "movies" of the universe.

Tumor Grenades | Popular Science (archiving magazine articles 6/2007)

Tumor Grenades | Popular Science:

"Particle accelerators, the giant machines that create highly energetic beams of subatomic particles, are designed to solve the universe's grand mysteries. Now they're battling cancer. Since 1992, more than 50,000 patients have undergone proton therapy, which uses particle accelerators to precisely blast tumors with high-speed protons.

Now physicists at CERN, the European particle-physics center in Switzerland, have begun experimenting with antimatter made of rare, negatively charged twins of protons, and the results are promising. In studies involving hamster tissue, antimatter therapy has even proved to be four times as powerful as protons.

X-rays, which deliver conventional radiation therapy, burn through the body, increasing the cancer risk in healthy tissue. Protons and antimatter, by comparison, can be tuned to release most of their energy right at the tumor site, thus damaging fewer of the surrounding cells. 'I didn't experience any nausea or radiation burn,' says Florida state congressman Stan Jordan, who received proton therapy for advanced prostate cancer earlier this year at the University of Florida Proton Therapy Institute in Jacksonville. Jordan, who likened the treatment chamber to the Starship Enterprise, says the actual 'beam-me-up-Scotty' part of the therapy lasted less than two minutes.

Unfortunately, each facility costs more than $100 milli"