Wireless networking technology will one day deliver high-definition video content and other large data files via the airwaves far faster than that information can be now be delivered over wired systems. But it will take major advances in the electronics that drive computer and radio-frequency systems to create such a high-powered wireless highway.

One of the most basic examples of such a system is a laptop computer equipped with a radio for wireless connectivity. The computer’s performance has generally been improved through upgrades in digital semiconductor performance: shrinking the size of the semiconductor’s transistors to ramp up transaction speed, packing more of them onto the chip to increase processing power, and even substituting silicon with compounds such as gallium arsenide or indium phosphide, which allow electrons to move at a higher velocity.

The key to squeezing higher performance out of the radio side of the equation, according to one company, is using metal-insulator components. "We are potentially at another stepping point, where instead of solid-state semiconductor electronics, we will have metal-insulator electronics," says Garret Moddel, chief technology officer and chairman of Phiar Corporation in Boulder, Colo.

Moddel has good reason to believe this, given that his company builds diodes, radio-frequency (RF) detectors and RF receivers using metal-insulator technology.

Although Phiar’s technology will not be commercially available until next year, the company’s approach is expected to enhance the performance and cut the costs of wireless networks by introducing a simpler, less expensive manufacturing process. The company does this by using stacks of metals and insulators at nanoscale thicknesses—tens of angstroms, a unit of length equal to one ten-billionth of a meter; the space between atoms is generally two or three angstroms—to create high-frequency, up to three terahertz. (A terahertz is a trillion hertz, a thousand times speedier than a gigahertz-level processor, but slower than an optical network.)

"We’re bridging the performance between photonics and electronics," says Adam Rentschler, Phiar’s director of business development.

Conventional semiconductors are built using silicon-based substrates (the material upon which semiconductor devices are fabricated), but metal-insulator electronics can be made atop less pricey glass, metal or plastic substrates. Phiar’s approach is to place two metal layers on either side of a double layer of insulation. When voltage is applied, electrons tunnel through the insulator layers with the help of a "quantum well" that forms between the two insulators.

Phiar will not specify which metals it uses, it is a trade secret, but says they are amorphous rather than crystalline, like silicon. This means these metals can be layered on top of a variety of other substances, including standard complementary metal–oxide semiconductor (CMOS) circuitry. As such, Phiar’s metal-insulator diodes or other electrical components could be combined with semiconductors on the same microchip. Among other potential options: using metal-insulator radios to replace the copper chip-to-chip interconnect wires on today’s printer circuit boards, eliminating one of computing’s worst performance bottlenecks. In the more distant future, metal-insulator devices could even replace the digital transistors within a semiconductor.

Phiar’s technology is expected to hit the market through a series of partnerships. Phiar and Motorola, Inc., last year signed a joint development agreement that could make Phiar’s metal-insulator electronics an integral part of the 60-gigahertz mobile wireless high-definition multimedia interfaces and imaging technologies that Motorola is developing. Motorola has successfully incorporated Phiar’s metal-insulator diodes into a 60-gigahertz prototype system and demonstrated multigigabit-per-second data rates.

The ability to operate at 60 gigahertz—where wavelengths are only a few millimeters—is crucial to the wireless personal area networks (PANs) that Motorola and other tech vendors are looking to offer. Whereas Wi-Fi signals—which operate at frequencies no greater than 5.8 gigahertz—can penetrate walls, glass and other barriers, enabling one wireless access point to serve an entire household, 60-gigahertz signals are more easily contained. This means a household could have one 60-gigahertz network in one room and an entirely different 60-gigahertz setup in the next room (hence the name "personal area" network). Operating in the wider bandwidth 60-gigahertz range also increases the speed of Wi-Fi data transfers.

"The seminal point about moving to higher frequencies is that there is more bandwidth available, which means it’s faster," Moddel says. This translates into content that is delivered faster over wireless networks, which is important because the demand for large data files and video content is on the rise.

Phiar’s technology is optimal for building radios because metal-insulator electronics can detect higher frequency signals than silicon-based semiconductors can. "Phiar’s technology vastly bumps up the speed at which you can detect an incoming signal," Ian Lao, a senior analyst with In-Stat, a technology research firm based in Scottsdale, Ariz., and a division of tech publisher Reed Elsevier, Inc. This has many implications in the development of new sensors and telecommunications equipment that will be able to quickly detect and accurately read wireless signals.

This could be a useful component in a high-speed communications network, "the kind of thing that a wireless company would want for their base stations," says Michael Kozicki, an Arizona State University professor of electrical engineering and director of the school’s Center for Applied Nanoionics. Phiar technology could become a central part of imaging systems such as airport security devices that rely on radiation moving at terahertz speeds to scan passengers for contraband, penetrating materials otherwise opaque to visible or infrared radiation.

Motorola and Phiar’s approach is expected to face competition from a number of companies eager to take wireless communications beyond Wi-Fi speeds. IBM and Taiwanese semiconductor maker Mediatek, Inc., are developing their own very fast chip sets that can wirelessly transmit a full-length, high-definition movie to and from a home PC, handheld device, retail kiosk or television set. IBM and Mediatek plan to ultimately develop ways to wirelessly connect high-definition TVs to set-top boxes using millimeter-wave radio technology, which takes advantage of the highest frequency portion of the radio spectrum where massive amounts of information can be sent quickly.

The companies will integrate IBM’s millimeter-wavelength radio chips, antenna and package technology with Mediatek’s digital base band and video processing chips. IBM demonstrated a prototype packaged chip set as small as a dime to wirelessly transmit uncompressed HD video two years ago.

"Don’t sell your stock in all of those silicon companies because this is not a replacement for silicon in any way, shape or form," Kozicki says. Although Phiar’s metal-insulator technology could become a crucial component of future high-frequency imaging systems or communications networking equipment, it is not meant to perform the kind of processing that silicon does so well.

Via Scientific American

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The Transition is not a flying car. The vehicle, set to go on sale next year, will cruise smoothly on the road and through the sky. It will have four wheels, Formula One–style suspension, and a pair of 10-foot-wide wings that fold up when it switches from air to asphalt. And when the engineers at Terrafugia in Woburn, Massachusetts, let me sit inside their just-finished proof-of-concept vehicle and grab the steering wheel, it’s easy to imagine piloting this thing up and out of traffic, into the open skies.

But we’re not talking about a flying car. The Transition is a “roadable aircraft.” The team makes this distinction clear in conversation, on Terrafugia T-shirts, and in big, blue letters on the side of the trailer outside their shop.
The flying car has been a mainstay of our imagined transportation future for as long as there have been automobiles and airplanes: fanciful vehicles that promise to have us commuting like George Jetson. Scores of garage inventors have spent their lives creating detailed designs, scale models, even working prototypes. In the 1950s, Molt Taylor, a former Navy pilot, flew a few versions of his Aerocar, an plane/car hybrid that attached to a separate, towable set of wings and a tail. But he couldn’t sign up enough customers to turn it into a business.

Now, the people who are closest to making that dream real—putting a car in the air, whatever they call it—are about the least starry-eyed folks you could meet. Terrafugia co-founder Carl Dietrich, 31, winces at that idea. “I’d hesitate to call any of us visionaries,” he says. “We’re engineers.”

Clean Up: Marc Stiller sands a component while Carl Dietrich (kneeling) and Andrew Heafitz look on. 

Dietrich’s company isn’t hinging its plans on out-of-reach technology or infrastructure. You won’t find any ducted fans or references to antigravity. He and his team are instead building a single-engine, rear-propeller airplane that just happens to be street-legal. They perfected the design in software simulators and are using materials proven in earlier vehicles. The Transition will meet Federal Aviation Administration standards in airplane mode and satisfy National Highway Transportation Safety Administration and Environmental Protection Agency regulations on the road. You’ll be able to take off only from a runway, and you’ll need a pilot’s license to do so. If you’re stuck in traffic, you’ll remain stuck. As they say, a roadable aircraft.

Unfortunately, that sober approach doesn’t make their task any easier. Dietrich’s team intends to manufacture and sell several hundred Transitions a year. That means doing things that no flying-car hopefuls before them ever have: Build an aircraft that can take potholes and protect its occupants if it slams into a brick wall at 30 miles an hour. Do it cheaply and reliably, again and again. Score passing grades from all those federal agencies. Find someone to insure it.

And yet they’re doing it. As this article goes to press, a full-scale, fully functional proof-of-concept vehicle is being readied for a flight test in November. Every expert I spoke to expects the design to fly. More than 40 customers have put down a good-faith deposit of $7,500 to $10,000 for a Transition, and the company has roughly $1 million in private funding. The investors have been told that the first customers will be driving it next year. In a category marked by decades-long efforts, it’s an insane schedule. But the group has hit every one of its benchmarks since starting out two years ago, methodically pushing through its plan. Dietrich and his partners have adorned their bumpers with the message “My next car will be an airplane.” To them, this is not a joke. It’s the headline to a list of promises they intend to keep.

1. The Transition will fit in your garage.

In 2004, the 27-year-old Dietrich, then an aeronautics graduate student at the Massachusetts Institute of Technology, began formulating a new kind of airplane design based on a rigid list of directives. Among them: It had to fit inside the average suburban garage, 7 by 19 feet. (Besides saving on hangar fees, how better to one-up your neighbor’s Porsche?)
His inspiration came from, of all things, an FAA rule change. That year, the flight agency designated a new class of planes, called light-sport aircraft. To fly one, pilots would need only 20 hours of training, half that required for the most common license. The FAA wanted to open the sport of flying to more people, and in one of its stipulations, Dietrich spotted a market for a driving plane. The sport-pilot license requires pilots to land immediately if the weather turns bad. Dietrich figured that, if given the option, these pilots would choose a plane they could simply drive home.

Dietrich knew that to sustain a small company, his plane had to be inexpensive to manufacture and repair. That eliminated mechanically complex options like long, thin telescoping wings. By 2005, he had tested more than 50 designs in computer simulations. The final configuration was the only one that fit the requirements of the road, the runway and the business. He built a scale model, and it aced wind-tunnel tests.

“You could see from the beginning that he was going about it in a professional way,” says Manuel Martinez-Sanchez, who directs MIT’s Space Propulsion Laboratory, “and that he wasn’t just a crank tinkering in his garage.” Dietrich was already a prolific inventor whose creations included a rocket engine and a simple tool that United Nations workers now use to deactivate land mines. That work, along with the Transition design, earned him MIT’s prestigious Lemelson Student Prize, an annual $30,000 award to the school’s most inventive young engineer. He took the check and started his company, along with Sam Schweighart, a jack-of-all-trades engineer whom he had met in MIT’s Rocket Club. By the end of 2005, he had also convinced classmate Anna Mracek to join, and they were married soon after. (She’s an iron-fisted project manager—she cuts off nerdy arguments to keep meetings tight, and her posted instructions for cleaning the bathrooms are a nine-point checklist.)

By the time I tour the company’s shop last November, the team has grown to eight engineers, including Andrew Heafitz, who spent the past decade building solar and electric cars, and composites wizard John “Turtle” Telfeyan, who designed America’s Cup boats for 20 years. But the only Transition I see is a radio-controlled one-fifth-scale model hanging from the ceiling. Computer screens reveal details of the engine’s innards. But there’s almost no hardware; they’re still shaping and baking the molds for the Transition’s composite frame.
What jumps out, though, is a working, full-scale, folding wing, and Dietrich proudly demonstrates it smoothly unfolding and locking into place. When we discuss the jump from crafting a single wing to cranking out hundreds of vehicles, though, his excitement dampens. Despite the impressive wing, the venture-capital money just isn’t coming in. Too many would-be investors (and customers) are doubtful that Terrafugia will succeed. “We can build one,” Dietrich insists. “We can make it work.”

2. The Transition will run on gasoline and fly for 460 miles. It will cost $194,000.

The Transition is meant to replace your current airplane, not your car. You could buy a Lexus and a little Cessna for the same price, but if that’s how you think, you’re not one of Terrafugia’s customers. Like Kansas City real-estate developer Mike McNicoll, who wants to fly to famous golf courses in Texas and Arizona. He also plans to soar to the greens just 35 miles from his house. “I’ll fly to an airport a few miles away and drive it right up to the club house,” he says. “I’ll deploy the wings a few times once I’m there, too.”

Impressed with how Terrafugia was meeting its deadlines—the wind-tunnel tests, the radio-controlled scale model, the working wing—McNicoll also signed on as an early investor. “Everything they said they were going to do along the way, they not only did it, but they did it by the time they said they would do it,” he says.

Paying customers are vital to Terrafugia’s plan, and so is making sure they can legally drive what they buy. “This whole process will grind to a halt if we can’t get it insured,” says Richard Gersh, Terrafugia’s vice president of business development. The 56-year-old Gersh, an amateur pilot with 30 years in the insurance industry, cornered Schweighart and the Dietrichs at a 2006 conference. Would the Transition fall under an aviation policy? he asked. An automotive one? They responded with blank stares. He offered his services.

Gersh now spends his days trying to anticipate every insurance and regulatory question that could keep the Transition off the road. He knows, for instance, that any insurer will ask how long it will take to replace a damaged wing and how much it will cost, so he has to get those estimates out of the engineers.

This spring, he managed to get the Dietrichs into Q&A sessions with regulators from the NHTSA and the EPA. Now they’re working with the NHTSA on whether video cameras and windshield-mounted screens can take the place of side-view mirrors, which are an aerodynamic nightmare, and with the EPA on whether the Transition will be classified as an airplane, which is held to looser emissions standards than automobiles are. For months, the EPA wouldn’t even return his calls, but Gersh eventually talked his way into a meeting with the official in charge of auto-emissions certificates. “I can’t go to Carl and say, ‘We can’t operate this as a car,’ ” Gersh says. “You can’t just take no for an answer.”

Control Freak: A mock-up of the control panel. Anyone can drive the Transition, but you’ll need a key code to deploy the wings. 

3. The Transition will be safe, and drive like a normal car in nearly any weather.

This might be Terrafugia’s boldest claim. To qualify as “light sport,” the Transition will have to weigh around 1,300 pounds. That’s 500 pounds less than a Smart car, but the Transition will be as long as a Suburban and, in places, just as tall. That calls into question whether it can survive a strong breeze, never mind a head-on collision with an SUV. In trying to be both an automobile and an aircraft, the Transition could wind up a mediocre version of both. “You look at the set of rules for designing a car and those for an airplane, and they’re not all that similar,” says Virginia Tech University aerospace engineering professor James Marchman, who in 1999 led a yearlong academic project to design a roadable aircraft.
Dietrich believes his design circumvents those rules. Take the assumption that only heavy cars are stable. With a low center of gravity, a long, wide wheelbase, a center of mass close to the front, and the canard wing, which generates downforce, Dietrich says that the featherweight Transition will stay glued to the pavement.

He’s also realistic about its limitations. “It’s got big fold-up wings and a tail in the back. It’s more sensitive to wind. We’re not going to deny that,” he says. In most areas, he adds, “there are only about seven days a year where it wouldn’t be safe to take on the road.”

What about that potential SUV run-in? Heafitz’s simulations show that the carbon-fiber-and-foam-core beams that make up the vehicle’s safety cage will protect passengers in side and head-on impacts, per NHTSA requirements. He’s built electric-car prototypes with the same material, and those produced such phenomenal test scores that the NHTSA didn’t believe the data. The only reason it’s not used more often, Heafitz says, is cost.

An NHTSA official tells me that the agency doesn’t care “if the cage is made out of bubble gum, as long as it passes crash tests.” Right now, though, Terrafugia can’t afford to intentionally wreck this proof-of-concept vehicle to see if it will. They need it as a sales tool. So by the end of the year, they’ll start building three prototypes—these are the ones they’ll beat to death. “I’m looking forward to it,” Heafitz says, “because that tells you how well you designed a car: how hard it is to break.”

During my next two visits, in March and April, there’s still little to see, much less destroy. The frame of the cockpit is finished, but it’s empty inside. Mock-up parts crafted out of plywood, plastic cups and tissue boxes stand in for the engine. Telfeyan gives a lesson on carbon-fiber application to a few new interns, but they look wary of touching the body. It’s as if they’re creating a sculpture, not an airplane.
But nearly all the parts are here, organized in bins on the wall—the transmission, the belt, the engine, the suspension, even the seats and wheels. It’s like a jigsaw puzzle; the board is laid out, the pieces ready to be fit together. “We’re going from having nothing in the plane to having everything ready to go in,” Schweighart says, staring wide-eyed at the shell as though he could see in it what I still could not: a road-ready vehicle, less than six months away.

4. The first Transition will fly in November. customers will have them by the end of 2009.

In early June, I drop in for “Weight on Wheels” day, the first test to see whether the vehicle supports itself; up until now, it’s been resting on a stand. For the first time, the Transition actually looks like, well, something. Without wings and a propeller, it reminds me of a plane crossed with a dune buggy.

The suspension and back wheels are in place, and an intern, Jordan Kusch, secures the front wheels. A TV crew is here. Dietrich is jittery. “You tightened all the lug nuts in the back, right?” he asks. Kusch nods. Minutes later, Schweighart repeats the question, “The rear wheels are tightened up?” “They are,” Kusch confirms. “I’ll go check,” Dietrich says.
After they triple-check the wheels, they carefully lift the proof-of-concept off its stand and gingerly set it on the floor. Nothing breaks, nothing cracks. “Weight on wheels!” whoops engineer Marc Stiller. For a few minutes, the shop is all smiles, cheers and flashing cameraphones. The Transition supports its own weight. That’s all it has to do today. But Dietrich isn’t satisfied. He kneels by the nose and starts pushing it up and down. He wants to see whether the first pothole will do it in. Nothing this rigorous was on the schedule, though, and the operations manager in his wife looks wary. “Uh, Carl?”

But the initial bounce goes well, so Dietrich motions for a few of the others to join him. They glance at one another nervously, then shrug and follow their leader. With two men on a side, they hoist the back of the vehicle a few feet off the floor, drop it, and breathe again as it lands, bounces to a stop—and holds together. Dietrich beams.

Eight weeks later, there’s a freshly painted, gleaming white, gorgeous airplane parked where the dune buggy used to be. I’ve come the morning the team is leaving for Oshkosh, Wisconsin, where they have committed to unveiling a finished vehicle at the Experimental Aircraft Association show. The crew has been working all night. Around 11 a.m., Schweighart sinks to the floor for a brief nap while Dietrich passes out in a chair surrounded by coffee cups. Everything but the prop shaft is installed. The body and engine are complete, the electronics are operational, and the remote-control doors open without a hitch.

The event is the Transition’s reveal to the world, and it’s critical for the business, since tens of thousands of pilots and potential customers will be there. Two interns push the vehicle out of the shop and up into the garage-size trailer. Neighbors and deliverymen gawk. The sky is blue and clear, the day perfect for the Transition to unfold its wings and take to the air. It almost could, and the team would love to do it, to show everyone right now how real this is. But they won’t turn on the engine for another month. That’s the plan: Show it off, then drive it, then fly it. Ticking off benchmarks until they finally have a few hundred pilots behind the wheel of what is—OK, yes—a flying car.

Via Popular Science

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Whether it’s the blue, ragged fingernails of a heroin-overdose victim or the scaly skin of someone poisoned by arsenic, a corpse bears signs that unveil the secrets behind its life and death. Right now, 40,000 John and Jane Does wait in morgues. Although accident and murder victims are 15 to 30 times as likely to be autopsied as those who die of natural causes, even run-of-the-mill autopsies can yield important information on how a person died. This data has important implications for public health and safety and the legislation that governs those areas of interest. Autopsy findings have led to tougher military gear, fire-resistant clothing, crashworthy fuel systems and child-safe toys. They have also helped reveal how HIV, tuberculosis and West Nile virus are transmitted. Medical examiners are always looking for smarter, faster and more reliable ways to uncover the truth.

Here are five technologies that epitomize the old morgue maxim Mortui vivos docent: The dead teach the living.

Hair:

Tracking a person’s movements
Hair illustrates the route people took before they died by revealing what water they drank. In February, researchers from the University of Utah and scientific-analysis company IsoForensics reported that the isotope ratios of oxygen and hydrogen in hair can link a person to regional water sources—sometimes down to sections of a given American state. Scientists can also track a person’s travels over long periods: The tips of the hair show older destinations; the roots, more recent ones.

Teeth:

ID’ing a body
Dental recognition goes back to the Romans. Last November, scientists from Kanagawa Dental College in Japan presented software that works 95 percent faster than manual methods. Within minutes, it locates three image matches from a database of dental records, which a forensic dentist then analyzes.

Brain:

Finding time of death
Establishing time of death is a notoriously dicey part of forensics and is usually accurate only up to three days postmortem. Scientists at the University of Bern Institute of Forensic Medicine in Switzerland are applying magnetic-resonance spectroscopy to “read” decomposition in the brain, making it easier to determine the time of death even three weeks after it occurs.

Heart:

Explaining the inexplicable
Researchers at the Mayo Clinic in Minnesota who study sudden, unexplained deaths in people under age 40 discovered last year that in up to a third of cases, postmortem genetic testing revealed that inherited heart-rhythm conditions contributed to death. These conditions, such as Long QT syndrome, go unnoticed by conventional autopsies. Finding them allows relatives to get tested themselves and seek out treatments.

Eyes:

Determining age
Carbon dating could help identify thousands of unknown bodies. All humans ingest small quantities of the carbon isotope carbon-14 through food. Most tissues constantly regenerate, but carbon-14 accumulates in teeth and the lenses of eyes. By analyzing the carbon-isotope ratios in lens tissue, researchers at the University of Copenhagen in Denmark have discovered that they can establish, to within 1.5 years, when someone was born—much better than the five years possible with commonly used methods.

The Autopsy: a Brief History

300 B.C.

 

 

Greek physicians Erasistratus and Herophilus pioneer anatomical autopsies by dissecting cadavers to study the workings of their organs and nerves. Later, second-century physician Galen becomes the first to link patients’ symptoms with autopsy observations.

 

 

 

 

 

 

 

 

 

1761

Giovanni Morgagni, an Italian anatomist, writes On the Seats and Causes of Diseases, a groundbreaking tome that details his exhaustive experience with autopsies and helps the discipline of anatomical pathology gain acceptance in the West.

 

 

 

 

 

 

1910

American physician Richard Cabot studies 1,000 autopsies and finds that the deceased’s doctors were wrong 40 percent of the time. Establishing cause of death becomes essential to correcting medical misinformation and improving diagnostic methods.

 

 

 

 

 

1987

Toxicology testing proves its mettle after a pathologist in Ohio detects cyanide in the body of hospital patient John Powell. His killer, hospital orderly Donald Harvey, is caught and convicted of fatally poisoning 23 people.

 

 

 

 

 

 

2005-2007

Technology explores two ancient mysteries: CT scans reveal what probably killed King Tut (an infected leg, not murder) and Oetzi, a 5,300-year-old man found preserved in the Italian Alps (a wound and head trauma, not exposure).

 

 

 

 

Via Popular Science

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One of the most promising technologies for the aspiring outer-space commuter is the space elevator. The concept, like quite a few others, was pressed into the public imagination by Arthur C. Clarke, who in his 1979 novel The Fountains of Paradise described a incredibly thin, incredibly strong carbon filament with one end anchored on Earth and the other extending up to a satellite in geostationary orbit. Now, a group of Japanese scientists are convinced that they can build a space elevator more quickly and cheaply than has been believed possible.

Such a cable could convey cargo into space very cheaply and easily. Carriages would travel up and down the cable under modest power, not the vast expenditures of energy that are currently needed to send anything into orbit.

Technology has crept closer to making it a reality: we have geostationary satellites, and carbon nanotubes promise to be strong and light enough to form the filament, if they can be produced in sufficient quantity. A space elevator would be tens of thousands of miles long.

A few initiatives already exist to make a space elevator a reality. Elevator:2010 sponsors annual contests; LiftPort promises to have an elevator built by October 27, 2031, and is selling tickets on it, at $25/ounce.

The Japan Space Elevator Association, a new player in the field anticipates that Japan’s industrial and research power — "using the technology employed in our bullet trains," according to Association director Yoshio Aoki — will be able to surmount the outstanding obstacles. The carbon fiber, which needs to have 180 times the tensile strength of steel, is currently under development by Japanese textile companies. The total price tag estimated for erecting the elevator is being estimated at just a trillion yen, or about 10 billion dollars.

From Times Online

From cyborg housemaids and waterpowered cars to dog translators and rocket boots, Japanese boffins have racked up plenty of near-misses in the quest to turn science fiction into reality.

Now the finest scientific minds of Japan are devoting themselves to cracking the greatest sci-fi vision of all: the space elevator. Man has so far conquered space by painfully and inefficiently blasting himself out of the atmosphere but the 21st century should bring a more leisurely ride to the final frontier.

For chemists, physicists, material scientists, astronauts and dreamers across the globe, the space elevator represents the most tantalising of concepts: cables stronger and lighter than any fibre yet woven, tethered to the ground and disappearing beyond the atmosphere to a satellite docking station in geosynchronous orbit above Earth.

Up and down the 22,000 mile-long (36,000km) cables — or flat ribbons — will run the elevator carriages, themselves requiring huge breakthroughs in engineering to which the biggest Japanese companies and universities have turned their collective attention.

In the carriages, the scientists behind the idea told The Times, could be any number of cargoes. A space elevator could carry people, huge solar-powered generators or even casks of radioactive waste. The point is that breaking free of Earth’s gravity will no longer require so much energy — perhaps 100 times less than launching the space shuttle.

“Just like travelling abroad, anyone will be able to ride the elevator into space,” Shuichi Ono, chairman of the Japan Space Elevator Association, said.

The vision has inspired scientists around the world and government organisations including Nasa. Several competing space elevator projects are gathering pace as various groups vie to build practical carriages, tethers and the hundreds of other parts required to carry out the plan. There are prizes offered by space elevator-related scientific organisations for breakthroughs and competitions for the best and fastest design of carriage.

First envisioned by the celebrated master of science fiction, Arthur C. Clarke, in his 1979 work The Fountains of Paradise, the concept has all the best qualities of great science fiction: it is bold, it is a leap of imagination and it would change life as we know it.

Unlike the warp drives in Star Trek, or H.G. Wells’s The Time Machine, the idea of the space elevator does not mess with the laws of science; it just presents a series of very, very complex engineering problems.

Japan is increasingly confident that its sprawling academic and industrial base can solve those issues, and has even put the astonishingly low price tag of a trillion yen (£5 billion) on building the elevator. Japan is renowned as a global leader in the precision engineering and high-quality material production without which the idea could never be possible.

The biggest obstacle lies in the cables. To extend the elevator to a stationary satellite from the Earth’s surface would require twice that length of cable to reach a counterweight, ensuring that the cable maintains its tension.

The cable must be exceptionally light, staggeringly strong and able to withstand all projectiles thrown at it inside and outside the atmosphere. The answer, according to the groups working on designs, will lie in carbon nanotubes - microscopic particles that can be formed into fibres and whose mass production is now a focus of Japan’s big textile companies.

According to Yoshio Aoki, a professor of precision machinery engineering at Nihon University and a director of the Japan Space Elevator Association, the cable would need to be about four times stronger than what is currently the strongest carbon nanotube fibre, or about 180 times stronger than steel. Pioneering work on carbon nanotubes in Cambridge has produced a strength improvement of about 100 times over the last five years.

Equally, there is the issue of powering the carriages as they climb into space. “We are thinking of using the technology employed in our bullet trains,” Professor Aoki said. “Carbon nanotubes are good conductors of electricity, so we are thinking of having a second cable to provide power all along the route.”

Japan is hosting an international conference in November to draw up a timetable for the machine.

Stranger than fiction

“Riding silently into the sky, soon she was 100km high, higher even than the old pioneering rocket planes, the X15s, used to reach. The sky was already all but black above her, with a twinkling of stars right at the zenith, the point to which the ribbon, gold-bright in the sunlight, pointed like an arrow. Looking up that way she could see no sign of structures further up the ribbon, no sign of the counterweight. Nothing but the shining beads of more spiders clambering up this thread to the sky. She suspected she still had not grasped the scale of the elevator, not remotely.”

Via Times Online and Popular Science

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A garden hose, a tin can, duct tape, metal piping, kitchen cleaner, and gasoline: That is all television icon MacGyver needed to make a flame-thrower to ward off a swarm of killer ants. In the real world, technologies that are affordable and practical are not so simple to create, but they can make a huge impact on people’s lives. Instead of calling on complex solutions (reliant on engines and imported resources) for low-tech problems (such as cooking and lighting), some researchers are now developing what they call "confluent" technologies—ones that are effective, affordable, and sustainable for use in the developing world. Here’s a look at the latest breakthroughs:

1  Energy in a Bucket of Dirt
Who needs nickel cadmium batteries or coal plants for electricity when you have soil? A Harvard team of faculty and African students have tapped into soil-dwelling microbes in order to provide electricity for families in Tanzania. When the microbes found in the soil digest organic materials, they naturally produce a small current, which can be harnessed with a simple device consisting of two electrodes and a small circuit board. One trash-barrel-sized unit filled with soil can produce enough electricity to light two bedrooms for a decade or more, says Harvard biology professor Peter Girguis. While each unit currently costs about $50, the team is testing new materials that would drive the price down to $7.

2  Micro-Hydroelectric Power
Hilly land streaked with small streams makes an ideal spot for micro-hydroelectric power generators, each of which requires a meager water flow of just three gallons per second to turn. (To put this in perspective, the Mississippi’s average flow at New Orleans is about 4.4 million gallons per second.) The Appropriate Infrastructure Development Group (AIDG) has helped to build three systems in Guatemala, and more communities are now saving up money for local installations.

3  Biodigesters
At the end of Back to the Future, a little bit of garbage is all Doc Brown needs to fuel his DeLorean time machine. Biodigesters won’t quite generate "1.21 jigawatts" of power (as Doc’s Mr. Fusion device seemed to), but they can create fuel for heating, cooking, and electricity while reducing waste and water contamination. In the salchicha-type biodigester (salchicha means "sausage" in Spanish), bacteria break down waste in a 15-to-30-foot-long polyethylene tube and release methane, which is captured and piped to a stove. The digested waste can then be used as a fertilizer. Biodigesters have been around since the 1870s, but current efforts focus on producing them on a larger scale. An award-winning system installed in Rwandan prisons reduced the need for firewood by half.

4  Wind Power on $2 a Day
Who said wind turbines have to spin? Shawn Frayne, founder of Humdinger Wind Energy, developed a turbine-less generator that harnesses energy from the rapid wind-induced vibration (50 cycles per second) of a seven-to-ten-foot flap of taffeta fabric. This is the same phenomenon—aeroelastic flutter—that civil engineers try to eliminate so bridges don’t sway in the wind, and on a small scale, it greatly increases the efficiency of capturing power from wind for a very small cost, says Frayne. "For people making a dollar or two a day, it could be in the realm of possibility to have electricity," says Peter Haas of AIDG, who is helping Frayne test the generators in Guatemala. Depending on wind conditions, the generators can be positioned to power efficient lights in a few rooms on small electrical grids. Frayne hopes to make the product available within a few years.

5  Sunlight Stored in LEDs
In rural Indian homes, kerosene lamps are ubiquitous, posing health concerns from fumes as well as a fire risk. Solar-charged lights designed by Patrick Walsh, founder of Greenlight Planet, are one solution to this problem. The lights run for four hours on their brightest setting after charging in the sun all day. The lights also reduce fuel costs for families and pay for themselves in just one year. After testing the market with 20 lamps, Walsh is now scaling up production.

6  Solar Water Heater
Solar water heaters are generally expensive (they can cost $400–$1,000), barring easy access to hot water for many who are far from an electric grid. But engineer Ashok Gadgil at the University of California, Berkeley, working with AIDG, cut back on materials and came up with a solar heater that costs $100. It can produce 26 gallons of water warmed to 104 degrees Fahrenheit by 4 p.m. each day—enough for four showers. Tests are ongoing in Guatemala, after which the team plans to fine-tune the design and begin distribution.

7  Pedal-Powered Grid
People who live off the grid in rural corners of the world may soon have a new source of energy: 12-volt batteries charged by pedaling. Using a simple alternator, six hours of pedaling can create and store enough electrical energy in batteries to light about six homes for 30 days (in areas where people use less electricity than in the U.S.). Dissigno, the San Francisco–based company that distributes the devices, has one prototype up and running in Haiti and next hopes to install a "grid" in Tanzania connected by a network of pedalers instead of power lines.

8  Sugarcane Charcoal

In Haiti, most people cook using charcoal made from wood, but the country is now 98 percent deforested due largely to mismanagement of resources. MIT students and lecturer Amy Smith turned to widely available bagasse, the stalks of sugarcane plants left after squeezing the sugar out, and created a charcoal replacement by burning, compressing, and mixing the material with a binding agent. The team is currently looking to train prospective entrepreneurs interested in producing and distributing the product.

9  Irrigation by Foot
Most African farmers rely on seasonal rainfall, having no other means of irrigation for crops. So Martin Fisher, the CEO of KickStart International, came up with a device you can pump with your feet that pulls water from 30 feet underground with enough pressure to irrigate up to two acres of land. This enables more frequent harvests of high-value crops like vegetables rather than grains. In Africa, more than 65,000 such pumps are currently in use. Fisher won the 2008 Lemelson-MIT Award for Sustainability for the invention.

10  Chlorine from Salt
For the roughly 1.2 billion people lacking clean water, a bit of chlorine could go a long way toward providing it. Using two ounces of salt water and some muscle, University of Iowa engineering professor Craig Just can make enough bleach to kill the disease-causing microorganisms in five gallons of water. His trick: a hand-cranked device that generates electricity to zap water molecules, splitting them and joining them with chlorine atoms from salt. Just and his students plan to test a prototype in Ghana and Honduras next year.

Via Discover Magazine

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• The Large Hadron Collider (LHC), the biggest and most complicated particle physics experiment ever seen, is nearing completion and is scheduled to start operating this year.
• The LHC will accelerate bunches of protons to the highest energies ever generated by a machine, colliding them head-on 30 million times a second, with each collision spewing out thousands of particles at nearly the speed of light.
• Physicists expect the LHC to bring about a new era of particle physics in which major conundrums about the composition of matter and energy in the universe will be resolved.

You could think of it as the biggest, most powerful microscope in the history of science. The Large Hadron Collider (LHC), now being completed underneath a circle of countryside and villages a short drive from Geneva, will peer into the physics of the shortest distances (down to a nano-nanometer) and the highest energies ever probed. For a decade or more, particle physicists have been eagerly awaiting a chance to explore that domain, sometimes called the tera­scale because of the energy range involved: a trillion electron volts, or 1 TeV. Significant new physics is expected to occur at these energies, such as the elusive Higgs particle (believed to be responsible for imbuing other particles with mass) and the particle that constitutes the dark matter that makes up most of the material in the universe.

The mammoth machine, after a nine-year construction period, is scheduled (touch wood) to begin producing its beams of particles later this year. The commissioning process is planned to proceed from one beam to two beams to colliding beams; from lower energies to the tera­scale; from weaker test intensities to stronger ones suitable for producing data at useful rates but more difficult to control. Each step along the way will produce challenges to be overcome by the more than 5,000 scientists, engineers and students collaborating on the gargantuan effort. When I visited the project last fall to get a firsthand look at the preparations to probe the high-energy frontier, I found that everyone I spoke to expressed quiet confidence about their ultimate success, despite the repeatedly delayed schedule. The particle physics community is eagerly awaiting the first results from the LHC. Frank Wil­czek of the Massachusetts Institute of Technology echoes a common sentiment when he speaks of the prospects for the LHC to produce “a golden age of physics.”

A Machine of Superlatives
To break into the new territory that is the tera­scale, the LHC’s basic parameters outdo those of previous colliders in almost every respect. It starts by producing proton beams of far higher energies than ever before. Its nearly 7,000 magnets, chilled by liquid helium to less than two kelvins to make them superconducting, will steer and focus two beams of protons traveling within a millionth of a percent of the speed of light. Each proton will have about 7 TeV of energy—7,000 times as much energy as a proton at rest has embodied in its mass, courtesy of Einstein’s E = mc2. That is about seven times the energy of the reigning record holder, the Tevatron collider at Fermi National Accelerator Laboratory in Batavia, Ill. Equally important, the machine is designed to produce beams with 40 times the intensity, or luminosity, of the Tevatron’s beams. When it is fully loaded and at maximum energy, all the circulating particles will carry energy roughly equal to the kinetic energy of about 900 cars traveling at 100 kilometers per hour, or enough to heat the water for nearly 2,000 liters of coffee.

The protons will travel in nearly 3,000 bunches, spaced all around the 27-kilometer circumference of the collider. Each bunch of up to 100 billion protons will be the size of a needle, just a few centimeters long and squeezed down to 16 microns in diameter (about the same as the thinnest of human hairs) at the collision points. At four locations around the ring, these needles will pass through one another, producing more than 600 million particle collisions every second. The collisions, or events, as physicists call them, actually will occur between particles that make up the protons—quarks and gluons. The most cataclysmic of the smashups will release about a seventh of the energy available in the parent protons, or about 2 TeV. (For the same reason, the Tevatron falls short of exploring tera­scale physics by about a factor of five, despite the 1-TeV energy of its protons and antiprotons.)

Four giant detectors—the largest would roughly half-fill the Notre Dame cathedral in Paris, and the heaviest contains more iron than the Eiffel Tower—will track and measure the thousands of particles spewed out by each collision occurring at their centers. Despite the detectors’ vast size, some elements of them must be positioned with a precision of 50 microns.

The nearly 100 million channels of data streaming from each of the two largest detectors would fill 100,000 CDs every second, enough to produce a stack to the moon in six months. So instead of attempting to record it all, the experiments will have what are called trigger and data-acquisition systems, which act like vast spam filters, immediately discarding almost all the information and sending the data from only the most promising-looking 100 events each second to the LHC’s central computing system at CERN, the European laboratory for particle physics and the collider’s home, for archiving and later analysis.

A “farm” of a few thousand computers at CERN will turn the filtered raw data into more compact data sets organized for physicists to comb through. Their analyses will take place on a so-called grid network comprising tens of thousands of PCs at institutes around the world, all connected to a hub of a dozen major centers on three continents that are in turn linked to CERN by dedicated optical cables.

Journey of a Thousand Steps
In the coming months, all eyes will be on the accelerator. The final connections between adjacent magnets in the ring were made in early November, and as we go to press in mid-December one of the eight sectors has been cooled almost to the cryogenic temperature required for operation, and the cooling of a second has begun. One sector was cooled, powered up and then returned to room temperature earlier in 2007. After the operation of the sectors has been tested, first individually and then together as an integrated system, a beam of protons will be injected into one of the two beam pipes that carry them around the machine’s 27 kilometers.

The series of smaller accelerators that supply the beam to the main LHC ring has already been checked out, bringing protons with an energy of 0.45 TeV “to the doorstep” of where they will be injected into the LHC. The first injection of the beam will be a critical step, and the LHC scientists will start with a low-intensity beam to reduce the risk of damaging LHC hardware. Only when they have carefully assessed how that “pilot” beam responds inside the LHC and have made fine corrections to the steering magnetic fields will they proceed to higher intensities. For the first running at the design energy of 7 TeV, only a single bunch of protons will circulate in each direction instead of the nearly 3,000 that constitute the ultimate goal.

As the full commissioning of the accelerator proceeds in this measured step-by-step fashion, problems are sure to arise. The big unknown is how long the engineers and scientists will take to overcome each challenge. If a sector has to be brought back to room temperature for repairs, it will add months.

The four experiments—ATLAS, ALICE, CMS and LHCb—also have a lengthy process of completion ahead of them, and they must be closed up before the beam commissioning begins. Some extremely fragile units are still being installed, such as the so-called vertex locator detector that was positioned in LHCb in mid-November. During my visit, as one who specialized in theoretical rather than experimental physics many years ago in graduate school, I was struck by the thick rivers of thousands of cables required to carry all the channels of data from the detectors—every cable individually labeled and needing to be painstakingly matched up to the correct socket and tested by present-day students.

Although colliding beams are still months in the future, some of the students and postdocs already have their hands on real data, courtesy of cosmic rays sleeting down through the Franco-Swiss rock and passing through their detectors sporadically. Seeing how the detectors respond to these interlopers provides an important reality check that everything is working together correctly—from the voltage supplies to the detector elements themselves to the electronics of the readouts to the data-acquisition software that integrates the millions of individual signals into a coherent description of an “event.”

All Together Now
When everything is working together, including the beams colliding at the center of each detector, the task faced by the detectors and the data-processing systems will be Herculean. At the design luminosity, as many as 20 events will occur with each crossing of the needlelike bunches of protons. A mere 25 nanoseconds pass between one crossing and the next (some have larger gaps). Product particles sprayed out from the collisions of one crossing will still be moving through the outer layers of a detector when the next crossing is already taking place. Individual elements in each of the detector layers respond as a particle of the right kind passes through it. The millions of channels of data streaming away from the detector produce about a megabyte of data from each event: a petabyte, or a billion megabytes, of it every two seconds.

The trigger system that will reduce this flood of data to manageable proportions has multiple levels. The first level will receive and analyze data from only a subset of all the detector’s components, from which it can pick out promising events based on isolated factors such as whether an energetic muon was spotted flying out at a large angle from the beam axis. This so-called level-one triggering will be conducted by hundreds of dedicated computer boards—the logic embodied in the hardware. They will select 100,000 bunches of data per second for more careful analysis by the next stage, the higher-level trigger.

The higher-level trigger, in contrast, will receive data from all of the detector’s millions of channels. Its software will run on a farm of computers, and with an average of 10 microseconds elapsing between each bunch approved by the level-one trigger, it will have enough time to “reconstruct” each event. In other words, it will project tracks back to common points of origin and thereby form a coherent set of data—energies, momenta, trajectories, and so on—for the particles produced by each event.

The higher-level trigger passes about 100 events per second to the hub of the LHC’s global network of computing resources—the LHC Computing Grid. A grid system combines the processing power of a network of computing centers and makes it available to users who may log in to the grid from their home institutes [see “The Grid: Computing without Bounds,” by Ian Foster; Scientific American, April 2003].

The LHC’s grid is organized into tiers. Tier 0 is at CERN itself and consists in large part of thousands of commercially bought computer processors, both PC-style boxes and, more recently, “blade” systems similar in dimensions to a pizza box but in stylish black, stacked in row after row of shelves. Computers are still being purchased and added to the system. Much like a home user, the people in charge look for the ever moving sweet spot of most bang for the buck, avoiding the newest and most powerful models in favor of more economical options.

The data passed to Tier 0 by the four LHC experiments’ data-acquisition systems will be archived on magnetic tape. That may sound old-fashioned and low-tech in this age of DVD-RAM disks and flash drives, but François Grey of the CERN Computing Center says it turns out to be the most cost-effective and secure approach.

Tier 0 will distribute the data to the 12 Tier 1 centers, which are located at CERN itself and at 11 other major institutes around the world, including Fermilab and Brookhaven National Laboratory in the U.S., as well as centers in Europe, Asia and Canada. Thus, the unprocessed data will exist in two copies, one at CERN and one divided up around the world. Each of the Tier 1 centers will also host a complete set of the data in a compact form structured for physicists to carry out many of their analyses.

The full LHC Computing Grid also has Tier 2 centers, which are smaller computing centers at universities and research institutes. Computers at these centers will supply distributed processing power to the entire grid for the data analyses.

Rocky Road
With all the novel technologies being prepared to come online, it is not surprising that the LHC has experienced some hiccups—and some more serious setbacks—along the way. Last March a magnet of the kind used to focus the proton beams just ahead of a collision point (called a quadrupole magnet) suffered a “serious failure” during a test of its ability to stand up against the kind of significant forces that could occur if, for instance, the magnet’s coils lost their superconductivity during operation of the beam (a mishap called quenching). Part of the supports of the magnet had collapsed under the pressure of the test, producing a loud bang like an explosion and releasing helium gas. (Incidentally, when workers or visiting journalists go into the tunnel, they carry small emergency breathing apparatuses as a safety precaution.)

These magnets come in groups of three, to squeeze the beam first from side to side, then in the vertical direction, and finally again side to side, a sequence that brings the beam to a sharp focus. The LHC uses 24 of them, one triplet on each side of the four interaction points. At first the LHC scientists did not know if all 24 would need to be removed from the machine and brought aboveground for modification, a time-consuming procedure that could have added weeks to the schedule. The problem was a design flaw: the magnet designers (researchers at Fermilab) had failed to take account of all the kinds of forces the magnets had to withstand. CERN and Fermilab researchers worked feverishly, identifying the problem and coming up with a strategy to fix the undamaged magnets in the accelerator tunnel. (The triplet damaged in the test was moved aboveground for its repairs.)

In June, CERN director general Robert Aymar announced that because of the magnet failure, along with an accumulation of minor problems, he had to postpone the scheduled start-up of the accelerator from November 2007 to spring of this year. The beam energy is to be ramped up faster to try to stay on schedule for “doing physics” by July.

Although some workers on the detectors hinted to me that they were happy to have more time, the seemingly ever receding start-up date is a concern because the longer the LHC takes to begin producing sizable quantities of data, the more opportunity the Tevatron has—it is still running—to scoop it. The Tevatron could find evidence of the Higgs boson or something equally exciting if nature has played a cruel trick and given it just enough mass for it to show up only now in Fermilab’s growing mountain of data.

Holdups also can cause personal woes through the price individual students and scientists pay as they delay stages of their careers waiting for data.

Another potentially serious problem came to light in September, when engineers discovered that sliding copper fingers inside the beam pipes known as plug-in modules had crumpled after a sector of the accelerator had been cooled to the cryogenic temperatures required for operation and then warmed back to room temperature.

At first the extent of the problem was unknown. The full sector where the cooling test had been conducted has 366 plug-in modules, and opening up every one for inspection and possibly repair would have been terrible. Instead the team addressing the issue devised a scheme to insert a ball slightly smaller than a Ping-Pong ball into the beam pipe—just small enough to fit and be blown along the pipe with compressed air and large enough to be stopped at a deformed module. The sphere contained a radio transmitting at 40 megahertz—the same frequency at which bunches of protons will travel along the pipe when the accelerator is running at full capacity—enabling the tracking of its progress by beam sensors that are installed every 50 meters. To everyone’s relief, this procedure revealed that only six of the sector’s modules had malfunctioned, a manageable number to open up and repair

When the last of the connections between accelerating magnets was made in November, completing the circle and clearing the way to start cooling down all the sectors, project leader Lyn Evans commented, “For a machine of this complexity, things are going remarkably smoothly, and we’re all looking forward to doing physics with the LHC next summer."

Via Scientific American

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The baobab tree represents one of the most ancient species of life on the planet. Scientists have investigated ancient and highly divergent proteins, called retroelements, whose evolutionary histories hold keys to uncovering the origins of life. (Credit: Randen Patterson and Damian van Rossum, Penn State)

"We have just begun to tap the potential power of this method," said Randen Patterson, a Penn State assistant professor of biology and one of the project’s leaders. "We believe, if it is possible at all, that it is within our grasp to determine whether viruses evolved from cells or vice-versa."

The new computational method will be described in a paper to be published in a future issue of the journal Proceedings of the National Academy of Sciences. The journal also will post the paper on the early on-line section of its Web site sometime during the week ending 6 September 2008.

The team is focusing on an ancient group of proteins, called retroelements, which comprise approximately 50 percent of the human genome by weight and are a crucial component in a number of diseases, including AIDS. "Retroelements are an ancient and highly diverse class of proteins; therefore, they provide a rigorous benchmark for us to test our approach. We are happy with the results we derived, even though our method is in an early stage," said Patterson. The team plans to make the algorithms that they used in their method available to others as open-source software that is freely available on the Web.

Scientists map out the evolutionary histories of organisms by comparing their genetic and/or protein sequences. Those organisms that are closely related and share a recent common ancestor have greater degrees of similarity among their sequences. In their paper, the researchers describe how they used 11 groups of the retroelement proteins — ranging from bacteria to human HIV — to trace the evolutionary histories of retroelements. Their method uses a computer algorithm to generate evolutionary profiles — also called phylogenetic profiles — that are compared all-against-all. For example, given four sequences, the new method compares profile A to profiles B, C, and D; it compares profile B to profiles C and D; and so on, for a total of six comparisons. The method then selects the regions of the profiles that match and creates a tree-like diagram, called a phylogenetic tree, based on the retroelements’ similarities to one another. The tree provides evolutionary distance estimates and, hence, phylogenetic relationships among retroelements. Patterson said that the results from this study help to clarify many existing theories on retroelement evolution.

The conventional method for estimating evolutionary relationships, called multiple sequence alignment, also produces evolutionary trees, but can be insensitive to relationships among the most distantly related proteins, in large part because it makes only one simultaneous comparison across all of the genetic/protein sequences. To obtain more detailed information about possible relationships among the sequences, a human expert who can manually search for such relationships is needed. But Patterson said that relying on humans to do the work is not ideal.

"Although the human mind is the most powerful tool for pattern recognition, human-based measurements often are hard to reproduce," he said. "For example, if you do something and I do something, we’re going to do it differently. It’s better to have a standardized method for gauging relationships among ancient proteins, and that’s exactly what we’ve created." According to Damian van Rossum, Penn State research associate/assistant professor of biology and another leader on the project, the new method can be used in conjunction with the conventional method to get a clearer picture of the evolutionary histories of proteins. "The more independent measures you have, the better view of the world you can get," he said.

In addition to searching for the origins of life, the team also is using its method to simultaneously gather data on the shapes of proteins, their functions in the body, and their evolutionary histories. In another paper, which was published in 2008 in the online journal Physics Archives, members of the team previously had demonstrated that their new method can simultaneously measure all three of these characteristics. "Previously, people have shown that profiling methods can resolve functional and structural differences and similarities between proteins, but to date no one has shown that you can measure evolutionary distances," said van Rossum. "Not only can our method measure evolutionary distances, but it also can measure functional and structural characteristics at the same time."

Patterson said that there are about 30,000 profiles in an online scientific repository that they can use to generate their phylogenetic profiles. He expects that the team’s method will become even more powerful as additional sequences are added to this protein bank. In fact, the method already has become more refined in the short time since the team submitted its manuscript to the journal. "We already are producing evolutionary trees with much more detail than what we show in the paper," he said. "In fact, we are surprised at our progress so far in our goal of tracing these histories all the way back to the beginning of life."

This research was supported by the Commonwealth Universal Research Enhancement (CURE) Program, the Penn State Eberly College of Science, the Penn State Huck Institutes of the Life Sciences, and the Searle Scholars Program.

Via Science Daily

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True Color: The release of photons that results from the combination of hydrogen peroxide and chlorine causes a vivid orange-red glow.

Before the discovery in the 1920s of quantum mechanics—laws that explain the way the world works on the very small scale of atoms and electrons—the fact that bleach and peroxide glow when mixed would have seemed like just another chemical reaction that gives off light, like fire or fireflies. But it’s actually a glimpse into the impossible.

Hydrogen peroxide decomposes when it meets chlorine, releasing molecules of oxygen, each of which has one electron in a high-energy state. When the electrons inevitably return to a low-energy state, the excess energy comes off as a photon of light, creating a glow. Simple—but there are two problems.

First, quantum calculations show that the energy created in this transition is only enough for a photon of infrared light, which is invisible. Second, there are three separate laws of quantum mechanics that say this particular transition (a lone oxygen molecule going from high to low energy) can’t happen anyway.

Why should we believe in the abstract, common-sense-defying math of quantum mechanics? Because two impossibles sometimes make a possible.

It turns out that since the transition is forbidden, the molecule is stuck in its “excited” state—until, that is, it eventually collides with another excited molecule, breaking one of those laws (symmetry) and allowing two electrons to return to lower-energy states simultaneously. Together they release a single photon with twice the energy: a photon of visible orange-red light. Not so impossible after all.

This phenomenon is why we shouldn’t give up hope that things everyone knows can’t happen, like exceeding the speed of light, actually can. If mixing bleach and peroxide plunges us this deep into the weird, perhaps some future golden age of physics will prove that, unnoticed today, mixing red wine with a dry martini generates just a tiny little bit of faster-than-light travel.

Glowing Glass

To the right, the setup of the chemicals in the lab. Trying to make luminescent liquid doesn’t work well with regular bleach and peroxide. To get a bright glow, we bubbled pure chlorine gas through the glass tube into 30 percent peroxide.

ACHTUNG! Don’t try to replicate this experiment at home and do not drink any of these chemicals. Read more about Gray’s pursuits at periodictable.com.

Via Popular Science

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