Some office printers emit dangerous particles

A new study suggests that some printers emit dangerous particles that could make office workers sick.

Researchers at Queensland University of Technology in Australia found that 17 of the 62 printers they tested were "high particle emitters" that posed a threat to humans. They say 37 of the printers didn't emit any particles, but one gave off particles at the same rate as a burning cigarette.

"These printer particles are tiny like cigarette smoke particles and, when deep inside the lung, they do the same amount of damage. The health effects from inhaling ultra-fine particles depend on particle composition, but the results can range from respiratory irritation to more severe illness such as cardiovascular problems or cancer," Professor Lidia Morawska, the study's author, tells The Age.

Her research showed that particle levels were five times higher during working hours because of the emissions from printers. She says the printers were more likely to emit dangerous particles when the toner cartridge was new or the machines was being used to print detailed images.

"Printers should operate in environments where there is as much ventilation as possible and as far as possible from where people's desks are located." she tells tells Australian Broadcasting Corporation.

ABC Science has an extensive report on the findings.

Source : USA Today

The maths of modern architecture : Perfect Buildings

Architecture has in the past done great things for geometry. Together with the need to measure the land they lived on, it was people's need to build their buildings that caused them to first investigate the theory of form and shape. But today, 4500 years after the great pyramids were built in Egypt, what can mathematics do for architecture? Read More

The London City Hall

The London City Hall on the river Thames. Note the giant helical
stair case inside. Image © Foster + Partners.


Tiny magnets help drugs reach the spot

Inhaled drugs could soon be guided to the lungs by magnetic fields using a new technique developed by researchers in Germany. The team performed computer simulations and experiments on mice to show that drugs mixed with tiny magnetic nanoparticles could be delivered to the lungs up to eight times more efficiently than if inhaled normally.

Many pulmonary diseases, such as asthma, cystic fibrosis and lung cancer, need drugs to be inhaled so that they can reach the affected area. To do this, patients have to gasp on an inhaler that emits the particulate drugs into the windpipe.

But the effectiveness of these inhalers is not great: typically only 4% of the drug makes it through the windpipe, forcing doctors to administer higher doses, which can exacerbate unwanted side effects.

A better way, according to Carsten Rudolph at Ludwig-Maximilians University in Munich and co-workers from elsewhere in Germany, is to mix the drugs with magnetic nanoparticles, or "nanomagnetosols", in microdroplets of water. These microdroplets can then be guided directly to problem areas using a magnetic field. The idea is not new, but Rudolph's group show for the first time that it can be performed in a real organism – in this case, a mouse.

The researchers began by creating a computer simulation of a mouse's airways where the windpipe forks into two bronchi, taking into account air flow rates measured in previous physiological studies. Assuming they were to use iron-oxide nanomagnetosols with a diameter of 50 nm, they predicted that they could use a magnetic probe placed close to a bronchus to get up to 16% coverage of the microdroplets.

Rudolph's group tested their prediction by opening up the chest of a mouse, and placed a specially designed magnetic tip probe with a high flux gradient of 100 Tm-1 next to one of the lungs. When they squirted the microdroplets into the mouse's airways, they found that the lung next to the probe received eight times more drug coverage than the one without. Upon placing the probe on another mouse with its chest intact, the benefit was reduced, with just two and a half times more coverage.

Performing the same feat in humans will not be so straightforward, however. Human lungs are much larger and more intricate, so it will be difficult to guide the microdroplets with the same accuracy. Moreover, a much more powerful magnetic probe will be required to overcome the additional distance between the probe and inner lung.

Source : Physics Web

First photo of the whole Earth

Perhaps one of the most powerful images of all time, the first photo of the whole Earth, taken November 10, 1967, has had a significant impact on human consciousness. Stewart Brand, creator of the Whole Earth Catalog, had these observations about the image:

[It was] motivating for a lot of people, because it gave the sense that Earth is an island, surrounded by a lot of inhospitable space. And it’s so graphic, this little blue, white, green, and brown jewel-like icon amongst a quite featureless black vacuum. Islands know about limitations. Bucky [Buckminster Fuller] led me to this notion. He said people still think the earth is flat because they act as if its resources are infinite. But that photograph showed otherwise…. This is all we’ve got and we’ve got to make it work. There’s no backup. (Massive Change Radio, March 2, 2004)

After this image achieved wide-scale circulation, Earth Day was founded and gained a broad political following, enlisting support from all kinds of people who are moved by both the limitations and the uniqueness of our planet.

Google Earth Pictures China's Nuclear Weaponry

Increasingly, tools readily available on the Internet enable independent specialists or even members of the general public to do intelligence work that used to be the monopoly of agencies like the CIA, KGB, or MI6. Playing the role of an armchair James Bond, Hans K. Kristensen, a nuclear weapons specialist at the Federation of American Scientists (FAS) in Washington, D.C., recently drew attention to images on Google Earth of Chinese sites. Kristensen believes that the pictures shed light on China's deployment of its second-generation of nuclear weapons systems: one appears to be a new ballistic missile submarine ; others may capture the replacement of liquid-fueled rockets with solid-fuel rockets at sites in north-central China, within range of ICBM fields in southern Russia.

Kristensen, a native of Denmark, has worked on matters related to nuclear weaponry and arms control for the Nautilus Institute, in Berkeley, Calif., and the Natural Resources Defense Council, in Washington, D.C. He coauthors with NRDC staffers a regular update on global nuclear weapons developments for the Bulletin of the Atomic Scientists.

The FAS was founded in 1945 by scientists associated with the Manhattan Project who were concerned about the social and political implications of nuclear weapons. It has a staff of a couple of dozen specialists who work primarily on arms control and global security.

IEEE Spectrum: The photos of the missile sites suggest to you that China is replacing liquid-fueled rockets with more advanced solid-fueled ones, while the submarine seems to be one of a new class, the Jin or 094. Are these related developments? Can you describe the larger strategic context?

Hans K. Kristensen: China is in a transition phase from its first generation of nuclear weapons. Back in the 1980s China began a program to develop a more survivable nuclear deterrent. Its concern was that its liquid-fueled mobile missiles, which take a long time to prepare for launch, were becoming very vulnerable to preemptive attack, either from the United States or, at that time, the Soviet Union. We're seeing the products of that program begin to emerge. There are two new land-based, solid-fueled systems: one is the DF-21, which will be able to reach the northwestern parts of the United States, and later, a more advanced system that will be able to reach all of the United States. Concurrently, China developing a sea-based deterrent, using a new missile called the Julang 2.

IEEE Spectrum: What drew your attention to the Google images?

Kristensen: I looked at images of these sites regularly, and when I recently revisited, I saw changes compared with older images taken two years ago.

IEEE Spectrum: What do you see?

Kristensen: In the case of the missiles at the Delingha site, I noticed eight 13-meter trucks lined up on a launchpad that had been empty two years ago. The satellite image is not of high enough resolution to identify the trucks and their features with certainty, but they strongly resemble the six-axle transport erector launchers in use with the 10-meter DF-21 medium-range ballistic missile. The image showed significant changes at several sites in the area, although the jury is still out on exactly what it means.

The submarine image seems to have captured the new class, known as the Jin-class or Type 094, which is expected to replace the unsuccessful Xia-class (Type 092) of which only a single boat was completed in the early 1980s. The new sub is about 35 feet longer than the old boat, mainly due to a larger missile compartment.

IEEE Spectrum: You said earlier that initial Chinese nuclear deployments were made with both the United States and the Soviet Union in mind. Has China's threat perception changed any with the end of the Cold War?

Kristensen: They're still concerned about both, but perhaps somewhat more about the United States now. Russia has pulled back both conventional forces and tactical nuclear weapons from its borders with China, while the United States recently has increased its number of nuclear ballistic missile submarines in the Pacific.

IEEE Spectrum: Many of the Soviet Union's tactical nuclear weapons would have been based in the central Asian states that are now independent, would they not?

Kristensen: Yes, but Russia has also destroyed many of its nonstrategic nuclear weapons and pulled back the remaining to more central storage in depots.

IEEE Spectrum: Are there other reasons that China might be more focused on the United States?

Kristensen: They're very worried about our carrier groups steaming up and down their coasts, and they may also be concerned about our attack submarines. But there are also those who say that what they're doing with their nuclear weapons is simply what any country in their position would want to do to modernize forces. The Chinese nuclear posture has always been rather relaxed, and has never had the tit-for-tat character seen with the superpowers during the Cold War.

For example, their ICBMs in their silos are not thought to be loaded with nuclear warheads, which would first have to be installed to become operational.

On the other hand, replacement of liquid-fuel with solid-fuel rockets on the northern border means that they now can be readied for firing much faster, and Russian planners will take note. So something that the Chinese themselves might consider routine may have larger reverberations. By the same token, those medium-range missiles in north-central China can't reach the United States, but similar ones based further east can reach U.S. bases on Guam or Okinawa.

IEEE Spectrum: Are these developments having reverberations in China itself?

Kristensen: Yes, for example, there's a debate in its universities and military institutes about whether it should continue to adhere to its strict no-first-use-of-nuclear-weapons policy, which goes back to Mao. Should their posture become somewhat more flexible?

IEEE Spectrum: If, to take a very worst-case scenario, a war broke out over Taiwan, in which Korea or Japan got involved, China is on record saying it would not be the first to use nuclear weapons?

Kristensen: Yes. Its firm policy is no first use under any circumstances, but I can't see how China could adhere to that policy if its nuclear forces were under attack, even if only conventional weapons were involved.

IEEE Spectrum: What about China's launching a missile to destroy a commercial satellite in low-earth orbit this past January? Was that highly publicized event of a piece with its more aggressive nuclear stance?

Kristensen: It wasn't the first such demonstration. Both the United States and Russia did similar tests in the 1980s. If a conflict erupted over Taiwan, the Chinese would be worried about the U.S. ability to monitor their activities from space. But remember, their antisatellite capabilities are very far from a true war-fighting capability. They can't reach our GPS guidance satellites in high-earth orbits.

IEEE Spectrum: Even so, could that January test be a step in the direction of developing a missile defense capability, the way our tests in the 1980s were?

Kristensen: I don't see that, but remember that missile defense systems are very wide-ranging technologies that depend on many key elements, including early warning and tracking, where the Chinese are still extremely weak.

Source : IEEE Spectrum

The Physics of Slapshots and Mid-ice Collisions

When two NHL hockey players collide, their pads and body tissues can absorb enough energy to power a 100-watt light bulb for a minute and a half. During the 60 minutes of a hockey game, players can burn 6,000 calories and lose up to 15 pounds.

These are the calculations of Alain Hache, a physicist at the University of Moncton in New Brunswick, Canada. An amateur goalie, Hache has combined two of his passions in his book The Physics of Hockey.

Hache begins his look at one of the north’s favorite sports by examining the physical properties of ice, one of Alaska’s most abundant natural resources. Friction at the contact points between surfaces is what slows most sports down, but the low friction coefficient of ice makes hockey players faster on their feet than the athletes of any other team sport. Many NHL players can skate faster than 25 miles per hour, and Hall of Famer Bobby Hull was once clocked at 29.3 miles per hour. Scientists once tracked Hull during a game and calculated that he had skated more than eight miles during his 29 minutes on the ice.

While everyone agrees that ice is slippery, scientists have long debated the reasons why. Hache wrote about a study in the year 2000 by researchers at the University of California at Berkeley that revealed one of ice’s slicker secrets. The California scientists used an atomic microscope to find a thin, wet layer of quasi-fluid water on the surface of an ice crystal. That layer provides a lubricant, even when ice is very cold. Without it, the friction of ice would be comparable to concrete, Hache wrote. This microscopic wet layer and other physical properties of ice make a sharpened skate on ice one of the fastest non-motorized ways of propelling the human body. Though downhill skis move fast, the friction between a waxed downhill ski and snow is 10 times greater than that between a steel skate blade and ice.

Using the magical surface of ice to combat friction, hockey players are able to generate incredible amounts of energy. Hache calculated that 180-pound Colorado Avalanche forward Paul Kariya has more kinetic energy while skating at full speed than does a charging National Football League lineman of 300 pounds. He also calculated that a hockey player’s pads and flesh will compress as much as four inches during a collision with another player.

A goaltender on a series of teams since his youth, Hache devotes a chapter of his book to facts about that position. A goalie’s huge leg pads and other equipment cover 60 percent of a shooter’s target, the 4-by-6 foot goal made of red pipe and netting. Those leg pads, which cover 20 percent of the net space all by themselves, are made of leather and light synthetic padding because a hard plastic shell would allow the puck to bounce too far.

Hockey players have blasted slapshots faster than 100 miles per hour using a three-stage process, Hache wrote. First, a player rotates his torso and stick in an accelerated motion toward the puck. Next, his stick blade touches the ice and the puck as the stick bends for a fraction of a second, storing energy like a loaded spring. The puck accelerates off and the stick returns to its original shape as the player completes his swing. The puck rockets toward the goal as the player converts angular momentum (stick and torso swing) to linear momentum (the puck traveling a straight course for the goal).

Players mastering this technique include Al MacInnis of the St. Louis Blues, who won the 2003 NHL hard shot competition with a speed of 98.9 miles per hour, and the retired Al Iafrate, whose slapshot registered 105.2 miles per hour in 1993.

Source : University of Alaska Fairbanks

Huge boost to sheep genome mapping

The sheep genetics industry received a huge boost last week with the announcement that New Zealand-based livestock genetics company Ovita (a 50:50 partnership between Meat & Wool New Zealand and AgResearch) has committed $1.2 million worth of funding to help map the sheep genome.

"Just as mapping the human genome will help in fighting disease, mapping the sheep genome could help livestock producers breed better animals faster," Independent Chairman of Ovita, Rick Bettle said today.

The genome is defined as all the biological information that makes up an organism, including its genes and DNA sequences. When scientists first mapped the human genome they found that they could measure the differences in DNA between individuals.

Director of SheepGenomics, Dr Rob Forage, explained how mapping the sheep genome could benefit the sheep industry.

"In the livestock industries, we're interested in the parts of the DNA that are responsible for livestock production traits," Dr Forage said.

"Many desirable livestock traits can"t be measured early enough or on farm; for example eating quality can only be measured after growth and slaughter. By knowing which parts of the genome are responsible for particular livestock traits we could make a selection or breeding decision based on information from a DNA marker test.

"In this way the sheep genome can deliver a very powerful set of diagnostic tools on which to manage the sheep better or to breed a better next generation."

Although several years away, the DNA marker information gained from the sheep genomics program is planned to be delivered through Sheep Genetics as a �marker-enhanced' Australian sheep breeding value (ASBVme).

"Where the DNA markers impact on characteristics that are already measured or held by Sheep Genetics, such as eye muscle depth and scanning data, then we could add the genetic status of the animal from the DNA marker test to what we already know on the breeding value," Dr Forage said.

As part of a coordinated international effort, Australian researchers have been involved in sheep genome sequencing work since 2002.

In late 2003, the $30 million SheepGenomics program - a joint Meat & Livestock Australia and Australian Wool Innovation initiative - was established to translate this global research into tangible benefits for the Australian sheep industry.

The money provided by Ovita will help fund an international collaboration led by Australian scientists from the University of Sydney, AgResearch, University of Utah and CSIRO Livestock Industries called the International Sheep Genomics Consortium (ISGC). Key financial investors in the ISGC are Ovita (NZ$1.2M), the Australian Federal Government (through an International Science Linkage Grant of A$857,000), SheepGenomics (A$507,000) and Genesis Faraday (UK�100,000).

Already the ISGC has mapped a �virtual' sheep genome sequence, which was announced in November 2006 and based on the DNA information then available.

SheepGenomics continues to research many livestock traits including muscle growth, wool performance traits, resistance to parasites, and lamb survival. The advances being made have borrowed heavily from prior international investment in human and cattle genomics, allowing the Australian sheep industry to save money and shorten the research path by several years.

Dr Forage said the $1.2 million boost in funding from Ovita was a sign of how important, and how extensive, the sheep genome project is.

"This is a very good example of trans-Tasman cooperation in an area of great economic significance to both countries," Dr Forage said.

"This funding from Ovita further shores up the trans-Tasman collaboration between Meat & Wool New Zealand, AWI and MLA in the field of sheep genomics.

"It"s not just Australia and New Zealand collaborating on this project. The international science community is working together to coordinate the discovery and development of a DNA diagnostic tool that can be applied to sheep. In the process, we will get a first glimpse of a sheep genome sequence

Source : Farmnews

Space Adventures sends 2 more tourists to space

Space Adventures Ltd. has signed a contract with Russia's Federal Space Agency to fly two more people to space on the Soyuz spaceship.

Two private people have already reserved the seats and are paying $30 million each to go in 2008 and 2009. Space Adventures would not release the names yet.


The Vienna-based company has sent five people to space since it was founded in 1998, including Dennis Tito, Mark Shuttleworth, Greg Olsen, Anousheh Ansari and Charles Simonyi. Each flight includes training and more than a week orbiting the Earth aboard the International Space Station.

Space Adventures also proposed buying seats from Russia for flights in 2010 and beyond.

For those who can't afford the trip, Space Adventures offers people interested in space a membership for $980 each year to the Spaceflight Club, which gives them entry to events and a network of other space enthusiasts.

Space Adventures has an office in Moscow. Its advisory board includes Apollo 11 moonwalker Buzz Aldrin, Skylab astronaut Owen Garriott and Russian cosmonaut Yuri Usachev.

Source : BizJournals

Science of winning checkers solved

Researchers say find a key to artificial intelligence

Chinook vs Marion Tinsley in 1994

Boston Globe photo by David L. Ryan, August 15, 1994

Dr. Marion Tinsley plays checkers in a rematch against Chinook, a super computer, at the Boston Computer Museum in Boston on Aug. 15, 1994. Tinsley won his his first match-up against the computer in 1992 in London but lost the rematch after he was unable to complete round seven due to illness. The first six games had been a draw.

Now, the programmers behind Chinook have fully solved the game, creating an unbeatable program that will choose the best move in every possible situation.

'The program can achieve at least a draw against any opponent, playing either the black or white pieces,'' the researchers say in this week's online edition of the journal Science.

With its uniform pieces and simple moves, checkers may seem like a simple kid's game. But it took hundreds of computers running continuously for nearly 20 years before researchers announced today that the game has officially been solved, a major benchmark in the development of artificial intelligence.

Thirteen years ago, a program named Chinook beat the reigning human world checkers champion, a feat that preceded Deep Blue's famous chess defeat of grandmaster Gerry Kasparov by three years.

"In artificial intelligence, the chess and checkers groups have gone beyond the pale of what we thought we could do," said Michael Genesereth, an associate professor of computer science at Stanford University. "At one point, we thought we never could solve them in this way."

The team, led by University of Alberta computer science professor Jonathan Schaeffer, detailed the process Thursday on the Web site of the journal Science. The effort required up to hundreds of computers working since 1989 to analyze all possible board combinations of checkers, roughly 500 billion-billion scenarios.

"Had I known it 18 years ago it was this big of a problem, I probably would've done something else," Schaeffer said. "But once I started, I had to finish."

Beyond accomplishing absolute mastery of checkers, methods developed by Schaeffer's team in the process of solving the game may be applicable to other areas, such as business and biology. As opposed to previous "brute force" applications like Deep Blue, the program's searches save time by testing only the most relevant moves from the enormous number of possible board combinations.

"We built a huge database and had to compress it into something that was manageable, and could be accessed and searched fast by people," Schaeffer said. "That core infrastructure that we developed is generic enough for other applications."

The resulting program proves conclusively that checkers is a "draw" game; in other words, perfect play by both players will always result in a draw.

However, checkers players predict that solving the game will not affect face-to-face play.

"No human can possibly memorize the billions of combinations that Dr. Schaeffer has covered," said Richard Beckwith, player representative for the American Checkers Foundation. "You still have to play as you see it, based on your own expertise and knowledge."

Beckwith notes that the most significant impact of increasingly smart checkers programs has been to eliminate the practice of "correspondence games," where moves were sent between players by mail.

"People use programs to make moves, so you don't see people lose games any more," he said.

On Thursday, the Alberta team made the new program available to play against on the Internet at http://www.cs.ualberta.ca/~chinook.

Schaeffer, however, doesn't expect it to be a runaway hit.

"In some sense, it's not interesting," he said. "People play games for fun, and knowing you can never beat it isn't fun."

Source : Chicago Tribune & Sun Times

A genius of science to be honored

Robert Langer, a 'kid from Albany' who became MIT professor, to be honored at White House ceremony.

President Bush will bestow one of the nation's highest scientific awards on Albany native Robert Langer later this month, honoring the chemical engineer's brilliant mind, if not his clumsy hands.

Langer, a Massachusetts Institute of Technology professor, will receive the National Medal for Science at the White House on July 27. Langer's mother, Mary, who lives in Slingerlands, will be at his side.


"I won't be surprised when I hear he has won the Nobel Prize," said Robert Linhardt, a Rensselaer Polytechnic Institute professor who trained under Langer.

Langer's work explores the intersection of bioengineering and material science. He synthesized a plastic that allows large molecules of drugs to pass through and fight cancer at the site of a tumor. The breakthrough eased the side effects of chemotherapy.

He created a biodegradable microchip that can be implanted after a brain tumor is removed to slowly release cancer-killing drugs. He also developed structures that promote tissue growth, allowing doctors to grow artificial skin for burn victims.

"I always thought of myself as this kid from Albany, New York, and I feel incredibly lucky to be in the company of past and current recipients of the Medal of Science," Langer said. "It's a very remarkable group."

Langer has authored more than 1,000 scientific papers, holds more than 550 patents and has won numerous awards, including the Draper Prize, the Lemelson-MIT Prize for Invention and Innovation and the Albany Medical Center Prize.

Linhardt acknowledged Langer's brilliant mind, but warned he wasn't so good in the lab.

"I can remember him only once working himself in the lab," he said. "Everyone scattered. They were afraid he was going to set the lab on fire."

Linhardt worked as a postdoctoral student in Langer's laboratory at MIT in 1979. At the time, Langer only had three students under him. Today, he has 100 and the Langer Lab is the largest biomedical engineering lab in the world.

"He's very actively involved in his laboratory and their ideas even though he doesn't go into the lab and do the research himself," he said. "He's very good at generating ideas. He thinks in a very creative, nonlinear way and jumps from one idea to the next."

Balancing test tubes and chemicals may not be Langer's strength, but he has a gift for motivating, cajoling and cheering his researchers toward breakthroughs and an ability to think "outside the box," Linhardt said.

Judah Folkman, a doctor at Children's Hospital Boston and Langer's mentor, invited Langer to solve a problem the hospital was struggling with. Putting casts on newborns often caused blisters and pain because of the heat generated as the cast hardened. The doctors thought they needed to put more padding under the cast, but Langer said, why not address the heat?

He asked for some powdered urea, the chemical in urine, and demonstrated how it could turn a glass of warm water ice cold.

"He's an example of a real genius," Folkman said. "A genius thinks about a problem in a way the most other people wouldn't get."

Langer went further. His lab started looking at whether urea could cool a forming hurricane.

"He's a very unusual person," Linhardt said. "He takes big leaps over the rest of us. When I come up with my next idea, it's derivative, it comes from the first idea. His ideas jump big distances from the first idea and are as unconnected as a cast from a hurricane."

James Barba, president and CEO of Albany Medical Center, called Langer a national treasure.

"His ability to do tissue engineering, his ability to develop the concept of time-release medication, his ability to create synthetic skin, and I could go on and on," Barba said. "All of these things make life better for everyone. That's the definition of a treasure. He's a wonderful asset for all of us."

Barba was on the selection committee that chose Langer for the Albany Medical Center Prize. Barba boasted that Langer was born at Albany Med and has kept his ties to the area, including an appearance as commencement speaker at the Albany Medical College graduation.

Langer is a contender for the Nobel Prize, Barba said.

"If you take a look at the body of his work over the span of his career, it has been so prolific an so important that it would be hard for a committee, like the Nobel Prize committee, to overlook it," he said.

As for Langer, he said his work isn't done.

"I feel like I've accomplished something, but there's a lot more that I want to accomplish," he said.

His lab is researching ways to deliver gene therapy into cells safely, to make new tissues for organs and the spinal cord, and design microchip that can be assess the body's signals and deliver the appropriate medicine.

Helping people is his goal, but teaching the next generation of scientists, researchers and thinkers motivates him, too. About 150 of his former students have become college professors.

Langer admits his lab skills may be a little rusty. He's too busy thinking up his next idea.

Source : Times Union Albany

Science of Traffic Jams : How to Ease It


Merging-lane Traffic Jams, A Simple Cure


<<<<< ON THE LEFT: NORMAL DRIVERS WHO PACK THEMSELVES TIGHTLY TOGETHER WHENEVER THE TRAFFIC COMES TO A STOP. NOBODY CAN MERGE EXCEPT AT THE END OF THE JAM. NOTE THEIR LOW SPEED.


ON THE RIGHT >>>>> DRIVERS WITH UNUSUAL BEHAVIOR: THEY ENCOURAGE OTHERS TO MERGE AHEAD OF THEM, AND THEY TEND TO MAINTAIN LARGE SPACES AHEAD, EVEN IF TRAFFIC SLOWS TO A CRAWL. MERGING IS EASY. SEE HOW MUCH FASTER THEY GO?


Traffic jams often occur on highways wherever two lanes must merge into one. Lanes of cars cannot merge if there are no large gaps between cars. Therefor, drivers who create large gaps between cars will ease this type of traffic jam.

To ease this type of jam:

  • Maintain a large space ahead of your car.
  • Encourage one, two even three cars to merge ahead of you.
  • If traffic slows to a complete stop, KEEP TWO CAR-LENGTHS OF SPACE OPEN AHEAD OF YOU.
  • Never "punish" merging drivers by closing your gap.

Amazingly enough, it is not necessary that EVERYONE do this. If only a few drivers will maintain large gaps during heavy traffic, then merging traffic is not forbidden, and the situation in the left-hand diagram can be prevented.

Yes you're right, you cannot eliminate every problem by simply making a big gap in front of your car. When there are too many cars on the road, traffic slows down. But if we use these special driving habits, the smaller jams can be erased, and stop-and-go traffic can be smoothed out. Since many traffic jams are caused by merging lanes, many traffic jams can be improved by the actions of just one driver.

Source : SmartMotorist

Say goodbye to the traditional bubble spacesuit

A team at the Massachusetts Institute of Technology (MIT) have designed a sleek skin-tight spacesuit which is a giant leap in space garment design.

Current spacesuits have changed very little in the past 40 years. The bulky, gas-pressurised outfits do give astronauts a bubble of protection, but their significant mass, and the pressure itself, severely limits mobility.

Dava Newman, a professor of aeronautics and astronautics and engineering systems at MIT, wants to change that.

Newman is working on a sleek, advanced suit designed to allow superior mobility when humans eventually reach Mars or return to the Moon.

The spandex and nylon creation is more Judy Jetson than Neil Armstrong.

Traditional bulky spacesuits "do not afford the mobility and locomotion capability that astronauts need for partial gravity exploration missions", Newman said.

"We really must design for greater mobility and enhanced human and robotic capability," she added.

Seven-year project based on 40-year-old ideas

Newman, her colleague Jeff Hoffman, her students and a local design firm, Trotti and Associates, have been working on the project for about seven years.

Their prototypes are not yet ready for space travel, but demonstrate what they're trying to achieve - a lightweight, skin-tight suit that will allow astronauts to become truly mobile lunar and Mars explorers.

Newman anticipates that the BioSuit could be ready by the time humans are ready to launch an expedition to Mars, possibly in about 10 years.

Current spacesuits could not handle the challenges of such an exploratory mission, Newman said.

The suits could also help astronauts stay fit during the six-month journey to Mars.

Studies have shown that astronauts lose up to 40 per cent of their muscle strength in space, but the new outfits could be designed to offer varying resistance levels, allowing the astronauts to exercise against the suits during a long flight to Mars.

Although getting the suits into space is the ultimate goal, Newman is also focusing on Earth-bound applications in the short term, such as athletic training or helping people walk.

The new BioSuit builds on ideas developed in the 1960s and 1970s by Paul Webb, who first came up with the concept for a 'space activity suit', and Saul Iberall, who postulated the lines of non-extension.

However, neither the technology nor the materials were available then.

The project was initially funded by the NASA Institute for Advanced Concepts.

Japan quake and radioactive leak spur concerns about reactor safety

A fire and leaks of radioactivity from the world's largest nuclear power plant in an earthquake in Japan have prompted the government to reassess safety standards at the temblor-prone country's atomic reactors. The operators of the Kashiwazaki Kariwa plant, the world's biggest in terms of power output capacity, were quick to arguethat the accidents in Monday's killer quake posed no threat to the environment. But the mishaps illustrated the weak points in Japan's nuclear plants, an accident-plagued network that provides a third of the country's electricity. The government had already been working on raising quake resistance standards at Japan's 55 reactors. Since the quake, plant operator Tokyo Electric Power Co. has acknowledged a leak of radioactive water, accidental emission of radioactive cobalt-60 and chromium-51 from an exhaust stack, and the tipping over of barrels of low-level nuclear waste. It was not clear if any of the waste spilled. Only hours after the water leak was announced late Monday by TEPCO, the trade minister ordered the company not to restart the plant without a thorough review of safety measures, and called for similar measures at other reactors. «It will not resume operations until we ascertain its earthquake-proof structure,» Economy, Trade and Industry Minister Akira Amari said Tuesday, adding he had ordered other operators to provide emergency response plans. The problems at the plant in Kashiwazaki on Monday at first appeared minor. The 6.8-magnitude quake ripped into the coastal region in midmorning Monday, triggering the plant's automatic shutdown system. A small fire broke out at an electrical transformer at a reactor, but the blaze had been put out by early afternoon. TEPCO said there was no damage to the reactor. But some 12 hours after the quake, the company publicly announced that some 1,200 liters of water containing radioactive material had leaked from a reactor building in the quake and was flushed into the sea. TEPCO officials said the amount of radioactivity was far below Japanese safety standards and would have no environmental impact. But the leak _ and the time it took for the company to announce it _ raised alarm bells. The leak was discovered at about noon on Monday, but TEPCO said it took till 6:20 p.m. to confirm it contained radioactivity. The company notified the government at 7:10 p.m., and announced it to the public at 9:45 p.m. «Their report was late, and they were also behind in putting out the fire,» said State Minister Sanae Takaichi, whose portfolio includes science and technology. «It is important that they thoroughly investigate the cause. The tipping over of the waste barrels was announced on Tuesday. The emission from the exhaust stack was also announced on Tuesday, though officials said they did not know when it started or whether it was related to the quake. Currently, government standards require plants to be built to withstand magnitude-6.5 quakes, but a review of that was launched last September with the aim of increasing resistance up to a 6.9 quake, said Masanori Hamada, professor on earthquake engineering at Tokyo's Waseda University. Hamada said that in light of the Niigata quake, the government should set the bar higher. «With close examination of data on the latest tremor, we will have to increase the quake-resistance standards for nuclear power plants to meet the new situation,» Hamada said, adding that the fire and leak were the result of «lax management. Environmentalists warned that such disasters could lead to much worse releases of radioactivity. «There is a real risk in Japan, and globally, of larger earthquakes and other natural disasters, as well as of terrorist attacks that could lead to far more serious nuclear accidents,» Jan Beranek, Greenpeace International Nuclear Campaigner, said in a statement. Japan's record in nuclear safety is not a happy one. The country, spurred by lack of domestic fossil fuels and concerns over global warming, is working on increasing its reliance on nuclear power to 40 percent of its electricity supply by 2010. But the industry has been dogged by accidents and cover-up scandals, and public trust runs low. In August 2004, five workers at the Mihama Nuclear Power Plant in western Japan were killed and six others were injured after a corroded pipe ruptured and sprayed plant workers with boiling water and steam. The accident was the nation's worst at a nuclear facility. In 1999, an accident at a nuclear reprocessing plant north of Tokyo killed two workers and exposed hundreds to radioactivity. Associated Press writers Kozo Mizoguchi, Carl Freire and Chisaki Watanabe contributed to this report.

Source : AP News

World's first cloned rabbit has survived for 5 months

The world's first cloned rabbit, produced with the body cells of an embryonic rabbit, passed a molecular biology test, on July 10, at the Chinese Academy of Agricultural Sciences. Born on February 12, 2007, the cloned rabbit has survived for 5 months.

The cloning experiment, conducted by Li Shangang, a PhD at the National Center for Molecular Genetics and Breeding of Animals at the Institute of Veterinary Sciences, selected the posterior skin cells of a 20-day old rabbit embryo.

After acquiring the fibroblast cell, Li used this type of cell as the donor cell; and injected it into a rabbit's oocyte that had been applied by a nucleation method with electric devices. Finally, the scientist transferred the modified cell into the parent rabbit's fallopian tube.

Source : China Daily Science

Heavy school bags may cause chronic backaches

Math, English, SST, Science, Practical file, French, Moral Science, GK, homework copy -- that's how many books a seven year old carries to school every day in New Delhi. The number of books is 14, just double their age.

And if your child is rushing to school every morning, slinging that heavy back pack over a shoulder, a word of caution, for studies show that 60 per cent of children get backaches, as a result.

And the books just get heavier.

Says Physiotherapist Max Healthcare, Dr Alakananda Banerjee, "Studies have shown that children who carry backpacks that weigh more than 20-25 per cent of their body weight are more likely to develop backaches. And at that age a child's spine is growing and is tender."

What's worse is that a heavy backpack also leads to bad posture. In the long run, your child might develop abnormal curves and spinal deformities and unfriendly ergonomics at school just add to it.

"Why this is very harmful is that this goes on for years, till the time the child is out of school. By then, the posture is already affected," says Dr Banerjee.

So, what is the ideal weight a child should be carrying? Experts say, no more than 15 per cent of his or her body weight.

And some schools have woken up to the alarming health repurcussions and are doing their bit by providing lockers, ergonomic chairs and tables, and even planning better timetables.

Says Principal Kothari International School, Seema Sapru, "The Supreme Court had enforced the Children School Bags Bill last year, which says that the weight of the school bag should not exceed ten per cent of the child's body weight and toddlers must not carry school bags at all!"

However, until schools follow up on this, one could help by buying children the right back pack -- one with padded shoulder straps, that fit snugly onto the middle of the back. And make sure the weight's distributed evenly across both shoulders.

Source : IBN Indian News

Water found on planet outside Solar System

Water has been discovered on a planet outside our solar system for the first time - giving scientists a tantalising hint of life existing beyond the Earth.

The planet, known as HD189733b, is a Jupiter like gas giant which is about 60 light years away in the constellation of Vulpeca the Fox.

Giovanna Tinetti, a European Space Agency fellow at the Institut d'Astrophysique de Paris in France who led the study said ''We're thrilled to have identified clear signs of water on a planet that is trillions of miles away''.

HD 189733b is known as a ''hot Jupiter'' planet -- like the solar system's gas planet. It is similar to Jupiter but far hotter.

Researchers have observed that absorption by water vapour is the most likely cause of the wavelength-dependent variations in the effective radius of the planet at the infrared wavelengths.

Astronomer Heather Knutson of Harvard University said that the findings contradicted the earlier studies showing no evidence of water.Knutson reviewed the findings in the same issue of Nature.

Knutson also mentioned that however, the earlier studies looked at light emitted from the day side of the planet while the latest research used a different method that measured light transmitted through the outer edges of the planet's atmosphere.

She said that this suggested there might be something hiding a water signal in the previous measurements.

''In the long term we could evaluate other planets that could support life and have water in their atmosphere,'' Knutson said.

Source: DDNEWS India

Can Hair Turn White from Fright?

For centuries there have been reports of people who suddenly have hair turn white from fright or from tremendously stressful circumstances. According to many accounts, Marie Antoinette had her hair turn white the night before she was executed. Although this makes for a more dramatic story, evidence suggests Marie Antoinette's hair turned white far prior to this, and the process was not sudden.

The trouble with all accounts of people suddenly experiencing their hair turn white is that it’s not possible. White or gray hair begins at the hair shaft, so hair on your head is already dead material. It can’t suddenly change color, unless you visit a local beauty salon. Newly white hair must grow from the roots out, at the rate of typical hair growth, making the overnight process of having one’s hair turn white from fright an unlikely scenario.

Still, there are many who insist that people have had their hair turn white in an overnight situation of extreme stress. It is possible for it to appear as though a person suddenly woke up with white hair. This process requires that the person already have large amounts of white or gray hair before the change.

What can happen to hair in highly stressful circumstances is that some hair might fall out, in a condition called diffuse alopecia areata. This condition results in significant hair loss and occurs rapidly. In these instances, hair that is not colored could fall out, while a moiety of white hair or grey hair remains. This would give the appearance that one had their hair turn white overnight. In fact, what really occurred is someone lost a great deal of colored hair in a short period of time.

Alopecia areata tends not to occur overnight, but can occur suddenly. It tends to be linked to autoimmune disease where the cells in the body suddenly view the hair cells as foreign matter and attack them.

The result can be patches of baldness on the head, and in worst cases, all over the body. Normally alopecia areata is treated with medications like prednisone, which allows the body to shut down its immune response. Treatments with prednisone was unavailable until the 20th century, perhaps accounting for more "white overnight" stories earlier.

It’s unclear what triggers alopecia areata, but it can occur in men, women and children. In people with an abundance of gray hair, this could cause one to appear as though the hair had suddenly turned white. It would also result in patchy baldness, so the hair would appear thin. Other causes of sudden baldness include bad cases of ringworm, not terribly uncommon in previous centuries, or severe hyperthyroidism, which can cause sudden and significant hair loss.

Accounts of those who have their hair turn white suddenly are essentially urban legends. It’s more reasonable to say that if hair suddenly appeared white, it was due to significant loss of colored hair.

Source : JECS Health Journal

When Bubble Meets Bubble

When one bubble meets with another, the resulting union is always one of total sharing and compromise (Human beings could learn a lot from bubbles.) Since bubbles always try to minimize surface area two bubbles will merge to share a common wall. If the bubbles are the same size as the bubbles to the left, this wall will be flat. If the bubbles are different sized, the smaller bubble, which always has a higher internal pressure, will bulge into the larger bubble.

Regardless of their relative sizes, the bubbles will meet the common wall at an angle of 120 degrees. This is easy to see in the bubble picture to the right. All three bubbles meet at the center at an angle of 120 degrees. Although the mathematics to prove this are beyond the scope of this article, the 120 degree rule always holds, even with complex bubble collections like a foam.


If you take two sheets of clear glass or plastic seperated by about one-half inch, soak them in soapy solution and then blow bubbles between the sheets, you will get many bubble walls. If you look closely, you will notice that all of the vertices where three bubble walls meet (and there are always three,) form 120 degree angles. If your bubbles are of uniform size, you will notice that the cells form hexagons and start to look much like the cells of a beehive. Bees, like bubbles, try to be as efficient as possible when making the comb. They want to use the minimum possible amount of wax to get the job done. Hexagonal cells are the ticket.

Check the following interesting site too. He makes bubbles alive!

Excerpt :
.... Before first bringing his performance to television in the early 80s, Tom Noddy spent over a decade developing a new kind of performance piece. Sitting alone with dime store bubble solution, a childlike sense of wonder and an adult sense of humor he brought a new thing into being: Bubble Magic.

Bubble Magic with Tom Noddy!

Additive used in sausages and burgers may cause cancer

An E number used to make commercial sausages and burgers pink may cause cancer. Scientific studies suggest Red 2G, or E128, causes tumours in rats and mice and might have the same effect on people.

After reviewing the experiments, the European Food Safety Agency (Efsa) said it could set no safe limit for the additive.

The European Commission is expected to ban its use within a fortnight, but products containing the additive on the shelves are not likely to be withdrawn.

Efsa has been reviewing the safety of colourings, many of which were approved for use 30 years ago. In a statement yesterday, the agency said its scientific panel on food additives, flavourings, processing aids and materials had reviewed several evaluations of Red 2G since 1999. It found the E number, one of a band of controversial "azo-dye" colourings, converted in the body into a substance called aniline.

"Based on animal studies the panel concluded that aniline should be considered as a carcinogen," Efsa said, adding that it was not possible to state that the cancer had developed because of the genetic structure of the animal cells.

"It is therefore not possible to determine a level of intake for aniline which may be regarded as safe for humans," it added. "The panel therefore decided that Red 2G should be regarded as being of safety concern."

The European Commission is "reflecting" on the assessment and is expected to act at a meeting with member states on 20 July. A spokesman said Red G was used in Britain and Ireland but was not used in Scandinavia.

Yesterday it was found that several British companies selling sausages and burgers with Red 2G on the internet. Many supermarket products are unlikely to contain it, however, because many chains have been removing E numbers amid public concern at the effect of additives.

Ian Tokelove, of the pressure group the Food Commission, said there had been concerns about Red 2G going back decades and it was suspected of being a carcinogen in the 1980s. "Our general view is that additives are totally unnecessary," he added. "We don't need them in our food. They're there to disguise the quality of the food and in this case to make meat products look fresher and meatier than they are."

Red 2G is permitted for use in breakfast sausages with a minimum cereal content of 6 per cent and in burgers with 4 per cent of vegetables or cereals. It gives meat a reddish-pink appearance that turns brown on contact with heat.

Source : Belfast Telegraph

New toothpaste can regrow teeth

The $3 billion global market for toothpaste is on the verge of a shake-up as new biotechnologies come through that not only curtail sensitivity problems but will also enable teeth to re-grow to fill in small cavities. Today’s toothpaste comes in a plethora of flavours and can of course whiten teeth but from a medical viewpoint, little has progressed in the 40 years since fluoride was added to fight decay.
Now though scientists in various countries have developed differing technologies that produce similar results to deaden sensitivity and recalcify the teeth, problems that have increasing significance as populations age. Researchers have found fluoride ceases to be as effective with older people. That’s because the elderly have more difficulty generating the large amounts of saliva – loaded with calcium and phosphate - necessary to combine with fluoride to resist the demineralisation of teeth. Also, said Richard Bernholt, managing director of west London-based dental care company Periproducts: “The older you are the more likely you are to have gums receding and sensitivity problems because of what you eat.”
Periproducts, which sells Retardex products in the UK, has licensed NovaMin technology from a Florida firm of the same name and hopes to be the first company to have it formulated in a retail brand in the UK later this year. Periproducts plans to launch its new toothpaste in October at the British Dental Trade Association exhibition at NEC Birmingham. The company wants to get its as-yet-unnamed toothpaste with dentists and into the retail chain before the big names in oral hygiene – Colgate-Palmolive, GlaxoSmithKline, Johnson & Johnson, Unilever and Procter & Gamble reformulate their products with NovaMin or competing calcium phosphate compounds.

Source : Bahrain Tribune

Science Forgeries and Frauds

Greed for money and fame. Here are just a few.

Paluxy FootprintsYear: 1939 Originally appeared in: "Thunder in his Footsteps" by Roland T. Bird in Natural History Now appears in: "History of Science: Fossil Proboscidians and Myths of Giant Men" by James L. Hayward in Transactions of the Nebraska Academy of Sciences (Also discussed in Quest for the African Dinosaurs by Louis Jacobs) The worst thing about this hoax is how many people still fall for it. In the 1930s, American Museum paleontologist Roland T. Bird paid a visit to the Paluxy River limestone beds near Glen Rose, Texas, to see a spectacular dinosaur trackway. Bird's visit came during the Depression, and some locals decided to sell tracks from the region in hopes of making some much needed cash. They quickly figured out it would be easier to carve footprints than dig up the real things, and that it would be more interesting to carve giant human footprints than dinosaur tracks. A fraud is a glowing success when it tells people what they want to believe, and many biblical literalists embraced this so-called evidence that humans and dinosaurs coexisted. Truth is, we missed each other by about 65 million years.



Sea SerpentYear: 1845 Con artist: "Dr." Albert Koch Originally published in: Hydrarchos Now appears in: Monsters of the Sea by Richard Ellis This illustration accompanied Albert Koch's description of a "gigantic fossil reptile" 114 feet long. In truth, Koch pieced together the bones of five fossil whales, then showed the specimen in the U.S. and in England. The hoax was exposed on both sides of the Atlantic.


Composite fossilYear: 1997 Con artist: Unidentified Chinese fossil collector (who might not have known he was defrauding anyone) Originally published in: National Geographic Magazine, November, 1999 issue For more information: National Geographic Magazine, October, 2000 issue (Photo by O. Louis Mazzatenta), Nature Magazine, February 17, 2000 issue, Unearthing the Dragon by Norell and Ellison In 1997, a Chinese farmer found an exquisite birdlike fossil with faint feather impressions. A couple yards away, he found a lizardlike fossil tail. He took these and other finds home, glued the pieces together, then sold the result to a local dealer. To the farmer, it looked like a nice, complete fossil, which would bring him a little more money than shattered pieces. To less-than-careful eyes, the composite looked like a missing link between dinosaurs and birds. Over the next two years, the composite fossil made its way into the hands of a loose association of amateur dinosaur enthusiasts, professional paleontologists and National Geographic editors. With unprecedented achievement in lousy communication, various members of this group purchased the fossil for $80,000, insured it for $1.6 million, proudly announced the new species Archaeoraptor liaoningensis, then eventually wished they'd never seen the little fossil. Added to the embarrassment was the near certainty that it had been illegally smuggled out of China, a fact which — to its credit — National Geographic insisted be remedied before it agreed to publish the find. (The fossil was eventually repatriated.) The original plan was to describe the fossil in a peer-reviewed publication — a contingency that National Geographic gambled on — but after the paper was rejected by both Nature and Science, National Geographic didn't have time to pull the article. The magazine ignored its policy of awaiting publication in a peer-reviewed paper and announced the find. Just a few months later, Xu Xing, a collaborator in the research announced the bad news, and confirmed what a few others had quietly suspected: The fossil was a composite. In fact, it was a composite of 88 pieces. Finger pointing ensued. Creationists loved it. But as paleontologist Mark Norell has pointed out, the fossil never passed peer review, and the scientists involved revealed the forgery.


MermaidYear: 1842 Con artist: P.T. Barnum Originally published in: New York Herald Now appears in: Monsters of the Sea by Richard Ellis (Also discussed in The Feejee Mermaid by Jan Bondeson) P.T. Barnum's skillful manipulation convinced thousands to see his "Feejee Mermaid." It was displayed for "positively one week only!" at a concert hall on Broadway. Years later, Barnum recounted with amusement how he had lured the crowds to see an "ugly, dried-up, black-looking specimen about three feet long . . . that looked like it had died in great agony." A generation earlier, on the other side of the Atlantic, the mermaid enjoyed similar notoriety. An American captain named Samuel Barrett Eades purchased the mermaid in 1822, paying for the prize by selling the ship he was supposed to sail. The ship's real owner, Stephen Ellery, was hardly amused. Ellery hired William Clift, a talented anatomist and zoologist, to examine the specimen. Clift found the mermaid was a skillful forgery incorporating the head on an orangutan, the teeth of a baboon, artificial eyes, and likely the tail of a salmon. Eades didn't welcome this news, and later hired his own "experts" to assure him the mermaid was genuine. After entertaining crowds of Londoners, the mermaid fell into obscurity for two decades before Barnum bought it.


SnakesNow appears in: Fossils: Evidence of Vanished Worlds by Yvette Gayrard-Valy and The Floating Egg by Roger Osborne For many years, the ground in the village of Whitby, England was strewn with baffling objects vaguely resembling coiled snakes. Local legend explained that years earlier, the area was crawling with snakes which St. Hilda (Abbess of the Whitby Abbey) beheaded and turned to stone. This coat of arms of the town of Whitby recalls that legend. In less benign tributes to the legend, locals "found" the original snake heads and reattached them to the snakes, then (not surprisingly) sold them. In fact, the heads were skillfully carved from stone. And the snakes? They are really fossil ammonites that went extinct at the same time as the dinosaurs
.

Fake FossilsYear: 1726 Con artists: J. Ignatz Roderick and Georg von Eckhart Originally published in: Lithographiae Wirceburgensis Now appears in: The Lying Stones of Marrakech by Stephen Jay Gould In the early 18th century, Johann Bartholomew Adam Beringer, a professor and physician from Wu"rzburg, published a book documenting "fossil" finds from a nearby mountain. His finds included everything from spiders on their webs to lizards with their skins intact. Legend has it that Beringer was the object of a joke by his students, but he was actually defrauded by two of his colleagues. When Roderick and Eckhart learned that Beringer intended to publish his finds, they nervously warned him that the fossils were fake, but by then Beringer was a man with a purpose. Although Beringer mistakenly assumed the fossils were natural, not carved, he refused to speculate any further, instead publishing his finds for others to analyze. Based on today's understanding of fossils, Beringer's mistake seems remarkably stupid. In his time, however, the process of fossilization was poorly — if at all — understood. Whether fossils were organic in nature or the results of the same forces that made rocks themselves was not yet known.


PiltdownYear: 1911 Originally appeared in: Several hundred publications Now appears in: Human Origins: The Search for Our Beginnings by Herbert Thomas (Discussed in detail in The Piltdown Forgery by J.S. Weiner) Perhaps the best known case of scientific fraud, the Piltdown Man was believed to be the earliest-known human from Western Europe. In fact, it was the jaw of an ape (with filed teeth) paired with a human skull. Amateur archaeologist Charles Dawson collected a skull fragment in 1911, and claimed that workmen digging in the gravel pit where the fragment was found had given him another piece years earlier. More excavations turned up more material. Skeptics who suspected that the skull and jaw came from two different animals were flummoxed at the 1915 find of a second individual (Piltdown II) two miles away. Many (planted) animal fossils from the area corroborated Piltdown Man, the most ridiculous being a "bone tool" that proved to be a cricket bat. And yet the Piltdown forgery was far from amateurish; the perpetrator(s) understood human and ape anatomy, fossils of "contemporary" fauna, and even the gravel beds where the fossils were collected. It wasn't until 1953 that three scientists (Sir Wilfrid Le Gros Clark, Kenneth Oakley and Joseph Weiner) uncovered the hoax. Even now, the perpetrator is unknown. Besides Dawson, suspects include English anatomist Sir Arthur Keith and British Museum employee Martin Hinton. Some speculation has even fingered Sir Arthur Conan Doyle of Sherlock Holmes fame. Exposure of the Piltdown fraud helped pave the way for acceptance of genuine hominid fossils, such as Raymond Dart's Australopithecus africanus, whose implications (evolution of bipedalism before big brains) had been "disproven" by Piltdown.


Dragon from RayYear: 1613 Scientist/artist: Ulisse Aldrovandi Originally published in: De Piscibus Now appears in: Merchants and Marvels edited by Smith and Findlen In his posthumously published book on fish, Aldrovandi didn't carry out a hoax, but instead showed how it could be done. This illustration showed a ray cleverly modified to look like a dragon. In fact, some collectors actually prized creations like this, even when they were known to be forgeries.


SkvaderYears: 1874-1918 Con artists: Ha*kan Dahlmark, Halvar Friesendahl, Carl Erik Hammarberg and Rudolf Granberg Now appears in: The Historical Preservation Society in Medelpad This cross between a female hare and a wood grouse cock was allegedly shot by Dahlmark in 1874. On his birthday in 1907, Dahlmark's housekeeper asked her nephew, Friesendahl, to paint a picture of it. Before his death, Dahlmark donated the painting to the historical society. Inspired to create a "real" skvader, the society's new director, Hammarberg, contacted Granberg, a talented taxidermist, and Granberg obliged him by making a stuffed specimen. In 1918, Hammarberg wrote an article in the local newspaper about the rare skvader, which, thanks to the sale of 3,000 postcards, would soon develop a worldwide reputation. Although some visitors to the historical society's museum are disappointed to find the skvader isn't genuine, few people have taken it very seriously.

Source : iScience Journal


Candle Burn in Micro Gravity?

Unexpected spiral-shaped flames on Earth. By studying these peculiar flames, researchers hope to mitigate fire hazards on spacecraft and gain new insights about complex systems in nature.

The forms of flames on Earth are familiar to everyone. We all know what a burning match, candle, fireplace or blowtorch look like -- or a burning building, or rocket ignition blast. The presence of gravity and the effects of air or gas movement, plus the type of fuel and oxidant, determine everything from a flame's shape and temperature to burn rate, burn pattern, soot production and deposition and how fast it will or won't be extinguished.

"But in the microgravity of space, we are not dealing with just another old familiar flame," says Dr. Vedha Nayagam of NASA's National Center for Microgravity Research on Fluids and Combustion at the Glenn Research Center (GRC) in Cleveland, OH, where the nature of combustion in space is being studied intently by teams of scientists.

Above
: On Earth, gravity-driven buoyant convection causes a candle flame to be teardrop-shaped (A) and carries soot to the flame's tip, making it yellow. In microgravity, where convective flows are absent, the flame is spherical, soot-free, and blue (B).


"The tall spear-shaped flame on a candle, or the "roaring hearth" look of bonfire-type flames, or the forced-air look of a rocket or furnace flame are very different indeed in the absence of gravity," Dr. Nayagam states. "Soot production, burning rates, completeness of combustion, exhaust products and other characteristics all change radically in space.

"The absence of gravity's effects on convection aboard the Space Shuttle, a space station or other space vehicle makes flames behave in ways that can be either beneficial -- as a test bed for research -- or very dangerous in the case of a fire in materials, chemicals or electrical devices. It is vital to know what makes flames start and stop in low gravity, and how flames behave while burning. The safety of NASA's space crews and vehicles can depend on our knowledge of combustion in space."

Watching the Flame Go 'Round

Recently, Dr. Nayagam and Dr. Forman Williams of the University of California at San Diego, a co-investigator in NASA/GRC's microgravity combustion science program, came upon some startling discoveries about flames on Earth that could help scientists understand how flames behave in microgravity.

Nayagam and Williams ignited a plastic disk a little bigger than a CD
with a blowtorch and then spun it slowly (2 to 20 revolutions per second) in still air. They expected to see flames burning as a horizontal disk. Instead, the flame burned in a flat spiral pattern, with the spiral moving in the direction opposite to the disk's spin. As the flames lessened their tips exhibited a strange meandering motion from side to side.

Right: Flames on top of a disk slowly spinning in a clockwise direction burn in a spiral headed counterclockwise. Vedha Nayagam and Forman Williams are studying this phenomenon, which occurs both on Earth and in microgravity, in the hopes of fully explaining the pattern with basic physics principles.

Starting a fire at the center of a still disk is like dropping a stone in a quiet pond, says Nayagam. It produces a flame front that moves outward in a circle, fading as the fuel (the disk) is consumed. If you spin the disk, then the circular disk flames become spiral flames under some conditions.

"Under slow spin conditions ... just before circular flames extinguish, [the flames] break symmetry -- and spirals appear in the center hole of the flames and propagate outwards in a spiral instead of in a circular wave front," he explained.

"Spiral burning could be common in the slow, swirling flows that we can establish in a microgravity environment -- but these results were very unexpected in normal Earth gravity," added Dr. Williams. "We plan to explore further what causes the spiral flame pattern, and what causes the tips to follow a [chaotic] meandering path."

Left : At NASA's Johnson Space Center, there is a microgravity research aircraft used to fly parabolas to investigate the effects of "zero" gravity. The KC-135, typically used by the USAF for aerial refueling, is the military version of the venerable Boeing 707airliner.

Nayagam says it's an advantage to be able to generate these flames in the lab under normal gravity, where it is easier and less expensive to study them than on the Space Shuttle. The investigators plan to conduct further tests with spiral flames on board the Johnson Space Flight Center's KC-135, which can create brief microgravity conditions in parabolic flight.

Why Set A Spinning Disk On Fire?

"We need to discover how and why flames propagate in microgravity, and under what conditions flame propagation changes. Hopefully the studies will also explain turbulent combustion, as the swirling flow is vital to understanding the phenomenon called fire whorl," says Dr. Nayagam.

"Understanding these surprising phenomenon may enable scientists to predict flame extinction and to help mitigate fire risks on Earth and in microgravity," states Dr. Nayagam. "The initial and on-going basic reason for NASA's combustion studies is to learn about spacecraft fire safety. We need to answer questions such as: what is the worst condition for fire in a microgravity environment, and under what conditions a fire will increase its burn rate or be extinguished. Our goals include learning under what conditions materials in a spacecraft will or won't support fire."

"The bottom line," Dr. Nayagam says, "is that this simple system of flames on a spinning disk under variable controlled conditions illustrates more complex systems on Earth, in spacecraft, and in the human body."

Source : Nasa Science Journal - 2000

Scientists crack lost lake mystery

Chilean scientists have confirmed suspicions that the missing lake which went awol in the Magallanes region of Patagonia simply drained away though a crack, Reuters reports.

The lake, when last seen back in March, boasted a surface area of around four to five hectares (10-12 acres or around 10 soccer pitches). When a team from Chile's National Forestry Corporation CONAF paid a visit in May they were surprised to find it had "completely disappeared".

The truth has now been revealed. Scientists yesterday told Chilean media that "a build-up of water opened a crack in an ice wall along one side of the lake", and the contents then "flowed through the crack into a nearby fjord and from there into the sea, leaving behind a dry lake-bed littered with icebergs".

Glacier expert Andres Rivera, who visited the site as part of a "missing lakes" investigative team, happily reported: "It looks like it's slowly filling up with water again." He did, however, offer the traditional warning that the lake's escape was "evidence of the effects of global warming".

Source : theregister.co.uk

Global Warming Map Animation

NASA has produced an animated map that illustrates changes in global temperatures between meteorological years 1891 and 2006. This animated map is an .mp4 file that can be viewed using a QuickTime player. Each frame in the animation represents a one year increment of the ten year mean temperature anomaly. This animation begins with a historic ten year (1891-1900) mean meteorological year temperature anomaly map and ends with a recent (1997-2006) ten year mean meteorological year temperature anomaly map. The animation clearly illustrates a global warming trend over the time interval.


First Frame of the Global Warming Map Animation by NASA



Last Frame of the Global Warming Map Animation by NASA


You can view the animation or read details at the NASA website.

Strange Orbits

Like toy cars chasing each other on a looped racetrack, three stars can, in principle, trace out a figure-eight orbit in space. This surprising pattern of motion arises from the force of gravity acting on three bodies of equal mass. The movements are timed so that each body in turn passes between the other two. Moreover, such coordinated movements aren't the only intricate maneuvers possible when several bodies attract one another gravitationally.

Newton's laws provide a precise answer to the problem of determining the motion of two bodies under the influence of gravity. If the solar system consisted of the sun and a single planet, for example, the planet would follow an elliptical orbit. When the system consists of more than two bodies, solving the relevant equations of motion gets very tricky.

For three interacting bodies (described as the three-body problem), mathematicians have found a small number of special cases in which the orbits of the three masses are periodic. In 1765, Leonhard Euler (1707–1783) discovered an example in which three masses start in a line and rotate so that they stay in line. Such a set of orbits is unstable, however, and it would not be found anywhere in the solar system.

Three gravitationally interacting bodies of equal mass: Euler configuration (left) and Lagrange configuration (right).

In 1772, J.L. Lagrange (1736–1813) identified a periodic orbit in which three masses are at the corners of an equilateral triangle. In this case, each mass moves in an ellipse in such a way that the triangle formed by the three masses always remains equilateral. A so-called Trojan asteroid, which forms a triangle with Jupiter and the sun, moves according to such a scheme.

Subsequent work by Henri Poincaré (1854–1912) and others demonstrated that, in general, it's impossible to obtain a general solution, expressed as an explicit formula, to the three-body problem. In other words, given three bodies in a random configuration, the resulting motion nearly always turns out to be chaotic. No one can predict precisely what paths those bodies would follow.

In 1993, Cris Moore, now at the University of New Mexico, added to the sparse list of exceptions. He discovered, via computer calculations, that three equal masses can chase each other around the same figure-eight curve in the plane.

In 2000, mathematicians Richard Montgomery of the University of California, Santa Cruz and Alain Chenciner of the Université Paris VII-Denis Diderot rediscovered the figure-eight orbit found by Moore, working out an exact solution to the equations of motion for three gravitationally interacting bodies. Montgomery described the discovery in the May 2001 Notices of the American Mathematical Society.

Three equal masses (red, blue, and green), shown at five equal time intervals, chase each other around a figure-eight-shaped curve. Initially, the three masses are in a straight line.
Courtesy of Michael Nauenberg

Computer simulations by Carlès Simò of the University of Barcelona demonstrated that the figure-eight orbit is stable. The orbit persists even when the three masses aren't precisely the same, and it can survive a tiny disturbance without serious disruption.

"What stability means physically is that there is some chance that the [figure-eight orbit] might actually be seen in some stellar system," Montgomery noted.

The chance that such a three-body system exists somewhere in the universe, however, is very small. Numerical experiments suggest that the probability is somewhere between one per galaxy and one per universe. Nonetheless, advanced imaging techniques and the recent discovery of unusual extrasolar planetary systems are providing new space-time venues in which such motions could occur.

The existence of the three-body, figure-eight orbit prompted mathematicians to look for similar orbits involving four or more masses. Joseph Gerver of Rutgers University, for instance, found one set in which four bodies stay at the corners of a parallelogram at every instant, while each body follows a curve that looks like a figure-eight with an extra twist.

Using computers, Simò found hundreds of exact solutions for the case of n equal masses traveling a fixed planar curve. "They are not stable, except for the original figure-eight case," Montgomery noted. Nonetheless, "they make beautiful patterns: flowers, chains, and so on." For examples, see http://www.soe.ucsc.edu/~charlie/3body/.

In the latest development, Moore and Michael Nauenberg of the University of California, Santa Cruz have unveiled a slew of new, periodic n-body orbits. Whereas previously discovered orbits were confined to the plane, the new orbits are three-dimensional. For a glimpse of these orbits, see http://www.santafe.edu/~moore/gallery.html.

One striking example (below) has 12 equal masses following four, roughly circular, interlocked orbits. Topologically, these orbits form the edges of a cuboctahedron.


Moore

Nauenberg gives additional examples of these three-dimensional orbits at http://physics.ucsc.edu/~michael/ (see section on recent publications). Even in the case of three bodies, it's possible to have intriguing nonplanar, figure-eight orbits.

Somewhere in the universe, triple stars and weird planetary systems may be doing crazy eights—and more! It would certainly be heavenly choreography.

Source : ScienceNews Journal

 
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