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| ©Institute of Physics |
| Acoustic cloak. |
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Researchers in Spain have proven that metamaterials, materials defined by their unusual man-made cellular structure, can be designed to produce an acoustic cloak -- a cloak that can make objects impervious to sound waves, literally diverting sound waves around an object.
Using a convenient and flexible method for creating twin light beams, researchers at the Joint Quantum Institute (JQI) of the Commerce Department's National Institute of Standards and Technology (NIST) and the University of Maryland have produced "quantum images," pairs of information-rich visual patterns whose features are "entangled," or inextricably linked by the laws of quantum physics.
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| ©Vincent Boyer/JQI |
| In this photo montage of actual quantum images, two laser beams coming from the bright glare in the distance transmit images of a cat-like face at two slightly different frequencies (represented by the orange and the purple colors). The twisted lines indicate that the seemingly random changes or fluctuations that occur over time in any part of the orange image are strongly interconnected or "entangled" with the fluctuations of the corresponding part in the purple image. Though false color has been added to the cats' faces, they are otherwise actual images obtained in the experiment. |
BOZEMAN -- The sun has been laying low for the past couple of years, producing no sunspots and giving a break to satellites.
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| ©NASA |
| Periods of inactivity are normal for the sun, but this period has gone on longer than usual. |
Flying saucers may soon be more fact than mere science fiction. University of Florida mechanical and aerospace engineering associate professor Subrata Roy has submitted a patent application for a circular, spinning aircraft design reminiscent of the spaceships seen in countless Hollywood films. Roy, however, calls his design a "wingless electromagnetic air vehicle," or WEAV.
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| ©University of Florida |
| Cut-away illustration of proposed prototype mini-flying saucer. |
IP address is not enough proof, they say
U.S. House members who say that China may have been responsible for attacks on their computers have provided little evidence to back up their claims, according to computer security experts.
The two Republican congressmen, Reps. Frank Wolf of Virginia and Christopher Smith of New Jersey,disclosed Wednesday that computers in their offices were hacked in late 2006 and early 2007. Both men have been critical of China's human rights record and said that the attacks raised concerns that they were being targeted for their support of Chinese dissidents.
U.S. House members who say that China may have been responsible for attacks on their computers have provided little evidence to back up their claims, according to computer security experts.
The two Republican congressmen, Reps. Frank Wolf of Virginia and Christopher Smith of New Jersey,disclosed Wednesday that computers in their offices were hacked in late 2006 and early 2007. Both men have been critical of China's human rights record and said that the attacks raised concerns that they were being targeted for their support of Chinese dissidents.
HOUSTON - NASA engineers were trying to identify an object that floated away from Discovery and were analyzing a protrusion found on its rudder Friday, a day before the space shuttle was scheduled to land.
The two issues were noticed after a routine test of the spacecraft's flight control systems and steering jets.
The two issues were noticed after a routine test of the spacecraft's flight control systems and steering jets.
From paintings and photographs to coins and credit cards, we are constantly surrounded by symbolic artefacts. The mental representation of symbols -- objects that arbitrarily represent other objects -- ultimately affords the development of language, and certainly played a decisive role in the evolution of our hominid ancestors. Can other animal species also comprehend and use symbols? Some evidence suggests that apes, our closest relatives, can indeed use symbols in various contexts. However, little is known about the symbolic competence of phylogenetically more distant species.
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| ©Elisabetta Visalberghi |
| Capuchin monkey (Cebus paella) |
HOUSTON -- NASA researchers and scientists from the United States, Germany and Japan have found a new mineral in material that likely came from a comet.
The mineral, a manganese silicide named Brownleeite, was discovered within an interplanetary dust particle, or IDP, that appears to have originated from comet 26P/Grigg-Skjellerup. The comet originally was discovered in 1902 and reappears every 5 years. The team that made the discovery is headed by Keiko Nakamura-Messenger, a space scientist at NASA's Johnson Space Center in Houston.
"When I saw this mineral for the first time, I immediately knew this was something no one had seen before," said Nakamura-Messenger. "But it took several more months to obtain conclusive data because these mineral grains were only 1/10,000 of an inch in size."
The mineral, a manganese silicide named Brownleeite, was discovered within an interplanetary dust particle, or IDP, that appears to have originated from comet 26P/Grigg-Skjellerup. The comet originally was discovered in 1902 and reappears every 5 years. The team that made the discovery is headed by Keiko Nakamura-Messenger, a space scientist at NASA's Johnson Space Center in Houston.
"When I saw this mineral for the first time, I immediately knew this was something no one had seen before," said Nakamura-Messenger. "But it took several more months to obtain conclusive data because these mineral grains were only 1/10,000 of an inch in size."
Serious comet chasers have been watching Comet C/2007 W1 (Boattini) for some time. For awhile, it exceeded its predicted brightness but is back to cruising at normal. During the time this photograph was taken, Boattini was a southern hemisphere object... But not for long. Now its about to round the Sun and head north!
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| ©Unknown |
| Comet Boattini |
MIT researchers have figured out how bacteria ensure that they respond correctly to hundreds of incoming signals from their environment.
The researchers also successfully rewired the cellular communications pathways that control those responses, raising the possibility of engineering bacteria that can serve as biosensors to detect chemical pollutants. The work is reported in the June 13 issue of Cell.
Led by MIT biology professor Michael Laub, the team studied genomes of nearly 200 bacteria, which can have hundreds of different pathways that respond to different types of external stimuli. Nutrients, antibiotics, temperature or light can evoke a variety of responses, including transcription of particular genes.
In most cases, the pathways involve two proteins. The first protein, an enzyme known as a histidine kinase, receives the external signal and then activates the second protein, known as a response regulator.
The researchers also successfully rewired the cellular communications pathways that control those responses, raising the possibility of engineering bacteria that can serve as biosensors to detect chemical pollutants. The work is reported in the June 13 issue of Cell.
Led by MIT biology professor Michael Laub, the team studied genomes of nearly 200 bacteria, which can have hundreds of different pathways that respond to different types of external stimuli. Nutrients, antibiotics, temperature or light can evoke a variety of responses, including transcription of particular genes.
In most cases, the pathways involve two proteins. The first protein, an enzyme known as a histidine kinase, receives the external signal and then activates the second protein, known as a response regulator.
