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Sunday, February 17, 2008

How Snakes Hear

It is often believed that snakes cannot hear. This presumption is fed by the fact that snakes lack an outer ear and that scientific evidence of snakes responding to sound is scarce. Snakes do, however, possess an inner ear with a functional cochlea.


Batman and Copperhead © DC Comics
Now scientists have evidence that snakes use this structure to detect minute vibrations of the sand surface that are caused by prey moving. Their ears are sensitive enough to not only “hear” the prey approaching, but also to allow the brain to localize the direction it is coming from.

Any disturbance at a sandy surface leads to vibration waves that radiate away from the source along the surface. A snake can detect these small ripples and if it rests its head on the ground, the two sides of the lower jaw are brought into vibration by the incoming wave. These vibrations are then transmitted directly into the inner ear by means of a chain of bones attached to the lower jaw. This process is comparable to the transmission of auditory signals by the ossicles in the human middle ear. The snake thus literally hears surface vibrations.

The extraordinary flexibility of the lower jaw of snakes has evolved because being able to swallow very large meals is a big advantage if food is in short supply and competition fierce. Moreover, the separation of the sides of the lower jaw also allowed this very interesting form of hearing to develop. press release

Auditory Localization of Ground-Borne Vibrations in Snakes. 2008. P. Friedel et al. Physical Review Letters, 100, 048701.

Friday, February 15, 2008

Galaxy NGC 11312: Cosmic Fossil

The NASA/ESA Hubble Space Telescope has captured a new image of the galaxy NGC 1132 which is, most likely, a cosmic fossil – the aftermath of an enormous multi-galactic pile-up, where the carnage of collision after collision has built up a brilliant but fuzzy giant elliptical galaxy far outshining typical galaxies.

Image:NASA, ESA and the Hubble Heritage (STScI/AURA)-ESA/Hubble Collaboration.
The elliptical galaxy NGC 1132, seen in this latest image from Hubble, belongs to a category of galaxies called giant ellipticals. NGC 1132, together with the small dwarf galaxies surrounding it, are dubbed a “fossil group” as they are most likely the remains of a group of galaxies that merged together in the recent past.

The origin of fossil group systems remains a puzzle. The most likely explanation is that they are the end-products of a cosmic feeding frenzy in which a large cannibal galaxy devours all of its neighbours. A less likely explanation is that they may be very rare objects that formed in a region or period of time where the growth of moderate-sized galaxies was somehow suppressed, and only one large galaxy formed.

Many galaxies reside in groups that are gravitationally bound together, including our own Milky Way, which is part of the Local Group. Sometimes gravity makes galaxies collide and eventually merge into one single galaxy. There is strong evidence that the Milky Way is one such cannibal that has snacked on numerous smaller galaxies during its lifetime, inheriting their stars in the process. Scientists are keenly studying the environment surrounding galaxies such as NGC 1132 using space telescopes like Hubble, and they try to trace the history of the formation these galaxies by analysing their properties.


NGC 1132 is located approximately 320 million light-years away in the constellation of Eridanus, the River. press release

Thursday, February 7, 2008

Mummy Lice Migrate Arounrd The World

Lice from 1,000-year-old mummies in Peru may unravel important clues about a different sort of passage: the migration patterns of America’s earliest humans.


DNA sequencing found the strain of lice to be genetically the same as the form of body lice that spawns several deadly diseases, including typhus, which was blamed for the loss of Napoleon’s grand army and millions of other soldiers, he said.

The discovery of these parasites on 11th-century Peruvian mummies proves they were infesting the native Americans nearly 500 years before Europeans arrived, Reed said.


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“This definitely goes against the grain of conventional thought that all diseases were transmitted from the Old World to the New World at the time of Columbus,” he said.


It came as a surprise to Reed and his research team that the type of lice on the mummies was of the same genetic type as those found as far away as the highlands of Papua, New Guinea, instead of the form of head lice that is widespread in the Western Hemisphere, Reed said. This latter version, the bane of many school children, accounts for more than half the cases of lice that appear in the United States, Canada and Central America, he said. ” link

Molecular Identification of Lice from Pre‐Columbian Mummies. 2008. Didier Raoult et al. Journal of Infectious Diseases electronically published 6 February 2008.

Saturday, February 2, 2008

Quantum Teleportation and Memory in Tandem Achieved


Brainiac 5 & Superman © DC Comics
In research that may be a key step toward real-life quantum communication—the transmission of information using atoms, photons, or other quantum objects—researchers created an experiment in which a quantum bit of information is transported across a distance of seven meters and briefly stored in memory. This is the first time that both quantum memory and teleportation, as the information transfer is known, have been demonstrated in a single experiment.

In the present research an unknown quantum state of a photonic qubit is transferred into quantum memory via teleportation and is stored by two clusters of rubidium atoms. Each cluster contains approximately one million atoms, collected by a magneto-optical trap. The teleported photonic qubit can be stored in memory and read out up to eight microseconds (millionths of a second) before the state is lost.

This setup does have some serious problems. The quantum memory duration is very short and the probability that the photon will be teleported is low. Therefore, the researchers say that “significant improvements” need to be made before the scheme could be used in practical applications. link

Memory-built-in quantum teleportation with photonic and atomic qubits. 2008. Yu-Ao Chen, et al. Nature Physics advance online publication, 20 January 2008.

The top-left diagram shows the structure and the initial populations of atomic levels for the two ensembles. At Bob's site, the anti-Stokes fields emitted from U and D are collected and combined at PBS1, selecting perpendicular polarizations. Then the photon travels 7 m through the fibres to Alice's site to overlap with the initial unknown photon on a beam splitter (BS) to carry out the BSM. The results of the BSM are sent to Bob through a classical channel. Bob then carries out the verification of the teleported state in the U and D ensembles by converting the atomic excitation to a photonic state. If the state | + is registered, Bob directly carries out a polarization analysis on the converted photon to measure the teleportation fidelity. On the other hand, if the state | - is detected, the converted photon is sent through a half-wave plate via the first-order diffraction of an AOM (not shown). The half-wave plate is set at 0° serving as the unitary transformation of . Then the photon is sent through the polarization analyser to obtain the teleportation fidelity.

Friday, February 1, 2008

NASA to Beam Beatles' 'Across the Universe' Into Space

For the first time ever, NASA will beam a song -- The Beatles' "Across the Universe" -- directly into deep space at 7 p.m. EST on Feb. 4.



The transmission over NASA's Deep Space Network will commemorate the 40th anniversary of the day The Beatles recorded the song, as well as the 50th anniversary of NASA's founding and the group's beginnings. Two other anniversaries also are being honored: The launch 50 years ago this week of Explorer 1, the first U.S. satellite, and the founding 45 years ago of the Deep Space Network, an international network of antennas that supports missions to explore the universe.

The transmission is being aimed at the North Star, Polaris, which is located 431 light years away from Earth. The song will travel across the universe at a speed of 186,000 miles per second. Former Beatle Sir Paul McCartney expressed excitement that the tune, which was principally written by fellow Beatle John Lennon, was being beamed into the cosmos.

"Amazing! Well done, NASA!" McCartney said in a message to the space agency. "Send my love to the aliens. All the best, Paul." link

Thursday, January 31, 2008

Finding the Door to a Parallel Universe

If there were a portal linking us to a parallel universe or some other region of space, how would we spot it? One suggestion is that it will give itself away by the curious way it bends light.
The existence of wormholes linking different regions of space was suggested in 1916 by the Austrian physicist Ludwig Flamm as a possible solution to equations of general relativity, which Einstein had published that year. They have since become accepted as a natural consequence of general relativity, which predicts that matter entering one end of a wormhole would instantly emerge somewhere else, so long as the wormhole is somehow propped open.


Though no direct evidence for wormholes has been observed, this could be because they are disguised as black holes. Now Alexander Shatskiy of the Lebedev Physical Institute in Moscow, Russia, is suggesting a possible way to tell the two kinds of object apart. His idea assumes the existence of a bizarre substance called “phantom matter”, which has been proposed to explain how wormholes might stay open. Phantom matter has negative energy and negative mass, so it creates a repulsive effect that prevents the wormhole closing.

According to Shatskiy’s calculations, the way phantom matter deflects light would give the wormhole a signature that astronomers could look out for. The gravity of an object with a positive mass, such as an ordinary black hole, focuses light rays passing close to it as if it were a giant concave lens – an effect known as gravitational lensing. Phantom matter’s negative mass would have the opposite gravitational lensing effect to normal matter, making any light passing through the wormhole from another universe or point in space-time diverge, and emerge from it as a bright ring. Meanwhile, any stars behind it would shine through the middle. Shatskiy suggests that his idea might offer a way for future space-based observatories such as Russia’s planned Millimetron Project to look for wormholes at the centre of large galaxies.

Thursday, January 17, 2008

Krupp Artist Self-Portrait Buttons


Some of the goodies that Denis Kitchen was selling 30+ years ago!




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