Science & Technology


US biologists shed light on how deadly virus becomes infectious

CHICAGO - Biologists have mapped how a deadly class of viruses including dengue, West Nile, yellow fever and encephalitis become infectious in a pair of studies published in the journal Science.

"This is possibly the most detailed understanding of how any virus matures," said study author Michael Rossmann of Purdue University in Indiana.


Climate Threat: Thawing Tundra Releases Infected Corpses

Yards and yards of clear plastic sheeting line the cellar floor, dwarfing the corpse: headless, frail, supine. The young bony arms - covered in fine black powder from centuries of immobility in the frozen tundra - are crossed at rest, reminiscent of a ceremonial burial. Camera flashes illuminate the scene. Several dozen scientists stand around the body, murmuring in Russian and English about the find of the day.

How long do you think it was buried? Do you think it's male or female? How did they get it back to camp? And the pervasive thought: I don't think we should touch it. He could have died of smallpox.


Astronomers Coordinating International Observatories In White-dwarf Watch

Judi Provencal is star-struck, but not so much by the glitz and glam of Hollywood. You have to look heavenward through a telescope to see the object of her fascination--to pale stars called white dwarfs, their brilliance faded because all of their nuclear fuel has been burned up.

A white dwarf is a star that is "dying," cooling down in the twilight of its life. It's what the sun will become in about 4 billion years, according to Provencal.

white dwarf
©University of Delaware
A white dwarf is in the center of planetary nebula NGC6751. Near the ring of gas is a foreground star.


Exquisite Photon Control On A Silicon Chip Is Major Advance Toward Quantum Computing

A team of physicists and engineers has demonstrated exquisite control of single particles of light -- photons -- on a silicon chip to make a major advance towards the long sought after goal of a super-powerful quantum computer.

single photons
©Carmel King
Generating and detecting single photons.

The team's chips, fabricated at CIP Technologies, have dimensions measured in millimetres.

This impressive miniaturisation was permitted thanks to the silica-on-silicon technology used in commercial devices for modern optical telecommunications, which guides light on a chip in the same way as in optical fibres.


Biosensing Nanodevice To Revolutionize Health Screenings

One day soon a biosensing nanodevice developed by Arizona State University researcher Wayne Frasch may eliminate long lines at airport security checkpoints and revolutionize health screenings for diseases like anthrax, cancer and antibiotic resistant Staphylococcus aureus (MRSA).

Even more incredible than the device itself, is that it is based on the world's tiniest rotary motor: a biological engine measured on the order of molecules.

©Wayne Frasch and David Spetzler
Composition of the nanodevice.


Epilepsy Marked By Neural 'Hub' Network

An increased number of neuron "hubs" in the epileptic brain may be the root cause for the seizures that characterize the disorder, according to a UC Irvine study.

Researchers Robert Morgan and Ivan Soltesz with the Department of Anatomy and Neurobiology identified that these hubs - a small number of highly connected neurons - are formed in the hippocampus during the transition from a healthy brain to an epileptic one. The increased number of connections among these hubs, they found, circulate and amplify signals to such a degree that they overwhelm brain networks, leading to epileptic seizures.

Neural hub
©University of California - Irvine
Neural hub figure.


Organic Molecule, Amino Acid-Like, Found In Constellation Sagittarius

Researchers from the Max Planck Institute for Radio Astronomy (MPIfR) in Bonn have detected for the first time a molecule closely related to an amino acid: amino acetonitrile. The organic molecule was found with a 30 metre radio telescope in Spain and two radio interferometers in France and Australia in the "Large Molecule Heimat", a giant gas cloud near the galactic centre in the constellation Sagittarius (Astronomy & Astrophysics, in press).

Amino acetonitrile
©Sven Thorwirth, MPIfR
Amino acetonitrile.


Planet in Progress? Evidence Of A Huge Planet Forming In Star System

Astrophysicists have a new window into the formation of planets. Ben R. Oppenheimer, Assistant Curator in the Department of Astrophysics at the American Museum of Natural History, and colleagues have imaged a structure within the disk of material coalescing from the gas and dust cloud surrounding a well-studied star, AB Aurigae.

star AB Aurigae
©American Museum Of Natural History
Coronagraphic image of the polarized light around the star AB Aurigae, showing the distribution of dust in the inner part of a complex disk of material around this star. The shaded middle region is covered to block out light from the star. The inset at upper right is a blow-up of the depleted region of dust to the NNW of the star.

Within that structure, it appears that an object is forming, either a small body currently accreting dust or a brown dwarf (a body intermediate between stars and planets) between 5 and 37 times the mass of Jupiter. The observations, accepted for publication in the Astrophysical Journal, represent a significant step toward direct imaging and study of exoplanets (planets orbiting stars other than the Sun), and may bear on theories of planet and brown dwarf formation.


World's First Movie Of Black Hole Birth

The date of March 19, 2008 marked the brightest ever cosmic explosion observed from the Earth. The outburst known as GRB 080319B was probably the death of a massive star leading to the creation of a black hole. For the first time the birth of a black hole has been filmed.

Cameras of the "Pi of the Sky" project recorded this remarkable event with a 4-minute sequence of 10-second-long images. In almost 20 seconds the object became so bright that it could be visible with the naked eye. Then it began fading and in 4 minutes it became 100 times fainter. At that time the observation was taken over by larger telescopes.

black hole birth
©Soltan Institute for Nuclear Studies
2008.03.19 "Pi of the Sky" telescope detected the brightest ever optical outburst from a distant universe. The explosion happened 7.5 billion light years from the Earth, halfway across the visible Universe. The telescope is only 71 mm in diameter.


Key factor in brain development revealed, offers insight into disorder

In the earliest days of brain development, the brain's first cells - neuroepithelial stem cells -- divide continuously, producing a population of cells that eventually evolves into the various cells of the fully formed brain. Now, scientists have identified a gene that, in mice, is critical for these stem cells to divide correctly. Without it, they fail to divide, and die.

The finding offers insight into the first steps of brain development, and may shed light, the scientists say, on a rare pediatric disorder known as lissencephaly, or "smooth brain" disease.