Science & Technology
The tsunami washed over Fire Island and, to the west, waves perhaps as high as 20 feet spilled into Lower Manhattan. The furious onrush of water left sediment a foot and a half deep on the Jersey Shore, and debris cascaded far up the Hudson River.
© Rockefeller University
Seeing through walls. An experiment shows that when dividing strep bacteria are stripped of their surface proteins (left), they begin to grow back in just minutes. One surface protein, protein M (green), anchors to the spot where sortase A (red) assembles. Before the bacteria finish dividing (right), sortase A has already begun to migrate to the new site of division.
Seeing through walls. An experiment shows that when dividing strep bacteria are stripped of their surface proteins (left), they begin to grow back in just minutes. One surface protein, protein M (green), anchors to the spot where sortase A (red) assembles. Before the bacteria finish dividing (right), sortase A has already begun to migrate to the new site of division.
The work, led by Vincent A. Fischetti, head of the Laboratory of Bacterial Pathogenesis and Immunology, provides, for the first time ever, a look inside the rapidly multiplying and highly contagious Streptococcus pyogenes, the culprit behind a myriad of diseases, including strep throat and rheumatic fever. At a time when organisms are increasingly acquiring "superbug" powers, Fischetti and his colleague Assaf Raz, a graduate student in the lab, have used the technique to look specifically at a well-known enzyme called sortase A and its distribution inside the cell. Common to all gram-positive bacteria, the enzyme functions by anchoring surface proteins to the cell wall, endowing the bacteria with their infectious properties.
© M. Troyer
Perfect helium crystals are normal classical crystals in which the atoms are localised at their lattice positions. At the point of a crystal defect, such as the grain boundary shown in the image, quantum mechanical effects cause the atoms to lose their exact position. They become delocalized and can flow along the defect without any friction: a "supersolid" is formed, a solid that is also a perfect liquid at the same time.
Perfect helium crystals are normal classical crystals in which the atoms are localised at their lattice positions. At the point of a crystal defect, such as the grain boundary shown in the image, quantum mechanical effects cause the atoms to lose their exact position. They become delocalized and can flow along the defect without any friction: a "supersolid" is formed, a solid that is also a perfect liquid at the same time.
Matthias Troyer and his team carry out experiments at their computers. Troyer is Professor of Computational Physics at ETH Zurich's Institute of Theoretical Physics. He simulates quantum phenomena such as "supersolid" structures. Supersolidity describes a physical phase which can occur at very low temperatures and where a material appears to be solid and "superfluid" at the same time.
Enquiries from the armed forces
However, the word can be misunderstood, as was discovered by one of Troyer's colleagues who works on the phenomenon in the USA. The US Navy thought that "supersolid" meant "extremely hard" and so asked the physicist whether such a material could be used to armour ships or at least put into a spray can or be used to kill someone. The physicist answered "No" - because "supersolid" does not mean super-hard. After that, the army showed no further interest.
SEC. 321. GEORGE E. BROWN, JR. NEAR-EARTH OBJECT SURVEY.
(a) Short Title- This section may be cited as the 'George E. Brown, Jr. Near-Earth Object Survey Act'.
(b) Findings- The Congress makes the following findings:
(a) Short Title- This section may be cited as the 'George E. Brown, Jr. Near-Earth Object Survey Act'.
(b) Findings- The Congress makes the following findings:
(1) Near-Earth objects pose a serious and credible threat to humankind, as many scientists believe that a major asteroid or comet was responsible for the mass extinction of the majority of the Earth's species, including the dinosaurs, nearly 65,000,000 years ago.
(2) Similar objects have struck the Earth or passed through the Earth's atmosphere several times in the Earth's history and pose a similar threat in the future.
(3) Several such near-Earth objects have only been discovered within days of the objects' closest approach to Earth, and recent discoveries of such large objects indicate that many large near-Earth objects remain undiscovered.
(4) The efforts taken to date by NASA for detecting and characterizing the hazards of near-Earth objects are not sufficient to fully determine the threat posed by such objects to cause widespread destruction and loss of life.
It is science's star experiment: an attempt to create an artificial sun on earth - and provide an answer to the world's impending energy shortage.
While it has seemed an impossible goal for nearly 100 years, scientists now believe that they are on brink of cracking one of the biggest problems in physics by harnessing the power of nuclear fusion, the reaction that burns at the heart of the sun.
In the spring, a team will begin attempts to ignite a tiny man-made star inside a laboratory and trigger a thermonuclear reaction.
Its goal is to generate temperatures of more than 100 million degrees Celsius and pressures billions of times higher than those found anywhere else on earth, from a speck of fuel little bigger than a pinhead. If successful, the experiment will mark the first step towards building a practical nuclear fusion power station and a source of almost limitless energy.
While it has seemed an impossible goal for nearly 100 years, scientists now believe that they are on brink of cracking one of the biggest problems in physics by harnessing the power of nuclear fusion, the reaction that burns at the heart of the sun.
In the spring, a team will begin attempts to ignite a tiny man-made star inside a laboratory and trigger a thermonuclear reaction.
Its goal is to generate temperatures of more than 100 million degrees Celsius and pressures billions of times higher than those found anywhere else on earth, from a speck of fuel little bigger than a pinhead. If successful, the experiment will mark the first step towards building a practical nuclear fusion power station and a source of almost limitless energy.
© University of Toronto
The top surface of the columns in the Giant's Causeway, Northern Ireland.
The top surface of the columns in the Giant's Causeway, Northern Ireland.
"The size of the columns, which varies from site to site between a few inches and a few yards, is primarily determined by the speed at which lava from a volcanic eruption cools," says U of T physics professor Stephen Morris, who supervised the thesis project of PhD student Lucas Goehring. Cooling lava sometimes forms strange column-shaped formations with a remarkable degree of order. The most famous of these hexagonal columns are found at the Giant's Causeway in Northern Ireland, where they are said to be the work of Finn MacCool, an Irish giant.
© NASA/Jet Propulsion Laboratory
Is dark energy really real? Is our universe really accelerating? These questions hang around in the mind of Ali Vanderveld, a post-doctoral cosmologist at JPL.
Is dark energy really real? Is our universe really accelerating? These questions hang around in the mind of Ali Vanderveld, a post-doctoral cosmologist at JPL.
But is dark energy really real? Is our universe really accelerating? These questions hang around in the mind of Ali Vanderveld, a post-doctoral cosmologist at JPL. Vanderveld and her colleagues recently published a paper in the journal Physical Review looking at how giant holes in our "Swiss-cheese-like" universe might make space look as if it's accelerating when it's really not. They concluded these holes, or voids, are not sufficient to explain away dark energy; nevertheless, Vanderveld says it's important to continue to question fundamental traits of the very space we live in.
"Sometimes we take dark energy for granted," said Vanderveld. "But there are other theories that could explain why the universe appears to be moving apart at faster and faster speeds."
From a possible cure for Aids to a new discovery of quasiparticles, 2008 brought with it important scientific and medical advances as well as great disappointments such as the unexpected malfunction of the Large Hadron Collider, which postponed the multi billion dollar scientific enterprise by several months.
Continuing our annual tradition since 2006, TFOT presents a summary of the passing year's most remarkable discoveries, innovations, research, and applications in science, medicine, and space.
Continuing our annual tradition since 2006, TFOT presents a summary of the passing year's most remarkable discoveries, innovations, research, and applications in science, medicine, and space.
© Douglas Hofmann/Caltech
Samples of the new titanium-based metallic-glass composites show their toughness and ductility.
Samples of the new titanium-based metallic-glass composites show their toughness and ductility.
Earlier this year, the same Caltech group had published a paper in the journal Nature, describing new strategies for creating the liquid-metal composites. This research resulted in "alloys with unrivaled strength and toughness," notes Douglas Hofmann, visiting scientist and lead author on the PNAS paper that, along with the Nature paper, describes work he did while a graduate student at Caltech. "They are among the toughest engineering materials that currently exist."
© John Serences, UC San Diego
Led by John Serences, assistant professor of psychology and head of the Perception and Cognition Lab at UC San Diego, the study is published in the Dec. 26 issue of the Cell Press journal Neuron.
Past rewards influence how humans (and other animals) make decisions. We've known about that for a long time, said Serences - through day-to-day experience as well as the numerous experiments of economists and cognitive psychologists. Though more and more research is looking into it, little is known about how rewards affect the way the brain processes incoming sensory information, specifically as it relates to vision. Could it be that we see things differently if they have paid off before?
