A new study could explain why DNA and not RNA, its older chemical cousin, is the main repository of genetic information. The DNA double helix is a more forgiving molecule that can contort itself into different shapes to absorb chemical damage to the basic building blocks -- A, G, C and T -- of genetic code. In contrast, when RNA is in the form of a double helix it is so rigid and unyielding that rather than accommodating damaged bases, it falls apart completely.
The jaws of trap-jaw ants can generate forces hundreds of times their body weight and snap shut at speeds reaching 145 miles per hour -- over 2,000 times faster than the blink of an eye.
It takes a well-trained eye to spot an irregular heartbeat in the peaks and valleys of an electrocardiogram. The same goes for identifying an extinct ape from a single fossilized tooth, or telling an original van Gogh from a fake.
But in recent years, applied mathematician Ingrid Daubechies has been training computers to churn through ECG tracings, high-resolution scans of fossils, paintings and other complex digital data and work things out automatically.
DURHAM, N.C. – A legacy of acid rain has acidified forest soils throughout the northeastern United States, lowering the growth rate of trees. In an attempt to mitigate this trend, in 1999 scientists added calcium to an experimental forest in New Hampshire; tree growth recovered, but a decade later there was a major increase in the nitrogen content of stream water draining the site.
The green ring of cells lining this fruit fly’s digestive tract normally lie dormant, but after injury they spring into action, growing and copying their DNA to help the fly’s gut heal. To repair damage, organs either make new cells to replace those that were lost, or enlarge the cells that remain.
Researchers from Duke University and UNC-Chapel Hill are testing the ability of drones to detect sharks in coastal waterways.
In a collaborative study funded by North Carolina Aquariums, the researchers are examining whether drones can effectively pinpoint bonnethead sharks in different habitats and water conditions.
Biomedical Engineer Amanda Randles is building models to simulate how individual blood cells travel throughout the human body. But running these simulations is no small feat; even powerful supercomputers struggle to calculate fluid flows that include pulsing heartbeats, webs of blood vessels, and trillions of cells. To speed up the simulations, Randles’ algorithms divide each vessel into smaller regions, and calculate the blood flow in each region separately.
When I enter my lab, I’m greeted by the pops and crackles of mantis shrimp smashing snail shells with tiny hammers moving at bullet-like accelerations. Other days, I listen to their eerie, low-frequency rumbles, joined by the scratchy rasps of the violin- like mechanism that spiny lobsters use to scare away predators. For the past twenty years, I have probed the physics and evolution of these and other strange and wonderful creatures. Many have revealed unexpected insights into extraordinary capabilities that are unmatched by human- made systems.
DURHAM, N.C. -- Allowing underwater seismic surveys for oil and gas to be conducted off the U.S. Mid-Atlantic and Southeast coasts could pose a substantial threat to one of the world’s most critically endangered whale species, a group of leading marine scientists say.
Scientists can now watch how hundreds of individual cells work together to maintain and regenerate skin tissue, thanks to a genetically engineered line of technicolor zebrafish.
Every cell on the surface of the fish, from the center of the eye to the tip of each scale, is genetically programmed to glow with a slightly different hue. But these zebrafish weren’t bred to brighten up an aquarium; the colors effectively stamp each cell with a permanent barcode, letting scientists track its movements in a live animal for days or even weeks at a time.